Moving forward Strongyloides stercoralis detection, studying molecular typing as infection follow up strategy in immunocompromised patients

REPETTO, S.; ARGÜELLO, L.; BATALLA, E.; BURGOS, J.; CAPPA, S. GONZALEZ; SOTO, C. ALBA; RISSO, M.; RUYBAL, P.

INTERNATIONAL JOURNAL OF INFECTIOUS DISEASES : IJID : OFFICIAL PUBLICATION OF THE INTERNATIONAL SOCIETY FOR INFECTIOUS DISEASES.

ELSEVIER SCI LTD

Año: 2018 vol. 73

1201-9712

Background: Strongyloides stercoralis is a geohelminth which affects 10-40% of the world population in tropical and subtropical areas. It produces chronic infections and severe symptoms in immunocompromised patients with high mortality. Although the parasitological cure is defined as the absence of larvae after one year of treatment, we have observed reactivations after the second year. We evaluated genetic diversity and its possible association with the clinical characteristics and evolution of this parasitosis.Methods & Materials: Twenty-two patients (18 immunocompromised) with diagnosis and follow-up of strongyloidosis from Argentina, Bolivia, Paraguay, Peru and Dominican Republic were evaluated. The DNA extracted from stool sample at the time of diagnosis was used as a template for amplification and sequencing of a 404 bp region of the mitochondrial gene cox1. The analysis of sequences was: consensus assembly (STADEN), alignment (MEGA6), haplotype resolution (PHASE, DNAsp), allele coding and discriminatory power calculation (PD, MLSTest). Sequences were analyzed in the context of sequences of S. stercoralis (581), S. fuelleborni, S. ratti, S. venezuelensis, S. planiceps, S. mirzai and S. papillosus. Results were expressed in frequencies and percentages. Level of significance was p  0.05). However, in all immunocompromised patients who reactivated (7/18), the HP24 variant of the parasite was detected. The presence of HP24 increased the risk of reactivation with a RR of 2.16 (p