SkIndia Quiz 21: Recurrent papulonodular lesions on elbows, fingers and lower leg

d A 35-year-old human immunodeficiency virus (HIV)-negative female patient presented with smooth surfaced umbilicated papulo-nodules of variable sizes of 3 years duration. The lesions were distributed over the extensor aspects of elbows, knuckles, dorsum of fingers and over medial malleolus of left leg [Figure 1]. They progressively increased in size to attain the present status. The lesions were asymptomatic but she complained of occasional sensation of numbness and pain over the fingers; in winter season as well as, on exposure to cold water. The lesions over the right elbow showed evidence of ulceration. She did not complain of any joint pain and had no ocular complaints, sore throat, fever or any constitutional symptoms. Fingernails showed features consistent with distal lateral subungual onychomycosis. There was no history of skin tightening or malar rash. There was neither any sensory loss nor history of similar lesions elsewhere. Past history revealed the occurence of similar lesions many years ago, which responded to pharmacotherapy with dapsone. The lesions used to resolve with atrophic scarring, without any pigmentation. Family history was non-contributory. Systemic examination was unremarkable. Laboratory investigations showed a high absolute eosinophil count of 11,500, with the rest of the hemogram being normal. Urea, creatinine, urinalysis, serum calcium (9.7 g/dl), uric acid (3.2 mg/dl) were all within the normal range. However, alkaline phosphatase (250 IU/L) and serum lactate dehydrogenase (766 IU/L) were raised. Anti-nuclear antibody, anti-neutrophil cytoplasmic antibody, anti-scl 70 antibody, anti-streptolysin O titers, venereal disease research laboratory test, C-reactive protein, rheumatoid factor, slit-skin smear examination, Mantoux test and chest X-ray, were normal. Ultrasonography of abdomen and color doppler of the arterial system of the upper limbs were normal. Bone marrow examination showed eosinophilic myelocyte and metamyelocyte, increased mature eosinophils with blasts lesser than 5% and mild megaloblastoid changes. Histopathology of a nodular lesion showed leukocytoclastic vasculitis and fibrinoid degeneration and neutrophilic infiltrate and fibrosis in the dermis [Figure 2].