Wehner J H, Kirsch C M
Department of Medicine, Stanford University School of Medicine, San Jose, CA 95128, USA.
Semin Respir Infect. 1997 Jun;12(2):122-9.
Strongyloides stercoralis (SS) is endemic in tropical and subtropical areas worldwide and in the southeastern United States. The lifecycle of SS is both unique and complex. Human infection begins with the penetration of skin by filariform larvae that migrate hematogenously to the lungs. Larvae then ascend the airway, are swallowed, and mature in the gut. Unlike other nematodes, SS can autoinfect the same host and persist for decades. Categorization of infection includes acute, chronic-uncomplicated, and disseminated forms. Clinical manifestations depend on the particular organs involved. Fifteen to thirty percent of chronically infected people may be asymptomatic. On the other hand, SS may cause the adult respiratory distress syndrome, septic shock, and death. The diagnosis of SS infection is suspected in patients from endemic areas who have blood eosinophilia, and gastrointestinal or pulmonary symptoms. A definitive diagnosis is established by demonstration of SS larvae in stool, body fluids, or tissues. A presumptive diagnosis of SS infection can be achieved by serology. Thiabendazole is the mainstay of treatment, but repeat doses may be necessary if the parasite is not initially eradicated. The low incidence of disseminated SS in areas endemic for both SS and AIDS is surprising and unexplained.
粪类圆线虫（SS）在全球热带和亚热带地区以及美国东南部呈地方性流行。SS的生命周期既独特又复杂。人类感染始于丝状幼虫穿透皮肤，幼虫经血行迁移至肺部。然后幼虫沿气道上行，被吞咽，并在肠道内成熟。与其他线虫不同，SS可自身感染同一宿主并持续数十年。感染分类包括急性、慢性非复杂性和播散性形式。临床表现取决于所累及的特定器官。15%至30%的慢性感染者可能无症状。另一方面，SS可导致成人呼吸窘迫综合征、感染性休克和死亡。在来自流行地区且有血液嗜酸性粒细胞增多以及胃肠道或肺部症状的患者中怀疑有SS感染。通过在粪便、体液或组织中发现SS幼虫来确诊。可通过血清学进行SS感染的推定诊断。噻苯达唑是主要治疗药物，但如果寄生虫最初未被根除，可能需要重复给药。在SS和艾滋病均为地方性流行的地区，播散性SS的低发病率令人惊讶且无法解释。
