Prevalence of scratching during examination among patients with scabies and among patients with other pruritic dermatoses.

Abstract

Scabies is a parasitic skin disease. Its clinical diagnosis may be challenging. In a prospective observational study, we enrolled all consecutive patients ≥16years of age with a presumptive diagnosis of scabies and all patients ≥16years of age with a diffuse itchy dermatosis lasting for more than 1week. We investigated whether patients with scabies were more prone to scratch themselves during the consultation than patients with other pruritic dermatoses. We observed that a significant proportion of patients (25/62, 40%) with scabies had to scratch while talking or being examined. This clinical sign was less frequently noticed in patients with pruritic dermatoses of other origins (26/196, 13%) (P<0.001). The observation of a patient scratching himself during the consultation should prompt serious consideration ofscabies. This easily observable clinical sign may be especially useful in low-resource settings, where scabies is known to be very prevalent.