Detection of Blastocystis sp. Infection using different investigation techniques in children with or without acute diarrhea

Abstract

from two different pediatric emergency services, and randomly chosen 219 school children of 6 and 13 years of age from different socioeconomic environments and who did not have diarrhea. Stool samples were prepared with native-lugol and examined and then stained with trichrome and further examined under a light microscope.Genomic DNA was extracted from the stool samples using QIAamp® DNA Stool Mini Kit The extracted DNA samples were examined in terms of the presence of Blastocystis sp. using the realtime PCR method with the genesig® Standard Kit (Primer Design., UK) designed for the quantification of the Blastocystis G elongation factor-1 alpha gene. The PCR was performed using seven subtypespecific sequenced tagged site (STS) primers (SB83, SB155, SB227, SB332, SB340, SB336 and SB337) for the genotyping of Blastocystis sp. The collected data was analyzed using the SPSS (Version 17, Chicago IL, USA).Results: 115 samples were found positive for Blastocystis sp.. Subtyping was successfully performed on 46 samples using sequenced-tagged site (STS) primers and the PCR method. The most frequently detected subtype was ST3 (43.4%) followed by ST1 (26.1%), ST4 (10.9%) and ST2 (8.7%). The mixed subtypes were identified in five samples (10.9%) as; ST1+ST3 (n = 3), ST1+ST2 (n = 1) and ST2+ST3 (n = 1). None of the samples had ST5, ST6 or ST7. No statistically significant difference was found between the symptomatic and asymptomatic groups in terms of the Blastocystis sp. positivity and the distribution of subtypes (p > 0.05).