Shape

Is the abdomen of normal contour and fullness, or distended? Is it scaphoid (sunken)?

A scaphoid abdomen is seen in advanced stages of starvation and malignant disease.

The umbilicus

Normally the umbilicus is slightly retracted and inverted. If it is everted, then an umbilical hernia may be present and this can be confirmed by feeling an expansile impulse on palpation of the swelling when the patient coughs. The hernial sac may contain omentum, bowel or fluid. A common finding in the umbilicus of elderly obese people is a concentration of inspissated desquamated epithelium and other debris (omphalolith).

Movements of the abdominal wall

Normally there is a gentle rise in the abdominal wall during inspiration and a fall during expiration; the movement should be free and equal on both sides. In generalized peritonitis, this movement is absent or markedly diminished (the ‘still, silent abdomen’). To aid the recognition of intra-abdominal movements, shine a light across the patient’s abdomen. Even small movements of the intestine may then be detected by alterations in the pattern of shadows cast over the abdomen.

Visible pulsation of the abdominal aorta may be noticed in the epigastrium and is a frequent finding in nervous, thin patients. It must be distinguished from an aneurysm of the abdominal aorta, where pulsation is more obvious and a widened aorta is felt on palpation.

Visible peristalsis of the stomach or small intestine may be observed in three situations:

Skin and surface of the abdomen

In marked abdominal distension, the skin is smooth and shiny. Striae atrophica or gravidarum are white or pink wrinkled linear marks on the abdominal skin. They are produced by gross stretching of the skin with rupture of the elastic fibres and indicate a recent change in size of the abdomen, such as is found in pregnancy, ascites, wasting diseases and severe dieting. Wide purple striae are characteristic of Cushing’s syndrome and excessive steroid treatment.

Note any scars present, their site, whether they are old (white) or recent (red or pink), linear or stretched (and therefore likely to be weak and contain an incisional hernia). Common examples are given in Fig. 12.7.

Figure 12.7 Some commonly used abdominal incisions. The midline and oblique incisions avoid damage to the innervation of the abdominal musculature and the later development of incisional hernia.

Look for prominent superficial veins, which may be apparent in three situations (Fig. 12.8): thin veins over the costal margin, usually of no significance; occlusion of the inferior vena cava; and venous anastomoses in portal hypertension. Inferior vena caval obstruction not only causes oedema of the limbs, buttocks and groins but, in time, distended veins on the abdominal wall and chest wall appear. These represent dilated anastomotic channels between the superficial epigastric and circumflex iliac veins below, and the lateral thoracic veins above, conveying the diverted blood from the long saphenous vein to the axillary vein; the direction of flow is therefore upwards. If the veins are prominent enough, try to detect the direction in which the blood is flowing by occluding a vein, emptying it by massage and then looking for the direction of refill. Distended veins around the umbilicus (caput medusae) are uncommon but signify portal hypertension, other signs of which may include splenomegaly and ascites. These distended veins represent the opening up of anastomoses between portal and systemic veins and occur in other sites, such as oesophageal and rectal varices.

Figure 12.8 Prominent veins of the abdominal wall.

Pigmentation of the abdominal wall may be seen in the midline below the umbilicus, where it forms the linea nigra and is a sign of pregnancy. Erythema ab igne is a brown mottled pigmentation produced by constant application of heat, usually a hot water bottle or heat pad, on the skin of the abdominal wall. It is a sign that the patient is experiencing severe ongoing pain such as from chronic pancreatitis.

Finally, uncover and inspect both groins, and the penis and scrotum of a male, for any swellings and to ensure that both testes are in their normal position. Then bring the sheet back up to the level of the symphysis pubis.

Left kidney

The right hand is placed anteriorly in the left lumbar region while the left hand is placed posteriorly in the left loin (Fig. 12.12). Ask the patient to take a deep breath in, press the left hand forward and the right hand backward, upward and inward. The left kidney is not usually palpable unless either low in position or enlarged. Its lower pole, when palpable, is felt as a rounded firm swelling between both right and left hands (i.e. bimanually palpable) and it can be pushed from one hand to the other, in an action which is called ‘ballotting’.

Figure 12.12 Palpation of the left kidney.

Spleen

Like the left kidney, the spleen is not normally palpable. It has to be enlarged to two or three times its usual size before it becomes palpable, and then is felt beneath the left subcostal margin. Enlargement takes place in a superior and posterior direction before it becomes palpable subcostally. Once the spleen has become palpable, the direction of further enlargement is downwards and towards the right iliac fossa (Fig. 12.13). Place the flat of the left hand over the lower-most rib cage posterolaterally, thus restricting the expansion of the left lower ribs on inspiration and concentrating more of the inspiratory movement into moving the spleeen downwards. The right hand is placed beneath the costal margin well out to the left. Press in deeply with the fingers of the right hand beneath the costal margin, at the same time exerting considerable pressure medially and downwards with the left hand (Fig. 12.14), and then ask the patient to breathe in deeply. Repeat this manoeuvre with the right hand being moved more medially beneath the costal margin on each occasion (Fig. 12.15). If enlargement of the spleen is suspected from the history and it is still not palpable, turn the patient half on to the right side, ask him to relax back onto your left hand, which is now supporting the lower ribs, and repeat the examination as above. Alternatively the spleen may be very large and the lower edge may be much lower than at first suspected. It may help to ask the patient to place the left hand on your right shoulder while palpating for the spleen.

Figure 12.13 The direction of enlargement of the spleen. The spleen has a characteristic notched shape and the organ moves downwards during full inspiration.

Figure 12.14 Palpation of the spleen. Start well out to the left.

Figure 12.15 Palpation of the spleen more medially than in Figure 12.14.

In minor degrees of enlargement, the spleen will be felt as a firm swelling with smooth, rounded borders. Where considerable splenomegaly is present, its typical characteristics include a firm swelling appearing beneath the left subcostal margin in the left upper quadrant of the abdomen, which is dull to percussion, moves downwards on inspiration, is not bimanually palpable, whose upper border cannot be felt (i.e. one cannot ‘get above it’) and in which a notch can often, though not invariably, be felt in the lower medial border. The last three features distinguish the enlarged spleen from an enlarged kidney; in addition, there is usually a band of colonic resonance anterior to an enlarged kidney.

