Internal gas bubbles, which although uncommon, are very specific for splenic abscess
Multiloculated appearance seen with liver abscesses possible, but less common with splenic abscess
May extend to subcapsular location and may rarely cause splenic rupture with generalized peritonitis
• Fungal microabscesses on CECT
Multiple small hypodense lesions measuring a few mm
Multiple punctate splenic calcifications after treatment
• Echinococcal (hydatid) cyst on CECT
Complex cyst with multiple low density “daughter” cysts and thick, enhancing wall (“cyst within a cyst”)
Serpiginous, linear densities within cyst due to collapsed parasitic membranes (water lily sign)
May demonstrate thick peripheral calcification or internal wavy, curvilinear calcification in chronic setting
TOP DIFFERENTIAL DIAGNOSES
• Splenic infarct
• Splenic tumor
• Splenic trauma
• Infiltrating disorders
PATHOLOGY
• Multiple different causes for splenic pyogenic abscesses
Generalized septicemia, septic emboli (usually in setting of endocarditis with mitral &/or aortic valve vegetations), or secondary infection of traumatic splenic hematoma or infarct
Other predisposing risk factors: Recent surgery, other abdominal infections, intravenous drug abuse, immunodeficiency, malignancy or hematologic disorders, trauma, diabetes, and pancreatitis
• Most fungal microabscesses occur in setting of immunosuppression, HIV/AIDS, or hematologic disorders
• Echinococcal infections occur due to infection with tapeworm (Echinococcus granulosus)
(Left) Axial CECT shows a multiloculated mass within the spleen that proved to be a pyogenic abscess. Such large abscesses are unusual in the spleen, especially in the absence of prior splenic infarction.
(Right) Axial CECT in a patient with a recent history of traumatic injury to the spleen and a new fever demonstrates a rim-enhancing fluid collection with an air-fluid level , consistent with a splenic abscess. The patient was treated with percutaneous drainage and antibiotics.
(Left) Axial CECT in a patient with HIV/AIDS who was admitted with fever and weight loss demonstrates microabscesses throughout the spleen. The patient deteriorated rapidly, and multiple tuberculous abscesses were identified at autopsy.
(Right) Axial CECT shows a splenic hydatid cyst with additional similar lesions in the liver and peritoneal cavity , many of which have calcified walls. This patient had a prior rupture of a hepatic hydatid cyst with diffuse spread throughout the abdomen.
TERMINOLOGY
Definitions
• Splenic abscess: Collection of liquefied pus within splenic parenchyma
IMAGING
General Features
• Best diagnostic clue
Rounded low-attenuation complex fluid collection with mass effect
• Location
Variable: May be located anywhere within splenic parenchyma
• Size
Variable: Typically 3-5 cm for pyogenic abscesses; < 1.5 cm for microabscesses (often fungal)
• Morphology
Rounded cystic mass with irregular borders
– May have multiple locules similar to cluster sign of hepatic pyogenic abscess
– Internal septations common
– Exerts mass effect on splenic capsule
Radiographic Findings
• Radiography
Very rarely gas bubbles within abscess may be visualized on radiographs
Often associated with left lower lobe atelectasis and left pleural effusion on chest radiograph
May extend to subcapsular location and may rarely cause splenic rupture with generalized peritonitis
within the spleen that proved to be a pyogenic abscess. Such large abscesses are unusual in the spleen, especially in the absence of prior splenic infarction.
demonstrates a rim-enhancing fluid collection with an air-fluid level 
, consistent with a splenic abscess. The patient was treated with percutaneous drainage and antibiotics.
throughout the spleen. The patient deteriorated rapidly, and multiple tuberculous abscesses were identified at autopsy.
with additional similar lesions in the liver and peritoneal cavity 
, many of which have calcified walls. This patient had a prior rupture of a hepatic hydatid cyst with diffuse spread throughout the abdomen.
Complex cyst with multiple low density “daughter” cysts and thick, enhancing wall composed of fibrous tissue (“cyst within a cyst” appearance)
Serpiginous, linear hypodense bands within cyst due to collapsed parasitic membranes (water lily sign)
