Background/Objectives: Hashimoto’s thyroiditis (HT) is an autoimmune disease influenced by genetic factors and environmental triggers that affect immune system function. Data suggest that vitamin D may also play a role in the etiopathogenesis of HT. Methods: This retrospective study included patients admitted to the Endocrinology and Metabolic Diseases Outpatient Clinic. Data from individuals aged 18 years and older were analyzed, including serum levels of thyroid-stimulating hormone (TSH), free triiodothyronine (fT3), free thyroxine (fT4), anti-thyroid peroxidase (anti-TPO), anti-thyroglobulin (anti-TG), and vitamin D. HT was diagnosed based on the presence of anti-TPO and/or anti-TG antibodies, while individuals with negative results for both were classified as non-HT. Thyroid function was categorized as euthyroid if TSH levels were between 0.55 mU/L and 4.78 mU/L and fT4 levels were between 0.89 ng/dL and 1.76 ng/dL; hypothyroid status was defined as TSH > 4.78 mU/L. Vitamin D levels were classified as deficient (<50 nmol/L), insufficient (50–74.9 nmol/L), or sufficient (≥75 nmol/L). Results: Of the total participants, 25,018 did not have HT, while 27,800 were diagnosed with HT. Vitamin D level was significantly higher in the HT group than the non-HT group (41.43 nmol/L and 39.44 nmol/L, p < 0.001). Vitamin D deficiency was present in 65.5% of the non-HT group and 62.1% of the HT group (p < 0.001). Subgroup analyses based on thyroid function showed that vitamin D levels were highest in the euthyroid HT group and similar in the euthyroid non-HT, hypothyroid non-HT, and hypothyroid HT groups (p < 0.001). Conclusions: In conclusion, while vitamin D levels were higher in the HT group compared to the non-HT group, no clinically significant association between vitamin D levels and HT or autoantibody positivity was observed. Vitamin D deficiency was more prevalent in the hypothyroid group compared to the euthyroid group. This study suggests that although vitamin D deficiency may not be directly involved in the pathogenesis of HT, it may still play a role in modulating immune activity or influencing the disease phenotype..

Aim: The increasing prevalence of diabetes mellitus (DM) brings about a rise in nephropathy, retinopathy, and neuropathy, which are microvascular complications of diabetes. The triglyceride-glucose (TyG) index is a convenient indicator of insulin resistance. It is related to microvascular and macrovascular complications among nonhospitalized patients with diabetes. However, it is unclear if the TyG index poses risks for vascular complications of type 2 DM in hospitalized patients. This study aims to investigate possible relations between this index and the risk of microvascular complications in hospitalized patients with type 2 DM. Material and Methods: The present study included 420 type 2 DM patients who were hospitalized in our clinic between February 2019 and May 2022. The TyG index was measured as fasting triglycerides mg/dL × fasting glucose mg/dL/2. The presence of microalbuminuria (MAU), diabetic neuropathy, chronic kidney disease (CKD), and retinopathy (DR) were evaluated. The data were analzed using IBM SPSS 22.0 statistical software. The level of statistical significance was taken as p

Aim: This study aimed to investigate the possible relationships between ABO and Rh blood groups and microvascular complications of diabetes in type 2 diabetes mellitus (DM) patients. Material and Methods: This study included Type 2 DM patients who were hospitalized and followed in our clinic between February 2019 and April 2022. The patients’ data files were retrospectively reviewed in order to record demographic characteristics, antidiabetic medications, comorbid diseases, fasting plasma glucose, HbA1c values, ABO/Rh blood groups, and microvascular complication status (nephropathy, retinopathy, and neuropathy). Results: A total of 348 patients were included in the study. In the sample group, male patients constituted 40.9% (142) and female patients 59.1% (206) of the sample, and the mean age was 59.3±12.8 years. Diabetic nephropathy, retinopathy, and neuropathy rates were 31.3%, 41.0%, and 52.0%, respectively. The blood group was A in 151 (43.4%), B in 51 (14.6%), 0 in 127 (36.5%), and AB in 19 (5.5%) patients. Patients with different blood types did not show any significant differences in the microvascular complications of diabetes. The frequency of nephropathy and retinopathy were lower in Rh-negative patients than in Rh-positive patients (p=0.044 and p=0.041, respectively). Conclusion: ABO blood groups are not correlated with the microvascular complications of diabetes in patients with type 2 DM. However, Rh positivity may pose certain risks for nephropathy and retinopathy.

