Genital nodular scabies in Indonesian adolescent boy

Abstract

<p class="abstract">Scabies is an infection caused by infestation and sensitization to the parasitic mite <em>Sarcoptes</em> <em>scabiei</em> <em>var</em>. <em>hominis</em>. World Health Organization (WHO) in 2017 declared that scabies was included as Neglected Tropical Diseases (NTD) and become a significant health concern in many developing countries. According to the Global Burden of Disease Study in 2015, Indonesia was the first place among 195 countries with the greatest scabies burden. Nodular scabies is an uncommon clinical variant in classical scabies cases, characterized by persistent pruritic nodules due to immune response against the mites and their products (eggs and scybala). This variant was occurring in about 7% of scabies patients. The incidence and prevalence of nodular scabies are still unknown. Nodular scabies is usually found in young children and affect the male genitalia, especially in the scrotum. The diagnosis of nodular scabies generally can be made clinically and supported by a history of receiving adequate anti-scabies treatment. Active infestation form or atypical manifestations of nodular scabies might be confused the diagnosis. Diagnostic tools such as dermoscopic and skin biopsy may aid in differentiating them. Histopathology features also can rule out the differential diagnosis. Corticosteroid (topical or injection) and topical inhibitor calcineurin (tacrolimus) was reported effective in treating nodular scabies. We reported an Indonesian adolescent boy who has been diagnosed with scabies complained of persistent pruritic nodules on his genital for several months despite adequate anti scabies therapy being given. Intralesional corticosteroid injection was the options treatment of this case due to the nodular lesion being resistant with topical corticosteroids, while topical tacrolimus is difficult to obtain in our region.</p>