Chapter 64 Dermatologic emergencies
1. “Dermatologic emergencies” sounds like an oxymoron. Are there dermatologic emergencies?
Yes. Several groups of diseases in dermatology are emergencies. In some, the skin is the primary organ affected (e.g., pemphigus vulgaris) and, in others, the cutaneous manifestations are an important diagnostic finding of a severe underlying condition (e.g., meningococcemia). Rapid recognition and diagnosis of dermatologic emergencies are important because these conditions are often acutely lethal but can be treated successfully if the diagnosis is made early in the disease course.
2. What are the major groups of dermatologic emergencies?
• Vesiculobullous disorders and drug reactions (e.g., Stevens-Johnson syndrome, toxic epidermal necrolysis, pemphigus vulgaris)
• Autoimmune disorders (e.g., acute cutaneous eruption of systemic lupus erythematosus, juvenile rheumatoid arthritis)
Vesiculobullous disorders and drug reactions
3. How does toxic epidermal necrolysis differ from the Stevens-Johnson syndrome or erythema multiforme major?
Toxic epidermal necrolysis (TEN) and Stevens-Johnson syndrome are commonly confused entities, in part because many clinicians use the two terms interchangeably. Because these two diseases have significantly different prognoses and treatments, it is important to differentiate between them (Table 64-1). The diseases can usually be distinguished by their clinical presentation (Fig. 64-1), histologic findings, and course.
Table 64-1. Clinicopathologic Features of Toxic Epidermal Necrolysis (TEN) versus Stevens-Johnson Syndrome (SJS)
| TEN | SJS | |
|---|---|---|
| Maximal intensity | 1–3 days | 7–15 days |
| Skin pain | Severe | Minimal |
| Mucosal involvement | Mild | Severe |
| Lesional pattern | Diffuse erythema, desquamation | Annular and targetoid lesions |
| Skin histology | Few inflammatory cells | Numerous inflammatory cells |
| Prognosis | Poor | Excellent |
4. How do you treat TEN?
Patients with TEN should be treated as burn patients, with supportive care to maintain fluid balance, avoid infection, and prevent adult respiratory distress syndrome (ARDS). In essence, TEN patients should be treated as severe burn victims. There are in vitro data to suggest that this entity may be the result of direct toxicity of drugs, or their metabolites, to skin cells. Anecdotal reports suggest that systemic corticosteroids are actually detrimental to TEN patients, although others continue to advocate their use. Initial anecdotal reports suggested that intravenous immunoglobulin therapy improved survival; however, this is controversial because other reports have not demonstrated efficacy.
5. How do you treat Stevens-Johnson syndrome?
Stevens-Johnson syndrome appears to be immunologically mediated and responds to systemic corticosteroids. Patients with severe symptoms, especially involvement of the oral mucosa, which interferes with eating and fluid intake, may be treated with a short trial of systemic corticosteroids. Stevens-Johnson syndrome is usually a self-limited disease with a 3-week course, and milder cases may not require systemic corticosteroids. Some authorities consider the use of systemic corticosteroids in this condition as controversial, because there are no good prospective, controlled studies evaluating this treatment. Therefore, an empirical 3- to 4-day trial of high-dose systemic steroids should be considered. If there is no clinical improvement at that time, the treatment should be discontinued.
6. What is pemphigus vulgaris?
Pemphigus vulgaris is a superficial blistering disease that typically affects middle-aged individuals (Fig. 64-2). It often presents initially with mouth ulcerations (60% of cases) but can involve blistering on areas above the waist. Pemphigus vulgaris may present acutely and, in severe cases, may resemble TEN or Stevens-Johnson syndrome. Early diagnosis is important because this condition is usually fatal if untreated, and current therapies are effective.
Figure 64-2. Pemphigus vulgaris demonstrating erosive lesions of the lips and left cheek.
(Courtesy of James E. Fitzpatrick, MD.)
Groves RW: Pemphigus: a brief review, Clin Med 9: 371–375, 2009.
