Epidemiology Strongyloidiasis is acquired when infectious larvae in the soil penetrate human skin, migrate within the circulation and develop into adult worms in the gut. Female worms shed larvae in the gut, the larvae in the stool reach the soil, and the cycle is completed. The worms can also complete a life cycle within a human host without a soil phase. The number of worms may increase greatly in immunosuppressed persons. Pulmonary involvement with wheezing, chest pain and cough can also occur.
Eosinophilia is usually present, unless the patient is immunosuppressed.
Overwhelming infection in untreated immunosuppressed persons can be fatal. Diagnosis Stool microscopy may reveal the rhabditiform larvae of S. stercoralis . These larvae, which have a short buccal capsule, can be infrequently detected despite multiple investigations. Furthermore, unless high power is used, Strongyloides larvae can be difficult to distinguish from hookworm larvae, which have a longer buccal capsule. Serology can be helpful in confirming the diagnosis.