Background: Necrolytic acral erythema (NAE) is a distinctive skin lesion that was first described in 1996 with only few cases being reported, mostly from Egypt. It is unique in its acral distribution and exclusive association with hepatitis C virus (HCV) infection.
Methods: Twenty-three patients (mean age 41.7 +/- 11.5 years; M:F 10:13) with clinical features consistent with NAE were enrolled in a 3-year period. Five of those were known HCV-infected individuals and 18 were referred by the dermatologist for evaluation and HCV screening. Liver function tests, serum zinc, hepatitis B markers, HCV antibodies and HCV-RNA were tested. All patients were subjected to skin biopsy examination; five lesional biopsies were selected for electron microscopic examination and capillary endothelium was scanned for hepatitis C viral particles. An additional five patients were subjected to detection of HCV-RNA in their skin biopsies by polymerase chain reaction. All patients received oral zinc sulfate supplementation while interferon-alpha therapy combined with ribavirin was available for four patients.
Results: Most NAE patients were adults (91.3%) and the skin lesions were predominantly chronic (78.3%), with affection of the dorsa of toes and/or feet in all cases. Skin biopsies showed hyperkeratosis, psoriasiform epidermis and upper epidermal necrosis. Electron microscope examination demonstrated clumped tonofilaments in the keratinocytes, yet HCV-RNA could not be detected in the skin lesions of examined cases. Interferon-alpha combined with ribavirin caused regression of skin lesions in three patients and complete clearance in one patient. Some improvement was induced by oral zinc administration.
Conclusion: Necrolytic acral erythema is considered to be a cutaneous marker for HCV infection. The majority of patients are diagnosed by dermatologists. Therefore, improved awareness of this cutaneous lesion should prompt early diagnosis and treatment of HCV, which should in turn cure the lesion and prevent progression of liver disease.