A 10-year-old girl has multiple excoriations that have appeared on the skin of her hands over the past week. The child reports that she scratches her hands because they itch. Physical examination shows multiple 0.2- to 0.6-cm linear streaks in the interdigital regions. Treatment with a topical lindane lotion resolves the condition. Which of the following organisms is most likely responsible for these findings?
High-Yield Explanation
The small scabies mites burrow through the stratum corneum to produce the linear lesions, and the mites along with their eggs and feces produce intense pruritus. Scabies is easily transmitted by contact and typically occurs in community outbreaks. Ixodes scapularis is the tick that is the vector for Borrelia burgdorferi organisms, which cause Lyme disease and erythema chronicum migrans. Molluscum contagiosum is caused by a poxvirus that produces a localized, firm nodule. The erythematous macules and pustules of impetigo in children are often caused by staphylococcal and group A streptococcal infection. Tinea corporis is a superficial dermatophytic fungal infection that can produce erythema and crusting.