Right kidney

Feel for the right kidney in much the same way as for the left. Place the right hand horizontally in the right lumbar region anteriorly with the left hand placed posteriorly in the right loin. Push forwards with the left hand, press the right hand inward and upward (Fig. 12.16) and ask the patient to take a deep breath in. The lower pole of the right kidney, unlike the left, is commonly palpable in thin patients and is felt as a smooth, rounded swelling which descends on inspiration and is bimanually palpable and may be ‘ballotted’.

Figure 12.16 Palpation of the right kidney.

Liver

Sit on the couch beside the patient. Place both hands side-by-side flat on the abdomen in the right subcostal region lateral to the rectus with the fingers pointing towards the ribs. If resistance is encountered, move the hands further down until this resistance disappears. Exert gentle pressure and ask the patient to breathe in deeply. Concentrate on whether the edge of the liver can be felt moving downwards and under the examining hand (Fig. 12.17).

Figure 12.17 Palpation of the liver: preferred method.

Repeat this manoeuvre working from lateral to medial regions to trace the liver edge as it passes upwards to cross from right hypochondrium to epigastrium. Another commonly employed though less accurate method of feeling for an enlarged liver is to place the right hand below and parallel to the right subcostal margin. The liver edge will then be felt against the radial border of the index finger (Fig. 12.18). The liver is often palpable in normal patients without being enlarged. The lower edge of the liver can be clarified by percussion (see below), as can the upper border in order to determine overall size: a palpable liver edge can be due to enlargement, or displacement downwards by lung pathology. Hepatomegaly conventionally is measured in centimetres palpable below the right costal margin, which should be determined with a ruler if possible.

Figure 12.18 Palpation of the liver: alternative method.

Try to make out the character of its surface (i.e. whether it is soft, smooth and tender as in heart failure, very firm and regular as in obstructive jaundice and cirrhosis, or hard, irregular, painless and sometimes nodular as in advanced secondary carcinoma). In tricuspid regurgitation, the liver may be felt to pulsate. Occasionally a congenital variant of the right lobe projects down lateral to the gallbladder as a tongue-shaped process, called Riedel’s lobe. Though uncommon, it is important to be aware of this because it may be mistaken either for the gallbladder itself or for the right kidney.

Gallbladder

The gallbladder is palpated in the same way as the liver. The normal gallbladder cannot be felt. When it is distended, however, it forms an important sign and may be palpated as a firm, smooth, or globular swelling with distinct borders, just lateral to the edge of the rectus abdominis near the tip of the ninth costal cartilage. It moves with respiration. Its upper border merges with the lower border of the right lobe of the liver, or disappears beneath the costal margin and therefore can never be felt (Fig. 12.19). When the liver is enlarged or the gallbladder grossly distended, the latter may be felt not in the hypochondrium, but in the right lumbar or even as low down as the right iliac region.

Figure 12.19 Palpation of an enlarged gallbladder, showing how it merges with the inferior border of the liver so that only the fundus of the gallbladder and part of its body can be palpated.

The ease of definition of the rounded borders of the gallbladder, its comparative mobility on respiration, the fact that it is not normally bimanually palpable and that it seems to lie just beneath the abdominal wall helps to identify such a swelling as gallbladder rather than a palpable right kidney. A painless gallbladder can usually be palpated in the following clinical situations:

Figure 12.20 A mucocele of the gallbladder that is distended, pale and thin walled.

The urinary bladder

Normally the urinary bladder is not palpable. When it is full and the patient cannot empty it (retention of urine), a smooth firm regular oval-shaped swelling will be palpated in the suprapubic region and its dome (upper border) may reach as far as the umbilicus. The lateral and upper borders can be readily made out, but it is not possible to feel its lower border (i.e. the swelling is ‘arising out of the pelvis’). The fact that this swelling is symmetrically placed in the suprapubic region beneath the umbilicus, that it is dull to percussion and that pressure on it gives the patient a desire to micturate, together with the signs above, confirm such a swelling as the bladder (Fig. 12.21).

Figure 12.21 Physical signs in retention of urine; a smooth, firm and regular swelling arising out of the pelvis which one cannot ‘get below’ and which is dull to percussion.

In women, however, a mass that is thought to be a palpable bladder has to be differentiated from a gravid uterus (firmer, mobile side to side and vaginal signs different), a fibroid uterus (may be bosselated, firmer and vaginal signs different) and an ovarian cyst (usually eccentrically placed to left or right side).

The aorta and common femoral vessels

In most adults, the aorta is not readily felt, but with practice it can usually be detected by deep palpation a little above and to the left of the umbilicus. In thin patients, particularly women with a marked lumbar lordosis, the aorta is more easily palpable. Palpation of the aorta is one of the few occasions in the abdomen when the fingertips are used as a means of palpation. Press the extended fingers of both hands, held side by side, deeply into the abdominal wall in the position shown in Fig. 12.22; make out the left wall of the aorta and note its pulsation. Remove both hands and repeat the manoeuvre a few centimetres to the right. In this way the pulsation and width of the aorta can be estimated. It is difficult to detect small aortic aneurysms; where a large one is present, its presence and width may be assessed by placing the extended fingertips on either side of it with the palms flat on the abdominal wall and the fingers pointing towards each other. When the fingertips are either side of an aneurysm, it should be clear that they are being separated by each pulsation and not just moved up and down (this latter manoeuvre can involve very deep palpation and the patient should be warned).

Figure 12.22 Palpation of the abdominal aorta.

The common femoral vessels are found just below the inguinal ligament at the mid-point between the anterior superior iliac spine and symphysis pubis. Place the pulps of the right index, middle and ring fingers over this site in the right groin and palpate the wall of the vessel. Note the strength and character of its pulsation and then compare it with the opposite femoral pulse (Fig. 12.23).

Figure 12.23 Palpation of the femoral vessels.

Lymph nodes lying along the aorta (para-aortic nodes) are palpable only when considerably enlarged. They are felt as rounded, firm, often confluent, fixed masses in the umbilical region and epigastrium along the left border of the aorta.

