INTRODUCTION
A 59-year-old African American male presented with a
widespread pruritic skin eruption that had been present
for 1 year. His past medical history was significant for
chronic hepatitis C (HCV) infection with cirrhosis, and he was undergoing
evaluation for liver transplantation. Physical examination
revealed hyperpigmented erythematous to violaceous scaly
plaques on the bilateral legs in an extensor distribution, dorsal
feet, dorsal arms and hands, as well as on the abdomen (Figures
1 and 2). Histopathology of a skin biopsy showed mild epidermal
acanthosis with parakeratosis, rare midepidermal necrotic
keratinocytes, and a perivascular lymphocytic infiltrate (Figure
3). Based on these findings and the clinical scenario, the diagnosis
of necrolytic acral erythema (NAE) was made, and the patient
was started empirically on 220 mg of zinc sulfate per day.
DISCUSSION
Necrolytic acral erythema was first described in 1996 in Egypt
as a subtype of necrolytic erythema associated with HCV; the
incidence approaches 1.7% of patients with HCV.1-3 Clinically,
NAE presents with well-demarcated scaling erythematous
papules and plaques with secondary lichenification and later
hyperpigmentation.3 Histologically, NAE is characterized by
acanthosis, hyperkeratosis, necrosis of keratinocytes, and
perivascular infiltrate of lymphocytes. Pathological findings
may vary with the stage of disease.
The pathophysiology of NAE with respect to HCV is unclear.
Evidence suggests an association with HLA-DRB1, complement
factors, and both antismooth muscle and antinuclear
antibodies.4 There have also been data to support a correlation
between viral load and specific viral genotypes and NAE.5 It is
unclear if the presence of NAE relates to HCV prognosis.
Low levels of zinc have been reported in several cases of
NAE, and zinc sulfate therapy has been reported to clear lesions
in some patients, regardless of normal or abnormal
zinc levels.6,7 Other cases have reported clearance of the
lesions with interferon and ribavirin-induced virologic suppression.
8,9 The variable response to treatment supports a
multifactorial pathophysiology.
Necrolytic acral erythema is uniquely associated with HCV. In
our patient, treatment was provided empirically with zinc sulfate.
The patient has yet to return to this clinic for evaluation of
clearance of NAE lesions.