An otherwise healthy 6-year-old Indian boy presented with a 3-day history of severe generalized pruritus with nocturnal aggravation of symptoms. His mother too had similar symptoms. On examination, multiple tiny erythematous excoriated papules were observed over bilateral finger webs, anti-cubital fossa, axilla. A distinct, partially deroofed curvilinear erythematous track (2.5 cm long) was observed over the preputial skin (Figure 1). What is the diagnosis?
Figure 1.
A partially deroofed curvilinear erythematous track over the preputial skin.
Diagnosis
The clinical findings of the patient are consistent with the diagnosis of scabies infestation with evidence of burrow shown in the picture.
Scabies is a contagious skin disease caused by the infestation of a mite, Sarcoptes scabiei, generally transmitted by skin-to-skin contact. It commonly affects young children (1) and elderly individuals (2). The mite resides in the epidermal and dermal layers of skin. Female mites make superficial tunnels in the stratum corneum of the host to lay her eggs, which is clinically represented as the burrow. Burrow is the pathognomonic sign of scabies infestation (3). However, it remains rarely encountered clinically as it gets destroyed/deroofed due to vigorous scratching. Burrow is commonly seen over finger webs, axilla, nipple, penile shaft, and flexural surfaces of the wrists. Traditional skin scraping examined under light microscope or videodermoscopy can identify mites, eggs, larvae, or feces of mites.
The clinical manifestation of scabies resembles other pruritic skin conditions like atopic dermatitis, contact dermatitis, dermatophytic infection, urticaria, and prurigo simplex. The pathognomonic burrow serves as a useful clue to the diagnosis, negating other differentials.
The condition can be treated with topical application of scabicidal agents (permethrin 5% cream, crotamiton) or systemic ivermectin (4).
Informed consent: Informed consent was obtained from the patient’s parent for publication of this case.
Funding: There are no funders to report for this submission.
Potential Conflicts of Interest: All authors: No reported conflicts of interest. All authors have submitted the ICMJE Form for Disclosure of Potential Conflicts of Interest. Conflicts that the editors consider relevant to the content of the manuscript have been disclosed.
References
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