Causes of diagnostic difficulty on palpation

In many patients, especially those with a thin or lax abdominal wall, faeces in the colon may simulate an abdominal mass. The sigmoid colon is frequently palpable, particularly when loaded with hard faeces. It is felt as a firm, tubular structure about 12 cm in length, situated low down in the left iliac fossa, parallel to the inguinal ligament. The caecum is often palpable in the right iliac fossa as a soft, rounded swelling with indistinct borders. The transverse colon is sometimes palpable in the epigastrium. It feels somewhat like the pelvic colon but rather larger and softer, with distinct upper and lower borders and a convex anterior surface. A faecal ‘mass’ will usually have disappeared or moved on repeat examination and may retain an indentation with pressure (not the case with a colonic malignancy).

In the epigastrium, the muscular bellies of rectus abdominis lying between its tendinous intersections can mimic an underlying mass and give rise to confusion. This can usually be resolved by asking the patient to tense the abdominal wall (by lifting the head off the pillow), when the ‘mass’ may be felt to contract.

What to do when an abdominal mass is palpable

When a mass in the abdomen is palpable, first make sure that it is not a normal structure, as described above. Consider whether it could be due to enlargement of the liver, spleen, right or left kidney, gallbladder, urinary bladder, aorta or para-aortic nodes. The aim of examination of a mass is to decide the organ of origin and the pathological nature. In doing this, it is helpful to bear in the mind the following points:

Defining the boundaries of abdominal organs and masses

Detection of ascites and its differentiation from ovarian cyst and intestinal obstruction

There are three common causes of diffuse enlargement of the abdomen:

Percussion rapidly distinguishes between these three, as can be seen in Figure 12.24. Other helpful symptoms or signs which are usually present are listed in Box 12.4.

Figure 12.24 Three types of diffuse enlargement of the abdomen.

The use of ultrasound to detect ascites has shown that quite a lot needs to be present to be detected clinically, probably more than 2 litres. It is unwise and unreliable to diagnose ascites unless there is sufficient free fluid present to give generalized enlargement of the abdomen. The cardinal sign created by ascites is shifting dullness. A fluid thrill may also be present but it would be unwise to diagnose ascites based on this sign without the presence of shifting dullness.

To demonstrate shifting dullness, lie the patient supine. Place your fingers in the longitudinal axis on the midline near the umbilicus and begin percussion, moving your fingers laterally towards the right flank. When dullness is first detected (in normal individuals, dullness is only over the lateral abdominal musculature), keep your fingers in that position and ask the patient to roll onto his left side. Wait a few seconds for any peritoneal fluid to redistribute and, if ascites is present, the percussion note should have become resonant. This shift of the area of dullness can be confirmed by finding the left border of dullness with the patient still on his left side and seeing if it shifts when the patient returns to the supine position, or by repeating the original manoeuvre but towards the other side of the abdomen.

To elicit a fluid thrill, the patient is again laid supine. Place one hand flat over the lumbar region of one side, and get an assistant to put the side of their hand longitudinally and firmly in the midline of the abdomen. Then flick or tap the opposite lumbar region (Fig. 12.25). A fluid thrill or wave is felt as a definite and unmistakable impulse by the detecting hand held flat in the lumbar region. (The purpose of the assistant’s hand is to dampen any impulse that may be transmitted through the fat of the abdominal wall.) As a rule, a fluid thrill is felt only when there is a large amount of ascites present which is under tension, and it is not a very reliable sign.

Figure 12.25 Eliciting a fluid thrill. (The hand in the middle of the abdomen is that of an assistant.)

Bowel sounds

The stethoscope should be placed on one site on the abdominal wall (just to the right of the umbilicus is best) and kept there until sounds are heard. It should not be moved from site to site. Normal bowel sounds are heard as intermittent low- or medium-pitched gurgles interspersed with an occasional high-pitched noise or tinkle.

In simple acute mechanical obstruction of the small bowel, the bowel sounds are excessive and exaggerated. Frequent, loud, low-pitched gurgles (borborygmi) are heard, often rising to a crescendo of high-pitched tinkles and occurring in a rhythmic pattern with peristaltic activity. The presence of such sounds occurring at the same time as the patient experiences bouts of colicky abdominal pain is highly suggestive of small bowel obstruction. In between the bouts of peristaltic activity and colicky pain, the bowel is quiet and no sounds are heard on auscultation.

If obstruction progresses leading to bowel necrosis, peristalsis ceases and sounds lessen in volume and frequency. In generalized peritonitis, bowel activity rapidly disappears and a state of paralytic ileus ensues, with gradually increasing abdominal distension. The abdomen is ‘silent’ but one must listen for several minutes before being certain that there are no sounds. Frequently, towards the end of this period, a short run of faint, very high-pitched tinkling sounds is heard. This represents fluid spilling over from one distended loop to another and is characteristic of ileus.

A succussion splash may be heard without a stethoscope and also on auscultation, when there is pyloric stenosis, in advanced intestinal obstruction with grossly distended loops of bowel and in paralytic ileus. Lie the patient supine and place the stethoscope over the epigastrium. Shake the patient briskly from side to side and, if the stomach is distended with fluid, a splashing sound will be heard.

Vascular bruits

Listen for bruits by light application of the stethoscope above and to the left of the umbilicus (aorta), the iliac fossae (iliac arteries), epigastrium (coeliac or superior mesenteric arteries), laterally in the mid-abdomen (renal arteries) or over the liver (increased blood flow in liver tumours – classically primary liver cancer). If an arterial bruit is heard, it is a significant finding which indicates turbulent flow in the underlying vessel, due to stenosis, aneurysm or a malignant circulation

What to do if a patient complains of a lump in the groin

A lump in the groin or scrotum is a common clinical problem in all age groups. Most lumps in the groin are due either to herniae or to enlarged inguinal nodes; inguinal herniae are considerably more common than femoral, with an incidence ratio of 4 : 1. In the scrotum, hydrocele of the tunica vaginalis or a cyst of the epididymis are common causes of painless swelling; acute epididymo-orchitis is the most frequent cause of a painful swelling. Generalized diseases such as lymphoma may present as a lump in the groin. Usually the diagnosis of a lump in the groin or scrotum can be made simply and accurately. Remember that the patient should be examined not only lying down, but also standing up.