Aims: Primary hyperparathyroidism (PHPT), a well-recognized endocrine disorder, is subclassified into hypercalcemic and normocalcemic forms. Recent studies suggest that biochemical ratios such as the chloride-to-phosphorus (Cl/P) and chloride-to-magnesium (Cl/Mg) ratios may aid in the diagnostic evaluation and risk stratification of PHPT-related complications. This study aimed to investigate the diagnostic and predictive utility of the Cl/P and Cl/Mg ratios in differentiating PHPT subtypes and assessing the risk of osteoporosis and nephrolithiasis. Methods: This retrospective study included 116 patients who underwent parathyroidectomy for PHPT at Ankara Bilkent City Hospital between 2019 and 2022. All patients met surgical criteria based on international guidelines, and normocalcemic PHPT (N-PHPT) cases were defined by repeatedly normal calcium measurements and exclusion of secondary causes. Preoperative biochemical parameters, imaging findings, and complication profiles were analyzed. Cl/P and Cl/Mg ratios were calculated and evaluated using the Mann-Whitney U test, Spearman correlation, and receiver operating characteristic (ROC) analysis. Results: The Cl/P ratio was significantly higher in hypercalcemic PHPT than in normocalcemic patients (median 42.4 vs. 38.3, p=0.0125) and was positively associated with bone mineral density. A Cl/P threshold of >43.6 yielded 80.0% specificity in distinguishing PHPT subtypes [area under the curve (AUC): 64.1%]. The Cl/Mg ratio, although not differing between subtypes, was significantly associated with nephrolithiasis risk, with a cut-off value of ≤55 providing 82.4% sensitivity and 66.7% specificity (AUC: 70.5%, p

Objective: The 2022 WHO classification introduced differentiated high-grade thyroid carcinoma (DHGTC) as a distinct category characterized by high-grade features despite maintained differentiation. Therefore, this study aims to evaluate its clinical characteristics, treatment responses, and the prognostic impact of the Ki-67 proliferation index in this patient population. Methods: We retrospectively reviewed 3100 patients with differentiated thyroid carcinoma (DTC) between 2017 and 2024. From this baseline pool, a total of 56 patients (1.8%) were identified and re-classified as DHGTC based on mitotic count (≥5/2 mm²) and/or tumor necrosis. Additionally, 69 DTC patients (2.2%) with an elevated Ki-67 index (>5%) identified from the same baseline pool—representing an overlapping group with the DHGTC cohort—were analyzed to evaluate its clinical significance. Results: In the DHGTC group, tumor necrosis was present in 87.5% and high mitotic activity in 19.6% of cases. While all DHGTC patients were classified as high-risk under 2025 American Thyroid Association (ATA) guidelines, 42.8% showed biochemical or structural incomplete response at the last follow-up and 28.6% required additional salvage interventions. In the broader DTC cohort, Ki-67 ≥ 15% was significantly associated with older age, larger tumor size, extensive invasion, and poorer treatment response (p < 0.05). However, within the DHGTC subset, Ki-67 ≥ 15% was only significantly associated with increased lymphovascular invasion and more extensive surgery. Conclusions: DHGTC carries a significant burden of aggressive histopathological features and a high risk of structural disease persistence or recurrence. While an elevated Ki-67 index (≥15%) serves as an adverse marker in general DTC, its additional prognostic value within the high-grade DHGTC cohort remains inconclusive, potentially obscured by limited statistical power due to small subgroup sizes.

Objective: Primary aldosteronism (PA) is a common cause of endocrine hypertension, yet there are some difficulties in diagnosing the disease. The saline infusion test (SIT), a standard confirmatory test, has limitations such as contraindications, hospitalization, and high cost. This study evaluates the potential of the plasma aldosterone/potassium (A/K) ratio in predicting PA. Methods: The study included 118 patients who underwent SIT; 57 were diagnosed with PA based on positive SIT and/or captopril challenge test results, adrenal imaging, and multidisciplinary clinical judgment. Aldosterone, plasma renin activity, and potassium and aldosterone-to-renin ratio (ARR) levels at admission, as well as SIT results and imaging findings, were retrospectively reviewed and compared between patients with and without PA. Results: Patients with PA had higher aldosterone levels (P < .001) and ARR (P < .001) but lower potas sium levels (P < .001) and PRA (P = .01). The A/K ratio was significantly higher in the PA group (P < .001). Receiver operating characteristic analysis showed that an A/K ratio cut-off of 5.4 could distin guish PA patients from non-PA patients [AUC (95% CI) = 0.811 (0.733-0.890), P < .001], with 73.7% sensitivity and 77.0% specificity. Univariate and multivariate analyses indicated that a high A/K ratio increased the likelihood of a PA diagnosis, with an A/K ratio above 5.4 associated with a 4.585-fold higher risk (95% CI: 1.181-17.799, P = .028). Conclusion: The A/K ratio may predict PA. It offers advantages such as no need for potassium replace ment or hospitalization, making it a useful supplementary parameter for diagnosing PA, particularly in patients for whom confirmatory tests are unsuitable. Cite this article as: Demirel KD, Dellal Kahramanca FD, Karaahmetli G, et al. Value of plasma aldosterone/potassium ratio in predicting primary aldosteronism in patients scheduled for confirmatory testing. Endocrinol Res Pract. 2025;29(4):333-337.