Norwegian scabies mimicking rupioid psoriasis

Abstract

Norwegian scabies is a highly contagious skin infestation caused by an ectoparasite, Scarcoptes scabiei var. Hominis, which mainly affects immunosuppressed individuals. Clinically, it may simulate various dermatoses such as psoriasis, Darier's disease, seborrheic dermatitis, among others. This is a case report of a 33-year-old woman, immunocompetent, diagnosed with generalized anxiety disorder (cancer phobia), who had erythematous, well-defined plaques, covered with rupioid crusts, on her neck, axillary folds, breast, periumbilical region, groin area, besides upper back and elbows, mimicking an extremely rare variant of psoriasis, denominated rupioid psoriasis.

Norwegian scabies - rare case of atypical manifestation

“…Another significant procedure is differential diagnosis with other dermatoses, such as crusted psoriasis - a rare form of the disease manifested by erythematous plaques covered with scabs, 3,8 similar to the patient in this case.…”

“…7,8 Scratching is important because it destroys the burrows of the mites, which did not occur with the patient in this case report.…”

“…Therefore, a prolonged treatment with systemic scabicides is recommended, paying special attention to occacional concomitant infections. 4,5,8 The most common treatment for crusted scabies is a single or recurrent dose of ivermectin (oral), depending on the severity of the case, as with the patient in this case. 2 However, some pesticides and scabicides such as lindane might be applied.…”

Erythroderma due to iatrogenic immunosuppression: a case of Norwegian scabies

“…Treatment is challenging due to the heavy load of mites on the body as well as the presence of thick plaques. Treatment consists of the application of keratolytic agents to diminish the hyperkeratotic plaques and requires repeated oral ivermectin administration with multiple applications of topical scabicidal agents such as permethrin 5% [10].…”

An Elderly Long-Term Care Resident with Crusted Scabies

“…Despite the higher mite load of crusted scabies, some patients do not experience an increase in pruritus above baseline ( 4 ). The plaque appearance of crusted scabies can be mistaken for psoriasis, potentially leading to a delay in diagnosis ( 5 – 7 ).…”