Ask the patient to stand in front of you, get him to point to the side and site of the swelling and note whether it extends into the scrotum. Get him to turn his head away from you and give a loud cough; look for an expansile impulse and try to decide whether it is above or below the crease of the inguinal ligament. If an expansile impulse is present on inspection, it is likely to be a hernia, so move to whichever side of the patient the lump in the groin is on. Stand beside and slightly behind the patient. If the right groin is being examined, place the left hand over the right buttock to support the patient, the fingers of the right hand being placed obliquely over the inguinal canal. Now ask the patient to cough again. If an expansile impulse is felt then the lump must be a hernia.

Next decide whether the hernia is inguinal or femoral. The best way to do this is to determine the relationship of the sac to the pubic tubercle. To locate this structure, push gently upwards from beneath the neck of the scrotum with the index finger (Fig. 12.27) but do not invaginate the neck of the scrotum as this is painful. The tubercle will be felt as a small bony prominence 2 cm from the midline on the pubic crest. In thin patients, the tubercle is easily felt but this is not so in the obese. If difficulty is found, follow up the tendon of adductor longus, which arises just below the tubercle.

Figure 12.27 Locating the pubic tubercle. Note the position of the examiner, at the side of the patient, with one hand supporting the buttock.

If the hernial sac passes medial to and above the index finger placed on the pubic tubercle, then the hernia must be inguinal in site; if it is lateral to and below, then the hernia must be femoral in site.

If it has been decided that the hernia is inguinal, then one needs to know these further points:

Figure 12.28 Left hand: index finger occluding the deep inguinal ring. Right hand: index finger on the pubic tubercle.

Apart from a femoral hernia, the differential diagnosis of an inguinal hernia includes a large hydrocele of the tunica vaginalis, a large cyst of the epididymis (one should be able to ‘get above’ and feel the upper border of both of these in the scrotum), an undescended or ectopic testis (there will be an empty scrotum on the affected side), a lipoma of the cord and a hydrocele of the cord.

In considering the differential diagnosis of a femoral hernia, one must think not only of an inguinal hernia but of a lipoma in the femoral triangle, an aneurysm of the femoral artery (expansile pulsation will be present), a saphenovarix (the swelling disappears on lying down, has a bluish tinge to it, there are often varicose veins present and there may be a venous hum), a psoas abscess (the mass is fluctuant, and may be compressible beneath the inguinal ligament to appear above it in the iliac fossa) and an enlarged inguinal lymph node. Whenever the latter is found, the feet, legs, thighs, scrotum, perineum and the pudendal and perianal areas must be carefully scrutinized for a source of infection or primary tumour.

The examination is completed by following the same scheme in the opposite groin.

Inspection

Separate the buttocks carefully and inspect the perianal area and anus. Note the presence of any abnormality of the perianal skin, such as inflammation, which may vary in appearance from mild erythema to a raw, red, moist, weeping dermatitis or, in chronic cases, thickened white skin with exaggeration of the anal skin folds. The latter form anal skin tags, which may follow not only severe pruritus but also occur when prolapsing piles have been present over a period of time. Tags should not be confused with anal warts (condylomata acuminata), which are sessile or pedunculated papillomata with a red base and a white surface. Anal warts may be so numerous as to surround the anal verge, and even extend into the anal canal. Note any ‘hole’ or dimple near the anus with a tell-tale bead of pus or granulation tissue surrounding it, which represents the external opening of a fistula-in-ano. It is usually easy to distinguish a fistula-in-ano from a pilonidal sinus, where the opening lies in the midline of the natal cleft but well posterior to the anus.

There are a number of painful anorectal conditions that can usually be diagnosed readily on inspection. An anal fissure usually lies directly posterior in the midline. The outward pathognomonic sign of a chronic fissure is a tag of skin at the base (sentinel pile). If pain allows, the fissure can easily be demonstrated by gently drawing apart the anus to reveal the tear in the lining of the anal canal.

A perianal haematoma (thrombosed external pile) occurs as a result of rupture of a vein of the external haemorrhoidal plexus. It is seen as a small (1 cm), tense, bluish swelling on one aspect of the anal margin and is exquisitely tender to the touch. In prolapsed strangulated piles, there is gross swelling of the anal and perianal skin, which looks like oedematous lips, with a deep red or purple strangulated pile appearing in between, and sometimes partly concealed by, the oedema of the swollen anus. In a perianal abscess, an acutely tender, red, fluctuant swelling is visible which deforms the outline of the anus. It is usually easy to distinguish this from an ischiorectal abscess where the anal verge is not deformed, the signs of acute inflammation are often lacking and the point of maximum tenderness is located midway between the anus and ischial tuberosity.

Note the presence of any ulceration. Finally, if rectal prolapse is suspected, ask the patient to bear down (as if trying to pass stool) and note whether any pink rectal mucosa or bowel appears through the anus, or whether the perineum itself bulges downwards. Downward bulging of the perineum during straining at bending down, or in response to a sudden cough, indicates weakness of the pelvic floor support musculature, usually due to denervation of these muscles. This sign is often found in women after childbirth, in women with faecal or urinary incontinence and in patients with severe chronic constipation.

Digitial rectal examination (palpation)

Put a generous amount of lubricant on the gloved index finger of the right hand, place the pulp of the finger (not the tip) flat on the anus (Figs 12.30 and 12.31) and press firmly and slowly (flexing the finger) in a slightly backwards direction. After initial resistance, the anal sphincter relaxes and the finger can be passed into the anal canal. If severe pain is elicited when attempting this manoeuvre, then further examination should be abandoned as it is likely the patient has a fissure and the rest of the examination will be very painful and unhelpful.

Figure 12.30 Correct method for insertion of the index finger in rectal examination. The pulp of the finger is placed flat against the anus.

Figure 12.31 Incorrect method of introduction of the finger into the anal canal.

