Necrolytic acral erythema (NAE) is characterized by erythema, blisters or erosion in the acute stage to well-defined, hyperkeratotic plaques on the dorsum of feet and toes in the chronic stage [ 1 ] . We present a dermoscopy of a case of NAE which may help in the diagnosis.
A 32-year-old female presented with hyperpigmented plaques on the dorsum of her feet, predominantly on the medial aspect ( Figure 1A ). Erythematous macules, plaques of irregular shape and size varying from 0.5 cm 2 to 4 cm 2 in diameter were present on bilateral lower legs interspersed with follicular or non-follicular pustules, erosions and ulcers superimposed with yellowish crust ( Figure 1B ). Differential diagnosis of allergic contact dermatitis, psoriasis, pellagra and necrolytic acral erythema was kept. Dermoscopic examination (Illuco IDS 1100, 10x magnification, polarized mode) of the acute lesions revealed multiple perifollicular white globules on intense red-violaceous background interspersed with short linear vessels ( Figure 2A ). Dermoscopy of the ulcer showed yellow globules with radial white striations surrounded by brown dots and patches in polarized mode and dirty yellow scales and white globules in non-polarized mode ( Figure 2, B and C ). Raw areas revealed uniformly distributed red dots and globules with peripheral white scales in polarized dermoscopy ( Figure 2, D and E ). Dermoscopy of chronic hyperkeratotic hyperpigmented plaques presented a mixture of gray-brown pigmentation along with dirty white scales and red globules ( Figure 2F ). Few resolved areas reveal whitish striations in a branching pattern with brown patches and linear red vessels on a white background ( Figure 2, G and H ).
Her viral markers were non-reactive and patch test with Indian standard and footwear series was negative. However, serum albumin and serum zinc level were borderline low. Skin biopsy from the hyperkeratotic plaque revealed psoriasiform dermatitis ( Figure 2I ). She was prescribed a tablet zinc acetate 100 mg three times a day for 3 months to which the erythematous lesions, ulceration and edema responded well in 2 weeks. Topical super potent steroid was given for the hyperkeratotic lesions. There is no relapse at 3 months follow-up ( Figure 2J ). The clinical, dermoscopic and histopathologic findings along with supportive investigations and substantial improvement with oral zinc supplementation confirmed our diagnosis of NAE.
Although NAE has been associated with HCV infection, there have been few HCV seronegative case reports [ 2 , 3 ] . Our patient was also seronegative for HCV infection. Clinically, patients with NAE are systemically well and have a typical acral distribution which helps in ruling out causes of other acral erythemas such as pellagra, biotin and fatty acid deficiency [ 1 ] . Chronic lesions of NAE have to be differentiated from psoriasis, hyperkeratotic eczema and hypertrophic lichen planus. Our findings of dermoscopy of the lesions may assist in diagnosing both acute and chronic manifestations of NAE ( Table 1 ). We could find only a single study on dermoscopy of necrolytic acral erythema [ 1 ] .
One should have a good suspicion of NAE even if the patient is seronegative for HCV and has innocuous-appearing psoriasiform or eczematous lesions with normal serum zinc levels. Dermoscopy may be of great assistance for the same, however, more studies on dermoscopic findings of this disease need to be done.
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