Gut Microbiome Lactobacillus acidophilus and its Relation to Thyroid Nodules and Thyroid Hormonal Profile

Abstract Background Thyroid nodules are a common clinical problem. Epidemiologic studies have shown that the prevalence of palpable thyroid nodules is approximately 5% in women and 1% in men living in iodine-sufficient parts of the world. It is well-known that any thyroid disease is closely related to thyroid hormone levels or the hormone functioning, which could influence the gut microbiomes composition. Lactobacillus is an important genus in the human gut which could improve the concentration of various trace elements in human cells. Aim of the Work To assess the relation between gut microbiome Lactobacillus acidophilus and its relation to thyroid nodules and thyroid hormonal profile. Patients and Methods This was a case control study that was conducted on 90 Egyptian subjects aged 16-60 years old that was divided into 3 groups, Group A that included 30 patients with benign thyroid nodule Group B that included 30 patients with Malignant thyroid nodule and Group C that included 30 healthy subjects as a control group, it was carried out at Endocrine outpatient clinic at Ain Shams University Hospital in Cairo, Egypt. It was conducted from September 2021 till September 2022. Systematic random sampling was performed. Results There was a significant increase in cycle threshold at which lactobacillus acidophilus PCR expressed (which indicate lower colony count of lactobacillus acidophilus) in group B (malignant thyroid nodules) than group C (control group) with P < 0.001 and there was a significant increase in cycle threshold at which lactobacillus acidophilus PCR expressed in group A (benign thyroid nodules) than group C (control group) with P value 0.003. Serum Selenium in Group (B) (malignant thyroid nodule) was lower than in Group (C) (healthy control) There was high statistically significant differences between groups (P-Value <0.001*). Serum Selenium in Group (A) (Benign thyroid nodule) was lower than in Group (C) (healthy control) There was high statistically significant differences between groups (P-Value <0.001*). Serum zinc was lower in Group (A) (benign thyroid nodule) than Group (C) (healthy control) There was high statistically significant differences between groups (P-Value <0.001*). Serum zinc was lower in Group (B) (Malignant thyroid nodule) than Group (C) (healthy control). There was high statistically significant differences between groups (P- Value <0.001*). Conclusion Stool Lactobacillus acidophilus count was significantly different between studied groups. Being lower in patients with thyroid cancer and patients with benign thyroid nodules than healthy group. This data may reflect the interaction between the gut microbiota lactobacillus acidophilus and the development of thyroid nodules and thyroid cancer.