Feel for any thickening or irregularity of the wall of the canal, making sure that the finger is turned through a full circle (180° each way). Assess the tone of the anal musculature; it should normally grip the finger firmly. If there is any doubt, ask the patient to contract the anus on the examining finger. A cough will induce a brisk contraction of the external anal sphincter which should be readily appreciated. In the old and infirm with anal incontinence or prolapse, almost no appreciable contraction will be felt. With experience it is usually possible to feel a shallow groove just inside the anal canal which marks the dividing line between the external and internal sphincter. The anorectal ring may be felt as a stout band of muscle surrounding the junction between the anal canal and rectum.

Now pass the finger into the rectum. The examiner’s left hand should be placed on the patient’s right hip and later it can be placed in the suprapubic position to exert downward pressure on the sigmoid colon. Try to visualize the anatomy of the rectum, particularly in relation to its anterior wall. The rectal wall should be assessed with sweeping movements of the finger through 360°, 2, 5 and 8 cm inwards or until the finger cannot be pushed any higher into the rectum. Repeat these movements as the finger is being withdrawn. In this way it is possible to detect malignant ulcers, proliferative and stenosing carcinomas, polyps and villous adenomas. The hollow of the sacrum and coccyx can be felt posteriorly. Laterally, on either side, it is usually possible to reach the side walls of the pelvis. In men, one should feel anteriorly for the rectovesical pouch, seminal vesicles (normally not palpable) and the prostate. In a patient with a pelvic abscess, however, pus gravitates to this pouch, which is then palpable as a boggy, tender swelling lying above the prostate. Malignant deposits will feel hard and, in infection of the seminal vesicles, these structures become palpable as firm, almost tubular swellings deviating slightly from the midline just above the level of the prostate.

Assessment of the prostate gland is important. It forms a rubbery, firm swelling about the size of a large nut. Run the finger over each lateral lobe, which should be smooth and regular. Between the two lobes lies the median sulcus, which is palpable as a faint depression running vertically between each lateral lobe. While it is possible to say on rectal examination that a prostate is enlarged, accurate assessment of its true size only comes with a lot of experience. In carcinoma of the prostate, the gland loses its rubbery consistency and becomes hard, while the lateral lobes tend to be irregular and nodular and there is distortion or loss of the median sulcus.

The cervix is felt as a firm, rounded mass projecting back into the anterior wall of the rectum. This is often a disconcerting finding for the inexperienced. The body of a retroverted uterus, fibroid mass, ovarian cyst, malignant nodule or a pelvic abscess may all be palpated in the pouch of Douglas (rectouterine pouch), which lies above the cervix. This aspect of rectal examination forms an essential part of pelvic assessment in female patients.

On withdrawing the finger after rectal examination, look at it for evidence of mucus, pus and blood. If in doubt, wipe the finger on a white swab. Finally, make sure to wipe the patient clean before telling the patient that the examination is completed, and also telling him to be careful as he rolls to the supine position as they will be very near the edge of the couch or bed.

Site

When the visceral peritoneum is predominantly involved in an acute process, pain is often referred in a developmental distribution, and so when assessing acute abdominal pain it is often helpful to think of the embryological development of the gut. Foregut structures are proximal to the duodenojejunal flexure and pain from here will often be felt in the upper abdomen. The small bowel and the colon around to the mid-transverse originate from the mid-gut and may produce pain in the periumbilical region, such as in the early phases of acute appendicitis. Pain from structures developing from the hind-gut will be felt in the lower abdomen. As any disease process advances and the parietal peritoneum is irritated, pain is felt at the site of the affected organ, such as in the right iliac fossa in the later stages of acute appendicitis.

Ask the patient to point to the site of maximal pain with one finger. If pain is experienced mostly in the upper abdomen, think of perforation of a gastric or duodenal ulcer, cholecystitis or pancreatitis. If pain is located in the mid-abdomen, disease of the small bowel is likely. Pain in the right iliac fossa is commonly due to appendicitis and pain in the left iliac fossa to diverticulitis. In women, the menstrual history is important as low abdominal pain of acute onset is often due to salpingitis, but rupture of an ectopic pregnancy should also be considered. The coexistence of severe back and abdominal pain may indicate a ruptured abdominal aneurysm or a dissecting aneurysm.

Severity

Try to assess the severity of the pain. Ask whether it keeps the patient awake. In women who have had children, compare the severity with labour pains. Sometimes comparison to the pain of a fractured bone is useful.

Radiation

If pain radiates from the right subcostal region to the shoulder or to the interscapular region, inflammation of the gallbladder (cholecystitis) is a likely diagnosis. If pain begins in the loin but then is felt in the lumbar region, a renal stone or renal infection should be considered. Pain beginning in the loin and radiating to the groin is likely to be due to a ureteric calculus and umbilical pain radiating to the right iliac fossa is usually due to appendicitis. Central upper abdominal pain, later radiating through to the back, is common in pancreatitis.

Character and constancy

Constant severe pain felt over many hours is likely to be due to infection. For example, diverticulitis or pyelonephritis can present in this manner. Colicky pain, on the other hand (i.e. pain lasting a few seconds or minutes and then passing off, leaving the patient free of pain for a further few minutes), is typical of small bowel obstruction. If such pain is suddenly relieved after a period of several hours of severe pain, perforation of a viscus should be considered. Large bowel obstruction produces a more constant pain than small bowel obstruction, but colic is usually prominent. Biliary and renal colic are also of variable severity, but with a longer period of variation than small bowel colic, and coming on more quickly than it wears off.

Mode of onset

In obstruction from mechanical disorders such as that due to biliary or ureteric stone, or obstruction of the bowel from adhesions or volvulus, the onset of colicky pain is usually sudden. It is often related to activity or movement in the previous few hours. In infective and inflammatory disorders, the pain usually has a slower onset, sometimes over several days, and there is no relation to activity. Recent ingestion of a rich, heavy meal sometimes precedes pancreatitis. Alcohol excess or the ingestion of aspirin or non-steroidal anti-inflammatory drugs are sometimes precipitating features in patients presenting with perforated peptic ulcer or with haematemesis.

Relieving features

Abdominal pain relieved by rest suggests an infective or inflammatory disorder. Pancreatic pain is classically relieved by sitting forward.

