Calciphylaxis - Anogenital in
Calciphylaxis is increasing in incidence and is most commonly associated with chronic renal failure, hemodialysis, and secondary hyperparathyroidism. According to one study, patients with penile calciphylaxis are more likely to have end-stage renal disease, hyperparathyroidism, and normal body mass index compared to nonpenile calciphylaxis patients. There are also many cases of "nonuremic" or "nontraditional" calciphylaxis, which can occur in the setting of liver disease, diabetes, warfarin use, use of calcium-based phosphate binders, systemic corticosteroid use, solid organ malignancies, systemic lupus erythematosus, and Crohn disease. Other risk factors include female sex, obesity, Northern European descent, and hypoalbuminemia.
Notably, warfarin-associated nonuremic calciphylaxis tends to occur about 2.5 years after warfarin initiation on the lower extremities, does not have associated calcium abnormalities, and appears to have a more favorable prognosis than calciphylaxis associated with renal failure states.
Early lesions are extremely painful, violaceous, retiform patches and plaques, classically on fat-bearing areas such as the thighs, buttocks, and abdomen. This is followed by necrosis, ulcers, eschar formation, and possibly gangrene. Induration of the surrounding tissues may be present. Lesions have been reported to be triggered by local trauma, including from insulin or heparin injections, or a skin biopsy. Most lesions develop over the course of weeks to months, while some may progress more rapidly.
Mortality from calciphylaxis is high (60%-87%) and is largely secondary to sepsis from large, nonhealing ulcers. Mortality from penile calciphylaxis is estimated to be 64%, with average survival of 2.5 months, with 50% of mortality occurring at 3 months and 62.5% at 6 months, according to one study.
E83.59 – Other disorders of calcium metabolism
237900002 – Calciphylaxis
Differential Diagnosis & Pitfalls
- Fournier gangrene
- Necrotizing fasciitis
- Herpes simplex virus
- Disseminated intravascular coagulation
- Purpura fulminans
- Cryoglobulinemia – Favors extremities and acral areas where body temperatures are lower.
- Antiphospholipid syndrome
- Coumadin (warfarin)-induced necrosis – Differs from warfarin-induced nonuremic calciphylaxis. Warfarin-induced skin necrosis is caused by immediate hypercoagulable state from decreased protein C and S and typically occurs 3-10 days after warfarin initiation and is characterized by hemorrhagic bullae with retiform purpura, typically on the breasts, thighs, and buttocks, versus warfarin-associated calciphylaxis, which occurs months to years after warfarin initiation.
- Nephrogenic systemic fibrosis
- Pyoderma gangrenosum
- Cholesterol emboli
- Granulomatosis with polyangiitis
- Cocaine levamisole toxicity
- Hyperoxaluria – Oxalate deposition may cause similar deposition in vessels and is also associated with renal failure.
- Ecthyma gangrenosum – Begins as a painless macule or papule and is associated with gram-negative sepsis.
- Zoon balanitis
Drug Reaction Data