Gynecomastia is the benign enlargement of male breast glandular tissue and is the most common breast condition in males. At least 30% of males will be affected during their life. Since it causes anxiety, psychosocial discomfort and fear of breast cancer, early diagnostic evaluation is important and patients usually seek medical attention. Gynecomastia was reported to cause an imbalance between estrogen and androgen action or an increased estrogen to androgen ratio, due to increased estrogen production, decreased androgen production or both. Evaluation of gynecomastia must include a detailed medical history, clinical examination, specific blood tests, imaging and tissue sampling. Individual treatment requirements can range from simple reassurance to medical treatment or even surgery. The main aim of any intervention is to relieve the symptoms and exclude other etiological factors.

Context: The aims of the study are to compare characteristics of subacute thyroiditis (SAT) related to different etiologies, and to identify predictors of recurrence of SAT and incident hypothyroidism. Methods: This nationwide, multicenter, retrospective cohort study included 53 endocrinology centers in Turkey. The study participants were divided into either COVID-19–related SAT (Cov-SAT), SARS-CoV-2 vaccine–related SAT (Vac-SAT), or control SAT (Cont-SAT) groups. Results: Of the 811 patients, 258 (31.8%) were included in the Vac-SAT group, 98 (12.1%) in the Cov-SAT group, and 455 (56.1%) in the Cont-SAT group. No difference was found between the groups with regard to laboratory and imaging findings. SAT etiology was not an independent predictor of recurrence or hypothyroidism. In the entire cohort, steroid therapy requirement and younger age were statistically significant predictors for SAT recurrence. C-reactive protein measured during SAT onset, female sex, absence of antithyroid peroxidase (TPO) positivity, and absence of steroid therapy were statistically significant predictors of incident (early) hypothyroidism, irrespective of SAT etiology. On the other hand, probable predictors of established hypothyroidism differed from that of incident hypothyroidism. Conclusion: Since there is no difference in terms of follow-up parameters and outcomes, COVID-19– and SARS-CoV-2 vaccine–related SAT can be treated and followed up like classic SATs. Recurrence was determined by younger age and steroid therapy requirement. Steroid therapy independently predicts incident hypothyroidism that may sometimes be transient in overall SAT and is also associated with a lower risk of established hypothyroidism.

Key words: Nephropathy; ET-1; VCAM-1; ICAM-1; FMD; endothelial dysfunction

Key words: Atypical parathyroid adenoma; parathyroid carcinoma; biochemical markers; ultrasound