BLASTOCYSTIS SUBTYPE 3 AMONG ADOLESCENTS WITH GASTROINTESTINAL SYMPTOMS IN FAYOUM GOVERNORATE, EGYPT

Blastocystis is a common polymorphic protozoan infecting human intestine with a zoonotic potential. Despite the unclear pathogenicity, its existence may be linked to a wide range of gastrointestinal disorders. The present cross sectional study was conducted to analyze Blasto-cystis subtypes among 110 adolescents suffering from disturbing GIT symptoms in stool samples. Positive samples (21 (19.1%)) by microscopy were subjected to DNA isolation and sub-typed by Sequence Tagged Site (STS)-PCR analysis, which successfully subtyped 10 (62.5%) of 16 isolates. The dominant Blastocystis subtype was ST3 in 6 (40%) samples followed by 3 (30%) for ST2, but one sample (10%) was amplified for ST1. The results revealed significant association between nausea and vomiting and Blastocystis infection. However, there was no difference between the Blastocystis subtypes and demo-clinical characteristics.