Endocrine Abstracts

Introduction: Blastocystissp. (BS) is the most common intestinal parasite that is isolated in human fecal samples. Its pathogenic role is still questioned. While some consider it a beneficial component of the human intestinal microbiota, some evidence relates it with dysbiosis and development of metabolic syndrome (MS). Its presence has been inversely correlated with BMI.

Objective: The objective of this study is two-fold: determining the prevalence of BS through molecular analysis fecal samples of Spanish obese subjects and relating it with the presence or absence of MS according to the NCEP ATP III definition.

Methods: Clinical, anthropometric and biochemical data were gathered from type II and type III obese subjects attended in an Obesity Unit in our hospital. Fecal samples were obtained in order to perform PCR amplification and rRNA small subunit sequencing of the BS gene. Anthropometric measurements and biochemical analysis were undertaken after an overnight fast. Waist circumference was recorded with a standard flexible non-elastic metric tape.

Results: Fecal samples were obtained from 65 obese subjects of 48.0 (±10.2) years old, 41 women and 24 men. Mean BMI was 45.5 kg/m² and every subject showed an abdominal circumference of high risk (130.1±13.6 cm). We obtained PCR positive results for BS in 28 samples (43.1%). 46.4% of BS positive patients were diagnosed with MS whereas 59.4% of BS negative subjects met the same criteria. Attending to individual comorbidities: 51.1% were hypertensive (56.7% in BS negative, 42.8% in BS positive), 68.0% dyslipidemic (no differences between groups), and 58.2% presented some kind of dysglicemic state (60.1% and 56.7%, respectively) with an incidence of type II DM of 28.5% in BS positive patients and 37.8% in BS negative patients. No differences were found between groups attending to plasmatic leptin levels (52.3 ng/ml in BS positive and 52.4 ng/ml in BS negative) or HOMA-R index (6.0 and 6.1, respectively), but higher insulin plasmatic levels (34.7 vs 21.2 mg/ml) were detected in the BS negative group.

Conclusions: Yet preliminary, these clinical results suggest a protective effect of BS in the development of MS in our population of obese subjects. However, no differences were found in analytical parameters of insulin-resistance, which has been described as the cornerstone of metabolic syndrome.