Scabies presenting with bullous pemphigoid-like lesions

Abstract

A wide range of clinical manifestations may be seen in scabies, from classic pruritic papules and burrows to secondary features such as impetigo. Bullus lesions are a less frequent. Twenty cases of scabies presenting with bullae have been reported so far in the medical literature. Differentiating this subtype of scabies from the immunobullous disease bullus pemphigoid is a diagnostic challenge. A 42-year-old man was referred to our dermatology outpatient clinic with 3-month history of severe pruritus and tense blisters affecting mainly the lower trunk, arms and legs. An initial biopsy was suggestive for bullous pemphigoid. Close physical examination revealed small excoriated papules and a few burrows on borders of the hands and wrists. Skin scraping of the lesions on wrists was positive for Sarcoptes scabiei. Another biopsy specimen from a recent blister revealed subepidermal bullae with fibrin and inflammatory cells, particularly eosinophils. Direct immunofluorescence exam was negative. The patient was treated with lindane lotion followed by crotamiton cream with near complete resolution of the lesions. Scabies must be considered in patients presenting with recent onset of unexplained pruritic bullous lesions. Biopsy and immunofluorescence studies together with skin scrapings for Sarcoptes scabiei could help to differentiate these cases from bullous pemphigoid. Antiscabietic treatment results in resolution of bullous lesions in the affected patients.