Crusted scabies in an immunocompetent patient: A case report and literature review
DOI:
https://doi.org/10.25251/a2wwdb85Keywords:
crusted scabies, immunocompetence, norwegian scabiesAbstract
Crusted (Norwegian) scabies is a rare, highly contagious form of scabies characterized by an extreme mite burden and the development of hyperkeratotic plaques. It typically occurs in individuals with compromised cell-mediated immunity. We present the case of a 34-year-old immunocompetent male with a 12-month history of generalized erythematous lesions. The lesions, which were initially pruritic and later became painful, began on the abdomen and progressed to form extensive hyperkeratotic crusts with areas of exudation and adherence to clothing.
Physical examination revealed involvement of approximately 90% of the total body surface area, featuring papules, pustules, and verrucous hyperkeratotic crusts, with a predilection for the dorsal hands, groin, and axillae. Direct microscopic examination of skin scales confirmed the presence of numerous Sarcoptes scabiei var. hominis mites.
Laboratory investigations demonstrated leukocytosis, eosinophilia, microcytosis, hypoalbuminemia, and an elevated erythrocyte sedimentation rate. Serological testing for human immunodeficiency virus (HIV), human T-lymphotropic virus (HTLV)-1/2, hepatitis B surface antigen, and syphilis returned negative results.
The patient was treated with oral ivermectin, topical 5% permethrin cream, and urea-based emollients, which resulted in a positive clinical response. He was discharged after three days with comprehensive instructions for environmental decontamination. This case underscores that crusted scabies can occur in the absence of demonstrable immunosuppression, highlights the critical role of diagnostic aids such as microscopy and dermoscopy, and reinforces the necessity of multi-dose ivermectin therapy combined topical scabicidal and keratolytic agents, supplemented by rigorous environmental control measures.
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Copyright (c) 2026 Juan Camilo Saldarriaga Giraldo, Maria del Pilar Marquez-Morón, Ana María Mejía Giraldo (Author)
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