A necrotic area in a patient with calciphylaxis.
This page deals with the patient who presents with one or more large necrotic lesions. Different from this is the patient with palpable purpura. The two broad categories causing necrosis of the skin are infection and vasculitis.
For the acutely-ill patient with necrotic skin lesions, it is important to exclude septic emboli (e.g. Neisseria, Staph, RMSF, Strep, Pseudomonas, Candida). A skin biopsy (usually punch) with special stains for bacteria, fungi and AFB is in order. Sending another skin specimen for bacterial, fungal and AFB culture should also be done. One may aspirate tissue fluid from an early lesion for gram stain and culture.
Typical blood work for patients with necrotic skin lesions may include CBC with peripheral eosinophil count (Churg-strauss syndrome), creatinine, LFT's, RF, ASO, ANA, ANCA, SPEP (Hypergammaglobulinemic purpura), Hepatitis B and C, ELISA for parvovirus B19, complement levels, cryoglobulins, antiphospholipid antibody, anti-neutrophil cytoplasmic antibody, PT, PTT, protein C, protein S, cryoglobulins, fibrin split products, anti C1Q antibody and IgA-fibronectin aggregates (if available).
Other potential laboratory studies include CXR, stool guiac and urine analysis,
For patients with chronic renal failure on dialysis include parathyroid hormone, phosphorus, and calcium (rule out calciphylaxis).
Aspergillosis, primary cutaneous
Brown recluse spider bite
Fluoroscopy-Induced Skin necrosis (AD 2003;139;140)
Calcium chloride, cutaneous contact
Coma, sweat gland necrosis
Purpura fulminans - Disseminated Intravascular Coagulation
Infections, various, e.g. fungal.
Necrotizing fasciitis. Warm induration of a portion of a limb followed by dusky or violaceous discoloration, then bulla formation and necrosis is characteristic.
Streptococcal toxic shock-like syndrome
Vasculitis (any): Photograph courtesy Michael O. Murphy, MD
Endothelial dysfunction thrombosis in hiv positive patients may be caused by increased antiphospholipid antibodies and decreased protein s as part of general endothelial cell dysfunction. J of aids 1992;5;484
Digital infarcts occurred in two HIV-1-infected patients with CMV viremia.