Vomiting

A history of vomiting is not in itself very helpful because vomiting occurs as a response to pain of any type. However, effortless projectile vomiting often denotes pyloric stenosis or high small bowel obstruction. In peritonitis, the vomitus is usually small in amount but vomiting is persistent. There may be a faeculent smell to the vomitus when there is low small bowel obstruction. Persistent vomiting with associated diarrhoea strongly suggests gastroenteritis. It is unusual for patients with a perforated ulcer to vomit.

Micturition

Increased frequency of micturition occurs both in urinary tract infections and in other pelvic inflammatory disorders as well as in patients with renal infections or ureteric stones. In the latter, haematuria commonly occurs.

Appetite and weight

In patients with a chronic underlying disorder, such as abdominal cancer, there may be a history of anorexia and weight loss, although weight loss also occurs in a variety of other disorders. Sudden loss of appetite clearly indicates a disorder of sudden onset.

Other features

It is important to note whether there have been previous episodes of abdominal pain and whether or not they have been severe. The patient may have noticed swellings at the site of a hernial orifice, indicating the likelihood of an obstructed hernia, or there may be a history of blunt or penetrating abdominal trauma. Sometimes the patient may be aware of increasing abdominal distension, a phenomenon indicating intestinal obstruction or paralytic ileus probably associated with an inflammatory or infective underlying bowel disorder. Food poisoning may be suggested by a history of ingestion of unusual foods or a meal in unfamiliar surroundings. The menstrual history should never be forgotten, particularly in relation to the possibility of an ectopic pregnancy. Enquiry should always be made as to a purulent vaginal discharge, indicating salpingitis, or of discharge of mucus, pus or blood from the rectum, suggesting inflammatory bowel disease.

Guarding

Guarding is an involuntary reflex contraction of the muscles of the abdominal wall overlying an inflamed viscus and peritoneum, producing localized rigidity. It indicates localized peritonitis. What is felt on examination is spasm of the muscle, which prevents palpation of the underlying viscus. Guarding is seen classically in uncomplicated acute appendicitis. It is very important to distinguish this sign from voluntary contraction of muscle.

Rigidity

Generalized or ‘board-like’ rigidity is an indication of diffuse peritonitis. It can be looked upon as an extension of guarding, with involuntary reflex rigidity of the muscles of the anterior abdominal wall. It is quite unmistakable on palpation, as the whole abdominal wall feels hard and ‘board like’, precluding palpation of any underlying viscus. The least downward pressure with a palpating hand in a patient with generalized rigidity produces severe pain. It may be differentiated from voluntary spasm by getting the patient to breathe: if there is voluntary spasm, the abdominal wall will be felt to relax during expiration.

Rebound tenderness

Rebound tenderness is present if, when palpating slowly and deeply over a viscus and then suddenly releasing the palpating hand, the patient experiences sudden pain. Rebound tenderness is not always a reliable sign and should be interpreted with caution, particularly in those patients with a low pain threshold, but is often a useful adjunct to detecting peritoneal inflammation.

Percussion

The absence of dullness over the liver can indicate free intraperitoneal gas and hence a perforated viscus.

Radiology

A plain X-ray of the abdomen is an important immediate investigation in the diagnosis of the acute abdomen, especially in suspected perforation or obstruction (Fig. 12.32).

Figure 12.32 Plain X-ray of the abdomen. Obstruction of the large bowel due to carcinoma of the sigmoid colon. Most of the colon is dilated with gas, indicating obstruction, but there appears to be no gas below the sigmoid region.

Faecal amount

Note whether the stools are copious or scanty, and whether they are hard, formed, semiformed or liquid.

Faecal colour

Black stools may be produced by altered blood or the ingestion of iron or bismuth. In haemorrhage occurring high up in the intestine, the altered blood makes the stools dark, tarry-looking and with the characteristic and offensive smell of melaena. Pallor of the stools may be due to lack of entrance of bile into the intestine, as in obstructive jaundice; to dilution and rapid passage of the stool through the intestine as in diarrhoea; or to an abnormally high fat content as in malabsorption.

Faecal odour

The stools in jaundice are often very offensive. Cholera stools, on the other hand, contain very little organic matter, and are almost free from odour. The stools of acute bacillary dysentery are almost odourless, while those of amoebic dysentery have a characteristic odour, something like that of semen. Melaena stools have a characteristic smell.

Abnormal stools

Watery stools are found in all cases of profuse diarrhoea and after the administration of purgatives. In cholera, the stools – known as rice-water stools – are colourless, almost devoid of odour, alkaline in reaction and contain a number of small flocculi consisting of shreds of epithelium and particles of mucus. Purulent or pus-containing stools are found in severe dysentery or ulcerative colitis. Slimy stools are due to the presence of an excess of mucus, and point to a disorder of the large bowel. The mucus may envelop the faecal masses or may be intimately mixed with them.

Bloody stools vary in appearance according to the site of the haemorrhage. If the bleeding takes place high up, the stools look like tar. In an intussusception, they may look like redcurrant jelly. Large bowel bleeding above the rectum may produce darker red visible blood whereas bleeding from the rectum or anus may streak the faeces bright red, and haemorrhoidal bleeding may just be found on the toilet paper. A brisk upper-GI bleed can lead to bright red rectal bleeding.

The stools of bacillary dysentery consist at first of faecal material mixed with blood and pus, later of blood and pus without faecal material. Those of amoebic dysentery characteristically consist of fluid faecal material, mucus and small amounts of blood. The stools of steatorrhoea are very large, pale and putty-like or porridge-like, sometimes frothy with a visible oily film, and often float. They are apt to stick to the sides of the toilet and are difficult to flush away.

