Métodos de diagnóstico para estrongiloidíase humana: uma revisão literária

Abstract

Strongyloides stercoralis is a nematode considered to be one of the largest species of clinical importance to humans because of its prevalence, responsible for human strongyloidiasis, and has a broad spectrum of clinical manifestations. It presents asymptomatic pictures, demonstrating clinical states as acute, chronic and may progress to hyperinfection. The most severe form of the disease is known as disseminated strongyloidiasis and, in immunosuppressed patients, can be fatal. The diagnosis of strongyloidiasis is challenging as it is driven by clinical and epidemiological suspicions. In this work, a brief approach was given to laboratory diagnostic methods for human strongyloidiasis between 2001 and 2019. The results obtained indicate that the parasitic diagnosis is still routinely performed through fecal larvae research, but when its elimination is minimal and irregular, makes routine laboratory methods non-specific and non-sensitive. Because of this, it has been invested in different diagnostic methods for this disease, aiming to increase sensitivity and specificity. The laboratory procedures that can be used are the direct ones, which concentrate the larvae of S. stercoralis, such as the Hoffmann, Pons and Janer (HPJ) technique, the Baermann-Moraes method, the Rugai method, the Coproculture plaque blood agar and the Harada-Mori method. Indirect methods include polymerase chain reaction (PCR), serological assays such as indirect enzyme-linked immunosorbent assay (ELISA) and indirect immunofluorescence (IFN). Based on the information acquired, it can be concluded that the methods using serological samples are more sensitive and specific when compared to the techniques that use faecal samples. PCR, in turn, is one of the techniques that uses feces for its accomplishment and has a high sensitivity of detection of the presence of the parasite, mainly in recent infections.