Clinical significance and prevalence of Blastocystis hominis in Van, Turkey

OBJECTIVES To determine the associated clinical symptoms and prevalence of Blastocystis hominis (B. hominis).  METHODS Stool samples of 50,185 patients (26,784 males and 23,401 females) who were received at the Parasitology Laboratory of Yuzuncu Yil University Faculty of Medicine, Van, Turkey in the last 5 years were inspected microscopically using saline and iodine-stained wet-mount preparations. Age, gender, and symptoms of patients were recorded and their significance was evaluated.   RESULTS   The prevalence of B. hominis in the total sample was 0.54% (275/50185). Out of 275 infected patients, 143 (52%) were males, and 132 (48%) were female (χ2=0.884; p=0.348). The distribution of B. hominis infection was high in 7-13 aged children (34.9%) (χ2=306.8; p=0.001). Blastocystis was higher among symptomatic patients (70.2%) compared with asymptomatic patients (29.8%) (χ2=107.13; p=0.001). The most frequent clinical symptoms associated with the disease were abdominal pain (27.3%) and diarrhea (19.6%) followed by anorexia, fever, saliva, anal itching, and nausea.  CONCLUSION Blastocystis hominis is considered a causative agent of human disease in patients with recurrent symptoms. Due to the significant risk for zoonotic transmission, molecular techniques must be used to determine the route and source of infection.