7. Describe Nikolsky’s sign and its relationship to pemphigus vulgaris.
Pemphigus vulgaris involves only the upper layers of the epidermis; therefore, the blisters are very fragile, and typically patients present with only superficial ulcerations. Because of the fragility of the skin, one can apply lateral pressure with a finger to the intact skin around a lesion, causing the upper layer of the skin to become detached. This is called the Nikolsky’s sign, and it occurs in pemphigus and other superficial blistering diseases. This clinical sign can be helpful in differentiating superficial from deeper blistering diseases (e.g., bullous pemphigoid, bullous lupus erythematosus), in which Nikolsky’s sign is usually absent.
8. How is pemphigus vulgaris treated?
Therapy is designed to decrease the production of the antidesmosomal antibodies or to reduce the inflammatory response. Because pemphigus can be deadly, corticosteroids in high doses are used initially, despite their serious side effects. Prednisone is given in daily oral doses of 120 mg as an initial dose, which is then adjusted lower or higher depending on the patient response. Other immunosuppressive drugs, such as azathioprine and cyclophosphamide, have been used in conjunction with corticosteroids because of their steroid-sparing effect.
9. What is the DRESS syndrome?
DRESS stands for drug rash with eosinophilia and systemic symptoms, and it is a life-threatening reaction. It is characterized by a papulosquamous eruption, fever, enlarged lymph nodes, leukocytosis with eosinophilia, and liver or kidney involvement. Typical drugs that induce this reaction include anticonvulsants, allopurinol, and other sulfa drugs. The syndrome develops several weeks after drug initiation and can persist and recur for prolonged periods after the drug has been stopped. Therapy includes high-dose steroids and cyclophosphamide.
10. Are any dermatologic emergencies infectious in origin?
Yes. These are most commonly bacterial (e.g., necrotizing fasciitis, tularemia, meningococcemia, subacute and acute bacterial endocarditis) but also include viral infections (e.g., hemorrhagic fevers, neonatal herpes simplex infection), rickettsial infections (e.g., Rocky Mountain spotted fever), and fungal infections (e.g., mucormycosis).
11. Can emergent infections be differentiated by their cutaneous presentations?
Yes, although few cutaneous findings in emergent infections are pathognomonic. Infections that involve the skin can be organized generally by the appearance of the primary lesion (Table 64-2). Major cutaneous patterns of presentation include
12. What is the differential to consider in hemorrhagic lesions other than infection?
• Coagulation abnormalities, such as idiopathic thrombocytopenia, disseminated intravascular coagulation, and clotting factor deficiencies
13. What causes necrotizing fasciitis?
Purpura Fulminans (Purpura Secondary to Disseminated Intravascular Coagulation)
Necrotizing fasciitis has been well described for years but has recently received much attention in the lay press as the “flesh-eating bacteria.” It is a bacterial infection that is rapidly progressive, often over hours, destroying muscle and subcutaneous tissues. Death or loss of a limb may occur, if it is not diagnosed and treated early in its course. It is most commonly associated with β-hemolytic streptococci but may also be due to other gram-positive or gram-negative organisms, or it may be polymicrobial.
Violaceous Skin Discoloration
Table 64-2. Diagnostic Signs in Dermatologic Infectious Emergencies
| Petechial/Palpable Purpura |
14. Describe the clinical presentation of necrotizing fasciitis.
The bacteria usually enter through a surgical or traumatic wound and quickly move along fascial planes destroying vessels and tissue. Within the first 48 hours, the involved area that is initially erythematous, indurated, and painful becomes a dusky blue, indicating lack of circulation in the area (Fig. 64-4). Because there is significant vessel thrombosis, a biopsy usually results in little or no bleeding, and this is a useful diagnostic sign if present. Surgical debridement in addition to systemic antibiotics is necessary and often reveals extensive covert tissue necrosis.
15. Can other cutaneous infections look like necrotizing fasciitis?
Actually, necrotizing fasciitis is a type of infectious gangrene or cellulitis that rapidly progresses to destroy skin, subcutaneous tissue, and muscle. There are other types of gangrene, all of which have cutaneous findings similar to those of necrotizing fasciitis:
• Staphylococcus aureus and, occasionally, gram-negative organisms can cause progressive bacterial synergistic gangrene. This disease presents with a dusky erythematous discoloration of the skin followed by deep ulceration.
• In gas gangrene or clostridial gangrene, caused by the anaerobe Clostridium perfringens, patients typically present after a penetrating or crush wound with a tender, painful, edematous, white area that often becomes bronze with cutaneous blistering. Occasionally, when one palpates the area, crepitation or a crackling sensation is noted secondary to gas formation in the tissue. As with necrotizing fasciitis, timely diagnosis and treatment are necessary to minimize morbidity and mortality.
