At his first well-child visit after a family move, an 8-year-old boy was noted to have bilateral erythematous plaques on the surfaces of his hands and feet. Mother reported that the condition had been present since he was 2 or 3 months old. Patient's father and other male relatives on the paternal side (uncles, grandfather, great-grandfather) were similarly affected. No other associated symptoms, such as hyperhidrosis, reported. The child did not have a history of eczema, asthma, or food allergies; however, he did have a history of allergic rhinitis and occasional pruritus.
Patient was healthy and otherwise appeared well. Weight, 24.2 kg (50th percentile); height, 130 cm (50th percentile). Blood pressure was 93/67 mm Hg; other vital signs normal. No lesions noted in the mouth or on teeth or gums. Heart and lungs were normal; no organomegaly or hemihypertrophy.
Examination of the skin revealed a raised clear line of demarcation between the unaffected skin of the ankles and wrists and the thickened, red skin on his palms and soles. The soles of his feet were characterized by itchy red papules; a scaly, thickened appearance; and several raw, deep fissures resulting from a recurrent pyogenic skin infection from which he had recently recovered after treatment with clindamycin(Drug information on clindamycin). His toenails were slightly discolored and dystrophic, but he did not appear to have a fungal infection.
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