Higher prevalence of Blastocystis hominis in healthy individuals than patients with gastrointestinal symptoms from Ahvaz, southwestern Iran.

BACKGROUND

Blastocystis, a common intestinal protozoan of humans and animals, infected more than 1 billion people around the world. This enteric protozoan is frequently reported in both healthy individuals and patients with gastrointestinal (GI) symptoms.

METHODS

Three hundred and forty-five fecal samples including 151 GI patients and 194 healthy individuals were examined by microscopy, culture and PCR-sequencing techniques to determine Blastocystis frequency and subtype (ST) variation.

RESULTS

The occurrence of Blastocystis was detected 56 (16.2%) and 85 (24.6%) by microscopy, culture and PCR methods, respectively. Out of the 85 positive patients, 60 (70.6%) were asymptomatic and 25 (29.4%) were symptomatic. The results of 41 successfully sequenced isolates identified 8 (19.5%), 8 (19.5%), and 25 (61.0%) ST1, ST2, and ST3, respectively.

CONCLUSION

This study has found that Blastocystis was more common in healthy individuals than GI patients. Another finding was that no correlation was found between clinical symptoms and Blastocystis STs.