Identifying Clinical Characteristics of Hypoparathyroidism in Turkey: HIPOPARATURK-NET Study.

Hypoparathyroidism is an orphan disease with ill-defined epidemiology that is subject to geographic variability. We conducted this study to assess the demographics, etiologic distribution, treatment patterns and complication frequency of patients with chronic hypoparathyroidism in Turkey. This is a retrospective, cross-sectional database study, with collaboration of 30 endocrinology centers located in 20 cities across seven geographical regions of Turkey. A total of 830 adults (mean age 49.6 ± 13.5 years; female 81.2%) with hypoparathyroidism (mean duration 9.7 ± 9.0 years) were included in the final analysis. Hypoparathyroidism was predominantly surgery-induced (n = 686, 82.6%). The insulting surgeries was carried out mostly due to benign causes in postsurgical group (SG) (n = 504, 73.5%) while patients in nonsurgical group (NSG) was most frequently classified as idiopathic (n = 103, 71.5%). The treatment was highly dependent on calcium salts (n = 771, 92.9%), calcitriol (n = 786, 94.7%) and to a lower extent cholecalciferol use (n = 635, 76.5%) while the rate of parathyroid hormone (n = 2, 0.2%) use was low. Serum calcium levels were most frequently kept in the normal range (sCa 8.5-10.5 mg/dL, n = 383, 46.1%) which might be higher than desired for this patient group. NSG had a lower mean plasma PTH concentration (6.42 ± 5.53 vs. 9.09 ± 7.08 ng/l, p < 0.0001), higher daily intake of elementary calcium (2038 ± 1214 vs. 1846 ± 1355 mg/day, p = 0.0193) and calcitriol (0.78 ± 0.39 vs. 0.69 ± 0.38 mcg/day, p = 0.0057), a higher rate of chronic renal disease (9.7% vs. 3.6%, p = 0.0017), epilepsy (6.3% vs. 1.6%, p = 0.0009), intracranial calcifications (11.8% vs. 7.3%, p < 0.0001) and cataracts (22.2% vs. 13.7%, p = 0.0096) compared to SG. In conclusion, postsurgical hypoparathyroidism is the dominant etiology of hypoparathyroidism in Turkey while the nonsurgical patients have a higher disease burden with greater need for medications and increased risk of complications than the postsurgical patients.

Central venous sampling and magnetic resonance imaging in the diagnosis of ACTH-dependent Cushing's syndrome.

OBJECTIVES: Central venous sampling (CVS) with corticotropin-releasing hormone (CRH) stimulation is a crucial technique in evaluating adrenocorticotropic hormone (ACTH)-dependent Cushing's syndrome (CS). We evaluated central venous sampling (CVS) and magnetic resonance imaging (MRI) findings in predicting the localization and lateralization of pituitary microadenomas. METHODS: We analyzed 29 patients with CS who underwent CVS with CRH stimulation and examined with MRI retrospectively. Catheterization to central sinuses was successfully performed in 26 patients. Three patients with variant anatomy or inability to cannulate were diagnosed with CD after examination of pathology. RESULTS: After CVS, among 26 patients, 23 patients were determined to have CD (88.4%) and 2 (7.7%) patients were diagnosed with ectopic ACTH syndrome. One patient was diagnosed with CD postoperatively. While the sensitivity of the CVS was 95.6%, sensitivity of the preoperative pituitary MRI was lower (69.5%). Also, the negative predictive value ratio was higher in CVS than in MRI (66% versus 22%). Diagnostic accuracy in the lateralization of the tumor was high as in CVS as in MRI (76.4% versus 73.9%). CONCLUSION: Central venous sampling with higher sensitivity in the localization of pituitary microadenoma, also has approximately similar diagnostic accuracy in lateralizing the tumor with MRI.