Scabies
摘要
Scabies is a common highly contagious and pruritic ectoparasitosis caused by the mite Sarcoptes scabiei hominis. The typical sign of scabies is the burrow, a threadlike, slightly elevated, and often serpiginous lesion ranging from 1 to 10 mm in length and ending in a tiny papule, the site of the adult mite. Other nonspecific findings include papules, nodules, pustules, and scratching marks. Dermatoscopy at ×10 shows the typical “jet with contrail” sign, where the triangular, brown “jet” corresponds to the pigmented anterior portion of the mite (mouthparts and two anterior pairs of legs) and the trailing, lighter “contrail” represents the burrow. Higher magnifications (> ×100) allow the detection of details such as mites in migration, along with its eggs and fecal pellets.