The patient is a 24-year-old man who complains of an itchy rash affecting his hands, feet, and abdomen. The itching has increased in severity despite the use of oral and topical steroids. He states that other family members are unaffected and his current girlfriend denies symptoms. Examination reveals multiple excoriated papules of the affected areas.
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Scabies is a skin infestation caused by the mite Sarcoptes scabiei. The condition is most commonly encountered in overcrowded areas and in patients with poor personal hygiene.1 The most prominent clinical feature is intense itching often worse at night. The pruritus is the result of a delayed type-IV hypersensitivity to the mite, its feces, and its eggs.2 The pathognomonic findings are burrows and small erythematous papules tipped with excoriated and hemorrhagic crusts.
Successful treatment requires eradication of the mites and is accomplished with either topical or oral anti-scabetic agents. Close contacts should be treated simultaneously. Oral ivermectin favors compliance compared with permethrin cream, although the latter has greater rate of cure.3,4
Rebecca Geiger is a physician assistant at the Dermdox Center for Dermatology in Hazleton, PA. Dr. Schleicher is director of the DermDox Center for Dermatology, as well as an associate professor of medicine at the Commonwealth Medical College and a clinical instructor of dermatology for Arcadia University and Kings College.
- Camacaro L, Reales E. Scabies. J Am Acad Dermatol. 2015;72:AB129.
- Chosidow O. Clinical practices. Scabies. N Engl J Med. 2006;354:1718.
- Currie BJ, McCarthy JS. Permethrin and ivermectin for scabies. N Engl J Med. 2010;362:717.
- Dhana A et al. Ivermectin versus permethrin in the treatment of scabies: A systematic review and meta-analysis of randomized controlled trials. J Am Acad Dermatol. 2018;78:194-198.