What is the diagnostic stage of Strongyloides stercoralis?

The diagnostic stage of Strongyloides stercoralis is rhabditiform larvae. In the life cycle of this particular nematode, the presence of rhabditiform larvae in clinical specimens, such as stool samples, is what allows for the diagnosis of strongyloidiasis. These larvae are typically found in the feces of an infected host and can be identified through microscopic examination.

Rhabditiform larvae are important in distinguishing Strongyloides stercoralis from other helminths, as they exhibit specific morphological features that help in diagnosis, such as a prominent bulb in the esophagus and a tapered tail. In contrast, while adult stages can also cause infections, they are not typically used as a direct diagnostic criterion in laboratory settings. Recognizing rhabditiform larvae provides an effective means to confirm the presence of this pathogen and initiate appropriate treatment.