16. Are there any parasitic disease “emergencies” that have cutaneous manifestations?
Trichinosis is caused by the small parasitic worm Trichinella spiralis, which is ingested in inadequately cooked meat containing its cysts. Common sources of encysted meat include bears and other carnivores or omnivores. Ingestion of pork, once a common source of trichinosis, is an extremely rare source today. The cutaneous signs include a macular or petechial eruption, splinter hemorrhages, periorbital edema, and conjunctivitis. The systemic signs and symptoms begin 1 to 4 weeks after ingestion and consist of eosinophilia, fever, headache, myalgias, and brain hemorrhage, which can lead to death.
17. Are there any other parasitic disease emergencies?
Yes. Another is cysticercosis cutis, which is a cestoidal infection due to the larval form of the pork tapeworm, Taenia solium. Typically, Taenia eggs enter the stomach from the intestine via reverse peristalsis, and they develop into oncospheres that penetrate the stomach wall and enter the circulation. They become lodged in internal organs, such as the heart, brain, muscles, lungs, and eye. They also move to the subcutaneous tissues and develop into cysts that contain cysticercus larvae. They are usually numerous and can become calcified as evidenced by x-ray. With the presentation of multiple subcutaneous cysts in a patient with unexplained neurologic signs or symptoms, one must keep this diagnosis in mind.
18. Do mycobacterial infections cause any dermatologic emergencies?
Most mycobacterial infections are relatively chronic and do not constitute emergencies. However, when patients with Hansen’s disease (leprosy) are treated, they may undergo a “reversal reaction” that is secondary to a change in their immune status, resulting in acute inflammation of the involved areas. This may produce mild erythema and swelling of the skin and subcutaneous tissue. The apparent benignity of the situation belies its seriousness. The involved nerves are completely destroyed, resulting in permanent motor and sensory damage to the area. The lack of sensory input and resultant trauma over years lead to severe disfigurement of the extremities. Treatment consists of high-dose prednisone tapered over weeks.
20. What are the cutaneous findings in acute and bullous SLE?
The cutaneous findings of acute SLE are most common on the sun-exposed areas of the skin. The eruption consists of an evanescent erythema that is especially evident over the malar area of the face, producing the characteristic “butterfly rash.” The erythema lasts hours to days and can resolve without residua. In a significant number of patients, the acute erythema can evolve into discoid lupus erythematosus, which is a chronic scaling eruption with scarring.
21. How does neonatal lupus erythematosus (NLE) present?
It is an acute self-limited disease that gradually improves over 1 to 2 months. The cutaneous findings include diffuse superficial erythema and scaling that are often most apparent in the malar area of the face but can occur anywhere. Neonates frequently have other systemic findings, such as those seen in SLE: anemia, thrombocytopenia, jaundice, and hepatosplenomegaly with abnormal liver function tests. Another prevalent finding is atrioventricular heart block, which is permanent.
22. Why are prompt recognition and treatment of NLE important?
Frequently, NLE eruptions are misdiagnosed as infectious in origin. This subjects the infant to the unnecessary risks of systemic antibiotics, while the presence of heart block may be missed, and appropriate systemic treatment (steroids) for the other NLE problems is delayed.
Key Points: Dermatologic Emergencies
1. Dermatologic emergencies do exist, and some, such as toxic epidermal necrolysis and necrotizing fasciitis, have characteristic skin signs.
2. Recognition of specific skin signs and the early diagnosis of emergent skin disorders can be lifesaving.
23. Why is dermatomyositis considered an emergency?
Dermatomyositis can develop rapidly with significant mortality. Skin findings in this disease can predate significant muscle involvement and be quite helpful in early diagnosis and treatment, especially in children. The skin findings that are helpful in diagnosis are
24. What is leukocytoclastic vasculitis?
This term is histologically descriptive of a group of diseases that cause acute neutrophilic inflammation and damage to the small vessels of the dermis. This damage can occur without apparent underlying etiology or as a cutaneous manifestation of a systemic disease, such as Henoch-Schönlein purpura, SLE, or cryoglobulinemia. The eruption typically consists of “palpable purpura,” varying in size from a few millimeters to several centimeters, mainly on the lower extremities. The cutaneous lesions of this group of diseases usually resolve without sequelae, but the internal organ involvement can be severe. The differential diagnosis of leukocytoclastic vasculitis should include infections that cause palpable purpura, such as meningococcemia.
