Geographic variation in the association between Hashimoto's thyroiditis and Papillary thyroid carcinoma, a meta-analysis.

PURPOSE: The association between papillary thyroid cancer (PTC) and Hashimoto's thyroiditis (HT) remains a matter of debate. Several genetic and environmental factors have been found to influence this association. Because of the variation in these factors among different populations, we conducted a country- and region-based meta-analysis to examine whether the geographic area influences this association. METHODS: We searched PubMed and Web of Science databases for original articles that investigated the association between HT and PTC from February 1955 to February 28, 2023. The included studies were stratified according to their country and region of origin. Various subgroup analyses were conducted. The primary outcome was the pooled relative risk (RR) and its 95% confidence interval (CI) for each region and country. RESULTS: Forty-six studies including a total of 93,970 participants met our inclusion criteria. They originated from 16 countries distributed in five regions. Significant variation was found among countries but not among regions. Upon analysis of all 46 included studies, countries were classified based on their RR and its 95% CI. Excluding countries with pooled sample sizes <500, Sri Lanka (RR 4.23, 95% CI 2.91-6.14), Poland (RR 3.16, 95% CI 2.79-3.57) and Japan (2.68, 2.14-3.36) showed the strongest association between HT and PTC while Greece (RR 1.06, 95% CI 1.00-1.13), Spain (RR 0.70, 95% CI 0.23-2.11), and Jordan (0.62, 0.32-1.32) showed no significant association. CONCLUSION: Our findings revealed a variation in the association between HT and PTC among countries but not among regions. The country-to-country variation could be due to certain genetic and/or environmental factors subject to geographic variation that influence this association. These findings may help guide health policies aiming to mitigate the risk of PTC in the HT population by helping identify high-risk and low-risk countries.

Detection of Methicillin Susceptible and Resistant Staphylococcus aureus Nasal Carriage and Its Antibiotic Sensitivity among Basic and Clinical Years Medical Students.

Background: Healthcare workers (HCWs) and medical students can be asymptomatic carriers in transmitting methicillin resistant and susceptible Staphylococcus aureus (MRSA and MSSA). Studying epidemiological and antibiotic susceptibility data is necessary to limit the spread of infections, help with treatment and understand the transmission dynamics of MSSA and MRSA. Our study assessed the rate of MSSA and MRSA nasal carriage and its antibiogram among medical students in basic and clinical years at the University of Jordan. Methods: A total of 210 nasal swabs were randomly collected from participants. MSSA and MRSA were identified by culture, biochemical and other phenotypical analysis methods. Antibiotic susceptibility was determined by the disc diffusion method. Results: The nasal carriage of MSSA was 6.6% and 11.4% and that of MRSA was 1.9% and 2.8% among basic and clinical years, respectively. There was no significant difference for the nasal carriage of MSSA and MRSA among basic and clinical year students (p value ≥ 0.05). MSSA resistance ranged between 25% and 33% for trimethoprim-sulfamethoxazole, tetracycline and ciprofloxacin. For MRSA, the highest resistance was to trimethoprim-sulfamethoxazole and tetracycline (67% to 100%), followed by gentamicin and ciprofloxacin (33% to 67%), in all participants in the study. Conclusion: The difference in the carriage rates of MSSA and MRSA among basic and clinical students was statistically insignificant. The continuous awareness and implementation of infection control procedures and guided patient contact are recommended. The results might also suggest that healthcare workers could be victims in the cycle of MRSA nasal carriage, a theory that needs further study.