Abstract

VISCIARELLI, Elena Concepción et al. Blastocystis: estudio coproparasitológico, clínico-epidemiológico y de prevalencia de subtipo 3 en pacientes de hospitales de Bahía Blanca, Argentina. Acta bioquím. clín. latinoam. [online]. 2021, vol.55, n.2, pp.195-206. ISSN 0325-2957.

Blastocystis is the unicellular parasite of the intestine of man and other animals,most prevalent in humans. It has a great genetic variety with multiple subtypes (ST). Although it has been associated with intestinal and extraintestinal disorders, its pathogenicity remains unclear. Four hundred and sixty one stool samples from symptomatic (n=380) and asymptomatic(n=81) patients from hospitals in Bahía Blanca, Argentina were analysed; informed consent was requested and an epidemiological file was completed. Coproparasitological analysis, morphometry, counting and typing of Blastocystis ST3 were performed by PCR. The population was: 57.3% female and 42.7% male.The prevalence of Blastocystis was 31.0% and that of Blastocystis ST3 62%. Vacuolar, granular and cystic forms were found, with vacuolar forms being the most frequent. Blastocystis were small and scarce in 64.8% of the samples. Most of the symptomatic patients (88.4%) presented gastrointestinal disorders, urticaria 4% and fever, anemia and low weight 7.6%; 66.7% of the urticaria patients presented Blastocystis. The presence of symptoms was significantly associated with Blastocystis (p<0.002). No statistical associations were found between Blastocystis, age, sex, availability of drinking water, sewage, and contact with animals. Within the symptoms, only statistical association of Blastocystis with urticaria was found (p<0.007). There was no association between Blastocystis ST3 and symptomatology. The results highlight the high prevalenceof Blastocystis and Blastocystis ST3, the need for a thorough coproparasitology, their statistical association with urticaria and the importance of not ignoring it in the health-disease process.

Keywords : Blastocystis spp; Blastocystis ST3; Coproparasitological analysis; Prevalence; Urticaria; Bahía Blanca; Argentina.