25. What are the skin signs of Still’s disease?
The diagnosis of Still’s disease (juvenile rheumatoid arthritis) can be perplexing because a significant number of these patients (25% to 30%) do not present with arthritis but with an evanescent eruption, spiking fever, leukocytosis, lymphadenopathy, and splenomegaly. The disease can be rapidly progressive, with severe bone and joint destruction and growth retardation. The rash, which occurs in 25% to 40% of patients, can be present for months to years before the arthritis. The eruption is typically but not always fleeting, lasting up to 24 hours, and usually occurs in conjunction with fever. The rash may be diffuse with truncal accentuation and consists of coral-salmon red, flat macules to slightly elevated papules. Treatment for this disease usually consists of locally injected or systemic steroids. Other immunosuppressive drugs have also been used successfully.
Inflammatory cutaneous disorders
26. Why is pyoderma gangrenosum a dermatologic emergency?
Pyoderma gangrenosum is one of a group of inflammatory skin diseases called neutrophilic dermatoses because, histologically, they have dermal infiltrates of neutrophils. It is a dermatologic emergency because it is often rapidly progressive, causing severe local tissue destruction. Pyoderma gangrenosum is frequently misdiagnosed as an infectious process or a brown recluse spider bite and is then treated by debridement. However, surgical procedures or any mechanical manipulation of acute lesions induces progression of disease to the normal surrounding skin, enlargement of the lesion, and further tissue destruction. Therefore, it is imperative to recognize and treat these lesions correctly early to avoid massive tissue destruction and loss.
27. How does pyoderma gangrenosum present?
Clinically, the lesions begin as a small papule/pustule that enlarges to form an ulcer. The ulcer has a necrotic center that typically involves the skin and subcutaneous tissues down to muscle, tendons, and fascia (Fig. 64-5). In older lesions, the intact epidermis at the borders of the lesion is erythematous with a purple hue and has a characteristic undermined edge. Another helpful clinical feature is the extreme pain and tenderness of these lesions. There are few cutaneous diseases that approach pyoderma gangrenosum in the severity of lesional pain and tenderness.
28. Under what circumstances do childhood vascular anomalies become dermatologic emergencies?
The most common vascular anomalies (about 3% of births) that have the potential to become dermatologic emergencies are infantile capillary hemangiomas. These lesions can be present at birth (approximately 20%) but more often develop over the first several weeks of life. Infantile hemangiomas have a rapid growth phase, during which they rapidly enlarge, and then they regress.
Most commonly, these tumors are only a cosmetic problem, but if they occur around the eyes or in the oral cavity (Fig. 64-6), they can cause significant morbidity and mortality. Some ophthalmologists suggest that even a few days of obstructed vision in a newborn can inhibit normal visual development. Therefore, an infantile hemangioma that may block an infant’s visual fields should be treated aggressively. Likewise, enlarging infantile hemangiomas of the upper respiratory tract and oral cavity can result in acute emergent situations and must be treated early in their course. In rare cases, large hemangiomas can also produce high-output cardiac failure.
29. How are hemangiomas treated?
Hemangiomas can be treated with intralesional steroids, but in lesions involving the facial area, this treatment should be avoided because there have been reports of steroid suspension embolism of the central nervous system (CNS) and retinal vessels. In these cases, systemic steroids should be utilized. Recombinant interferon-α and porpranolol have also been used to treat infantile hemangiomas that have not responded to corticosteroid therapy. Rarely, large, rapidly growing hemangiomas have been associated with platelet trapping and acute thrombocytopenia.
30. Is acne fulminans a dermatologic emergency?
Although acne is not usually considered an emergency, this condition, if not treated acutely, can lead to severe cutaneous scarring and its attendant psychological problems. This type of acne usually occurs in teenage males, but there are cases reported in females. The eruption is characterized by rapid suppuration of large, highly inflamed nodules and plaques, resulting in ragged ulcerations and scarring of the chest, back, and, less commonly, face. Often attendant with the cutaneous symptoms are fever, leukocytosis, arthralgias, and myalgias, suggesting a systemic upregulation of the immune system.