Tests for faecal occult blood

Several methods are available. For reasons of ease of use and safety, the guaiac test (Haemoccult^®) is the most widely used. A filter paper impregnated with guaiac turns blue in the presence of haemoglobin when hydrogen peroxide is added. The test depends on the oxidation of guaiac in the presence of haemoglobin. Other substances with peroxidase activity, including dietary substances such as bananas, pineapple, broccoli and radishes, can produce a false positive reaction, and ascorbic acid may cause false negative results. Therefore, dietary preparation is necessary for accurate screening testing; for example, when screening a population in the early detection of colonic cancer. In ordinary clinical use, the test is sensitive to faecal blood losses of about 20 ml per day. This test can be used on patients on a normal diet, but it may not detect small amounts of GI bleeding. The test may be negative in the presence of lesions which bleed intermittently or slightly, particularly those situated in the upper GI tract. Spectroscopic methods and isotopic methods using radiolabelled red cells that can localize the source of bleeding in the gut are also available.

Tests for faecal fat

Fat is present in food as neutral fat or triglyceride. It is split to greater or lesser degrees by lipases, mainly of the pancreas, into glycerol and fatty acids. Some of the fatty acids, if unabsorbed, combine with bases to form soaps. Fat may, therefore, be found in the faeces as neutral fat, fatty acids and soaps.

The estimation of the proportion of split and unsplit fats present has been found unreliable as a method of distinguishing pancreatic from non-pancreatic steatorrhoea because of the effects of bacterial activity on neutral fats.

For the estimation of the fat in the stools, the patient may be placed on a diet containing 50 g of fat per day. The fat present in the stools collected over at least 3 days is then estimated and should not exceed 6 g/day (11-18 mmol/day). It has been found that equally reliable results are obtained if the patient eats a normal diet, provided a 3-5 day collection is made.

Faecal fat testing has largely been replaced by the measurement of faecal elastase which, if reduced below a reference value, usually indicates pancreatic exocrine insufficiency.

Stool microbiology

Reliable microbiological examination of the stool is vital for accurate diagnosis of acute and chronic diarrhoea. All stool samples for microbiological examination should get to the laboratory as fresh as possible, and if amoebic or similar infection is suspected then microscopy should be performed with the stool still as close to body temperature as possible.

Any microbiological finding must be correlated with the history, as many patients are healthy carriers of organisms that can be pathogenic in other situations. If Clostridium difficile infection is suspected in a patient with diarrhoea following the use of antibiotics, the laboratory must be asked to look for the clostridium toxin in preference to the organism.

Plain radiographs

Plain radiographs of the chest and abdomen with the patient supine and in the erect position are of great value in cases of suspected peritonitis due to a perforated viscus, when gas may be seen under the diaphragm, usually on the right side (Fig. 12.36). A plain abdominal X-ray is useful in suspected intestinal obstruction or ileus when dilated bowel loops may be seen with fluid levels appearing on the erect X-ray.

Figure 12.36 Plain X-ray of the chest showing gas under the right and left diaphragms after perforation of the duodenal ulcer. The patient was admitted in shock with abdominal pain and abdominal rigidity.

Barium swallow

The direct observation of the passage of a radiopaque barium solution through the pharynx and oesophagus into the stomach remains an important investigation of dysphagia. In addition to structural abnormalities such as neoplasia or stricture, disorders of motor function can be detected which might otherwise escape diagnosis. Lack of progress of barium through an apparently normal lower oesophageal sphincter on swallowing in a patient with dysphagia usually indicates the presence of achalasia, a disorder of neuromuscular coordination of the oesophageal body and failure of the lower sphincter to relax.

A careful radiological assessment of the stomach and duodenum which has been coated with swallowed barium and then inflated with a gas-forming tablet has the ability to demonstrate benign ulcers and tumours, as well as assessing gastric outflow, but the ability to take endoscopic biopsies has meant that barium radiology is now a secondary investigation to upper-GI endoscopy.

Barium follow-through X-rays

The small intestine may be studied by taking films of the abdomen at intervals after swallowing barium contrast. Abnormalities in the transit time to the colon and in small bowel pattern (e.g. dilatation, narrowing, increase in transverse barring or flocculation) may be demonstrated in malabsorption. Areas of narrowing with proximal dilatation, fistulae and mucosal abnormalities may be produced by Crohn’s disease. Small bowel diverticula or neoplasms may also be demonstrated. The amount and type of barium used for examination of the stomach/duodenum and of the small bowel is different, and so a barium follow-through should be requested as a specific examination and not as an add-on to a barium meal.

Small-bowel enema

This is an alternative to the barium follow-through examination and involves intubating the duodenum and passing small quantities of a non-flocculating barium suspension down the tube. This method is particularly valuable for detecting isolated focal lesions and strictures.

Radioisotope studies

In inflammatory bowel disease, the location of the disease, and a measure of its activity, can be obtained by radioisotope studies using the patient’s own white blood cells that have been radiolabelled.

Small-intestinal endoscopy and biopsy

Samples of small-intestinal mucosa are valuable for histological diagnosis in various types of malabsorption. Direct biopsy of the lower duodenum at conventional upper-GI endoscopy is usually sufficient for diagnosis of coeliac disease but jejunal tissue can also be obtained using push-type flexible enteroscopes. Endoscopic techniques for biopsying have now largely replaced remote biopsy by Crosby capsule. If necessary, full-thickness jejunal biopsies, useful for diagnosing neuromuscular gut disorders, can be obtained by laparoscopy. Excellent endoscopic images of the whole of the small bowel can now be obtained by wireless capsule endoscopy but, as yet, biopsies are not possible by this method.

If coeliac disease is suspected, serum antibodies to gliadin, reticulin, endomysial and tissue transglutaminidase antigens are a useful screening test (provided there is no IgA deficiency), but a biopsy is essential to fully complete or fully exclude the diagnosis. The low-power view of the villi is as important as the detailed histology. Other malabsorption problems such as Whipple’s disease and chronic giardiasis may also be seen on duodenal biopsy.

Magnetic resonance scanning

Increasingly, magnetic resonance scanning is replacing barium radiology for assessing areas of stricturing and inflammation in the small bowel.

Proctoscopy

The anal canal and lower rectum can be readily visualized with a rigid proctoscope. Place the patient in the position described for rectal examination and gently pass the lubricated instrument to its full depth. Remove the obturator and inspect the mucosa as the instrument is slowly withdrawn. Haemorrhoids are seen as reddish/blue swellings which bulge into the lumen of the instrument. Asking the patient to strain down as the proctoscope is withdrawn exaggerates the haemorrhoids. The internal opening of an anal fistula, an anal or low rectal polyp and a chronic anal fissure are other abnormalities that may be seen.

