疥瘡

Scabies

疥瘡是皮膚感染了人疥蟎蟲。疥瘡通常是人與人之間的密切接觸而傳染，偶爾可透過衣物、床單而傳染。疥瘡的表現為劇烈搔癢，夜間尤甚，在感染部位會出現紅斑性丘疹。癢疹加上特殊病變分佈，合併有家庭成員同時感染的病史要強烈懷疑疥瘡。刮皮屑、皮膚鏡檢查、膠帶測試可用於疥瘡確診，但檢查陰性不能排除疥瘡診斷。疥瘡治療建議患者使用permethrin 5％乳膏進行治療（從頸部向下的所有區域，8至14小時後洗掉），一個星期後再擦一次。或是口服伊維菌素（Ivermectin）200微克／公斤體重，2週後重複一次。結痂型疥瘡治療要同時口服伊維菌素和塗抹permethrin 5％乳膏。治療時需同時治療病人和密切接觸者以減少疥瘡傳播，並降低疥瘡患者復發的風險。因為蟎離開人體皮膚只能存活2至3天，病人治療前3天內使用的衣物應裝袋靜置7天，或用熱水清洗並用烘乾機烘乾。

Scabies is an infestation of the skin caused by the mite Sarcoptes scabiei. Scabies is usually transmitted by close person-to-person contact, but can occasionally be transmitted by fomites such as clothing and linens. Scabies usually presents with severe itching, often worse at night, and erythematous papules in a characteristic distribution. The combination of a pruritic eruption with characteristic lesions and distribution, and family involvement strongly suggests the diagnosis. Skin scrapings, dermoscopic examination, and an adhesive tape test can be used for confirmation of scabies infestation, but negative tests do not rule out the diagnosis. Patients with scabies can be treated with permethrin 5% cream twice, one week apart (applied to all areas of the body from the neck down and washed off after eight to fourteen hours) or oral ivermectin (200 mcg/kg stat and repeated after two weeks). Patients with crusted scabies should be treated simultaneously with oral ivermectin and topical permethrin 5% cream. Simultaneous treatment of the patient and close contacts is recommended to reduce risk of spread and recurrence of scabies in the treated patient. Because mites usually survive for only two to three days when not on human skin, clothing and linens used within the preceding three days should be washed in hot water and dried in a hot dryer or bagged for seven days.