31. What is the treatment for acne fulminans?
The treatment for this condition is high-dose oral steroids (e.g., prednisone) and early institution of oral retinoids such as 13-cis-retinoic acid. Paradoxically, oral retinoic acid can also induce acne fulminans in the first month of treatment. Physicians who use this medication should be aware of this potential side effect.
32. Are there drug eruptions that are dermatologic emergencies?
Most drug eruptions are relatively benign and consist of a morbilliform or macular erythema that occurs without other signs or symptoms. On occasion, drug eruptions can present as diffuse exfoliative erythroderma, or red man syndrome. In these cases, patients develop a total body erythroderma with pruritus and scaling. In addition to drugs, other causes of exfoliative erythroderma that must be ruled out include psoriasis, lymphoma, and flares of seborrheic or atopic dermatitis. Other types of drug eruptions that can be dermatologic emergencies include toxic epidermal necrolysis, leukocytoclastic vasculitis, and severe urticaria or angioedema.
35. Is heatstroke considered a dermatologic emergency?
Although heatstroke is not typically considered a “dermatologic problem,” it does have characteristic skin findings that are helpful in making a quick diagnosis. In a heatstroke victim, the skin is erythematous, hot, and dry. These findings in association with unconsciousness should alert one to the diagnosis. Therapy needs to be instituted promptly to prevent death or severe CNS damage.
36. What are the cutaneous signs of child abuse?
Because child abuse can lead to acute morbidity and mortality, its recognition should be of paramount importance when evaluating pediatric patients. Cutaneous signs of abuse include:
• Bruising and abrasions: These lesions are usually present in patterns or in areas not consistent with the history or trauma from common childhood accidents (Fig. 64-7).
• Burns with unusual patterns: Some examples are cigarette burns that appear randomly over the body or dunking scald injuries, which have distinct borders and, occasionally, have a “doughnut” pattern around the buttock area when the buttock is pressed against the cooler tub surface.
37. What are the skin signs of a lightning strike?
Lightning strike patients often have very characteristic skin findings. In addition to entry and exit burn wounds, the skin of these patients can often exhibit a swirled or fernlike erythema of the involved area (Fig. 64-8). If there is any doubt of the etiology, the biopsy findings in the skin are pathognomonic. It is important to diagnose this injury, because significant covert injury to the underlying fascia and muscles can occur. The degree of damage must be assessed and the patient treated for arrhythmias, shock, fluid and electrolyte imbalances, peripheral and central neural damage, and covert tissue damage to optimize recovery.
38. What is scleredema neonatorum?
It is typically seen in newborns but has been reported in infants up to 3 months of age. Clinically, it presents as a hardening of the skin with decreased temperature, vascular mottling, and a yellow-white discoloration in a symmetrical distribution, usually over the thighs and trunk. It usually occurs in the setting of an underlying severe illness and is associated with a 50% mortality rate.
39. What are the cutaneous findings in cholesterol emboli?
Cholesterol emboli can present anywhere in the body, but cutaneous manifestations most commonly occur on the lower extremities. This condition can occur spontaneously, but often cholesterol emboli to the skin present after angiography when trauma to aortic plaques dislodges cholesterol into the circulation. Clinically, the patient presents acutely with fairly well-demarcated areas of cyanosis or livedo reticularis on the feet and lower legs as a result of emboli blocking arterial circulation. These areas can undergo necrotic changes, resulting in painful ulcers.
40. How are cholesterol emboli diagnosed?
Cholesterol crystals within the lumina of the vessels on biopsy are diagnostic. The skin biopsy should ideally be an excision, and step sections should be examined because the atheromatous emboli are often focal. It is helpful to auscultate carefully over the major vessels of the abdomen and lower extremities after the patient has exercised to increase the pulse rate. This presentation is important because patients often have involvement of other organ systems, especially the kidneys. Further angiographic studies should be limited and treatment of the underlying hyperlipidemia initiated.
Manganoni AM, Venturini M, Scolari F, et al: The importance of skin biopsy in the diverse clinical manifestations of cholesterol embolism, Br J Dermatol 150:1230–1231, 2004.