Rigid sigmoidoscopy and other tests in chronic diarrhoea

It is often necessary to examine the rectum and colon more fully than is possible by proctoscopy and, in such cases, the rigid sigmoidoscope is employed. Sigmoidoscopy requires skill and experience. In accomplished hands, the instrument can be passed for 30 cm, although no more than the rectum can be seen in other patients. The procedure causes relatively little discomfort and anaesthesia is unnecessary.

Proctitis, polyps and carcinomas may be seen and biopsies taken. Sigmoidoscopy is particularly useful in the differential diagnosis of diarrhoea of colonic origin. Granularity, loss of vascular pattern and ulceration with bleeding may indicate the presence of ulcerative colitis, aphthous ulceration may suggest Crohn’s disease, and multiple rounded white macules may be diagnostic of pseudomembranous colitis due to Clostridium difficile toxin usually following antibiotic treatment. In suspected amoebic dysentery, the mucous membrane should be inspected and portions of mucus and scrapings from the ulcerated mucosa may be removed and examined microscopically for amoebic cysts.

Urine tests for purgative abuse are useful in the investigation of persistent unexplained diarrhoea.

Barium enema

Prior to barium enema, the patient must have his bowel prepared with a vigorous laxative, as residual stool or fluid can be mistaken for polyps and other lesions. Impending obstruction is a contraindication to this laxative preparation. A plain X-ray of the abdomen should always be taken in patients with suspected perforation or obstruction before considering a contrast study (see Fig. 12.32).

Barium suspension is introduced via a tube into the rectum as an enema and manipulated around the rest of the colon to fill it. Screening is performed by a radiologist and films taken. The barium is then evacuated and further films taken. By this means, obstruction to the colon, tumours, diverticular disease, fistulae and other abnormalities can be recognized.

Following evacuation, air is introduced into the colon. This improves visualization of the mucosa and is especially valuable for detecting small lesions such as polyps and early tumours (Figs 12.37 and 12.38).

Figure 12.37 Barium enema with air contrast. The right colon is outlined by barium sulphate, and the rectum, left colon and part of the transverse colon are outlined by air with a thin mucosal layer of barium sulphate. Note the normal haustral pattern in the colon and the smooth appearance of the rectum. The anal canal can also be seen.

Figure 12.38 Barium enema with air contrast. In this patient with ulcerative colitis, the normal mucosal pattern, and the haustra themselves, have been obliterated. The patient is lying on his right side so that there are clear fluid levels in the barium sulphate suspension in the bowel.

Patients often find the preparation and procedure uncomfortable and there is a very small risk of perforating the colon.

Colonoscopy and flexible sigmoidoscopy

As in the upper gut, the use of flexible fibreoptic and video instruments has revolutionized the investigation of the colon. Both sigmoidoscopes and colonoscopes are available. The former instrument may be employed in an outpatient setting after a simple enema preparation; the latter requires more extensive colon preparation (similar to barium enema X-ray) and sedation but is also an outpatient procedure. These techniques are invaluable for obtaining tissue for diagnosis of inflammatory and neoplastic disease and for removal of neoplastic polyps (Figs 12.39 and 12.40). Dilatation of strictures, stenting, laser or other thermal treatments of obstructing tumours can also be applied during endoscopy.

Figure 12.39 View of colonic epithelium at colonoscopy, showing severe ulcerative colitis with extensive ulceration and bleeding.

Figure 12.40 Colonoscopic view of a tubulovillous adenoma.

A skilled colonoscopist can reach the caecum in 95% of examinations attempted, and the terminal ileum in 50%. There is a small risk (1 : 1000) of colonic perforation associated with the colonoscopy, and of respiratory arrest with the sedatives.

Biochemical tests in liver disorders

These are used in the differential diagnosis of jaundice, to detect liver cell damage in other disorders and to monitor the results of medical and surgical treatments of the liver, pancreas and biliary systems. These include plasma bilirubin, alkaline phosphatase, serum aminotransferases, plasma proteins and prothrombin time. Serum gamma glutamyl transferase levels are especially sensitive to liver dysfunction as, for example, in alcohol-related liver disease.

Smooth muscle antibodies are commonly present in the blood in chronic active hepatitis, and other autoantibody studies are used in the investigation of chronic inflammatory liver disease. Antimitochondrial antibodies are found in the blood in primary biliary cirrhosis in over 90% of cases.

Liver disease due to excess iron or copper accumulation can be detected by measurements of these metals and their carrier proteins in blood (or urine for copper). In primary haemochromatosis, genetic studies are very useful in diagnosis. Serum alpha-foetoprotein is often raised in primary liver cell cancer, which can complicate any cause of cirrhosis, or the carriage of hepatitis B or C.

Viral hepatitis

The presence of ongoing carriage of viral hepatitis is initially detected by antigen testing (for hepatitis B) and by antibody testing for hepatitis C, D and E. Active infection is detected by finding IgM antibody (for hepatitis A, B, D and E), and by polymerase chain reaction (PCR) testing for the viral RNA (hepatitis C). At least two antigens and antibodies of hepatitis B can be detected (surface and e) which give information about activity and ongoing disease and, in the latter, detection of the viral DNA is helpful.

Needle biopsy of liver

Percutaneous needle biopsy is the standard technique for obtaining liver tissue for histological examination. While needle biopsy can be conducted under local anaesthesia (sometimes with mild sedation), it should be carried out only in hospital by fully experienced staff. Generally the method is safe and reliable but there is a tiny but definite mortality from the procedure due to leakage of bile and/or blood into the peritoneal cavity from the puncture site. The procedure should therefore always be regarded as a potentially dangerous investigation for which there should be a clear beneficial indication for the patient, and should be performed by an appropriately trained operator. Liver biopsy under ultrasound control can allow targeting of specific abnormalities and give confidence of a safer procedure. Contraindications to biopsy include patients with abnormal clotting times or platelet numbers, obstructive jaundice or ascites.