DISCORDANCE BETWEEN GH AND IGF-1 LEVELS IN TURKISH ACROMEGALIC PATIENTS.

OBJECTIVE: Discordance between insulin-like growth factor-1 (IGF-1) and growth hormone (GH) levels is an important problem in the follow-up of patients diagnosed with acromegaly. Our aims were to evaluate the discordance between IGF-1 and GH levels and compare the performance of different cut-off levels for the nadir in GH (GHn) in acromegalic patients. METHODS: The study included 63 acromegalic patients in a follow-up at a tertiary care university hospital facility. Levels of IGF-1, IGF binding protein-3 (IGFBP-3), and GH were investigated. The baseline GH and GHn levels were evaluated after an oral glucose tolerance test (cut-offs of 0.4 and 1 ng/mL, respectively). The discordance rates between GHn and IGF-1 levels, and IGF-1/IGFBP-3 ratios were determined. RESULTS: We first adopted a GHn cut-off value of 1 ng/mL and found that 27 patients (42.9%) exhibited biochemical remission (BR) (IGF-1 <95th percentile, GH <1), and 25 patients (39.7%) had no BR (NBR) (IGF-1 ≥95th percentile, GH >1). Discordance in the presence of normal IGF-1 and nonsuppressed GH (DC1) occurred in 2 of 63 (3.2%) patients; discordance in the presence of high IGF-1 and suppressed GH (DC2) occurred in 9 of 63 (14.3%) patients. If the GHn cut-off value adopted was 0.4 ng/mL, the distributions were 17 of 63 (27.0%) patients in BR, 29 of 63 (46.0%) patients in NBR, 12 of 63 (19.0%) in DC1, and 5 of 63 (7.9%) patients in DC2. If only the baseline GH values were considered, the distributions were very similar to those with a GHn cut-off value of 0.4 ng/mL. The IGF-1/IGFBP-3 ratio was lowest in the BR group. CONCLUSION: Adopting a GHn cut-off value of 0.4 ng/mL did not increase the test performance compared with baseline GH only. In contrast, in the follow-up of acromegalic patients, the IGF-1/IGFBP-3 ratio might be a useful measurement when discordance between IGF-1 and GH levels occurs. We propose that these values be considered in clinical practice. ABBREVIATIONS: BR = biochemical remission DC1 = discordance group 1 DC2 = discordance group 2 DM = diabetes mellitus GH = growth hormone GHn = nadir in GH IGF-1 = insulin-like growth factor-1 IGFBP-3 = IGF binding protein-3 LAR = long-acting release NBR = not in biochemical remission OGTT = oral glucose tolerance test.

The Association of Histologically Proven Chronic Lymphocytic Thyroiditis with Clinicopathological Features, Lymph Node Metastasis, and Recurrence Rates of Differentiated Thyroid Cancer.

The influence of chronic lymphocytic thyroiditis (CLT) on clinicopathological features and behavior of differentiated thyroid carcinoma (DTC) is still debated. In the present study, we aimed to evaluate the prognosis of DTC on the presence of CLT. A total of 649 total thyroidectomized patients (379 female, 270 male) with DTC, who had follow-up data for at least 36 months were included. Clinical, histopathological data, preoperative thyroid peroxidase antibody (TPO-ab), thyroglobulin antibody (Tg-ab), thyroid-stimulating hormone (TSH) levels, and presence of recurrent/persistent disease (R/PD) were evaluated retrospectively. Presence of CLT was defined by histopathology. Frequency of CLT was 32% (n = 208) among DTC patients. Mean tumor size (maximal diameter) was smaller in CLT group when compared to non-CLTs (p = 0.006). Capsular invasion, vascular invasion, tumor stage, risk groups, and R/PD were negatively associated with CLT (p < 0.01, p = 0.04, p = 0.03, p = 0.02, p < 0.01, respectively). Extrathyroidal extension was more frequent in non-CLT group when compared CLT (p = 0.052). Preoperative TSH level was positively associated with lymph node metastasis (LNM) and higher in patients with lateral LNM when compared to central LNM (p < 0.01). Central LNM, lateral LNM, stage 4 tumor, and intermediate- and high-risk tumor groups increased the risk of R/PH, 2.5-, 2.9-, 12.7-, 2.3-, and 4.2-fold, respectively. Presence of CLT was independently related with favorable outcomes, as the risk of R/PD was decreased by 0.49-fold. In conclusion, coexistence of CLT was negatively associated with tumor size, capsular invasion, vascular invasion, and tumor stage in DTC. Risk of R/PD was decreased by approximately half in patients with CLT.

Epidemiologic survey: reference ranges of serum insulin-like growth factor 1 levels in Caucasian adult population with immunoradiometric assay.

Gender, age adjusted, population based reference ranges are necessary to use insulin-like growth factor 1 (IGF-1) as a diagnostic marker or for therapeutic monitoring in growth hormone (GH) related diseases. The aim of the present study was to describe the serum IGF-1 distribution and to calculate age and gender specific reference values for Caucasian adult population. A representative sample of 1002 male and 1039 female, totally 2041 participants aged above 18 years old was examined. The subjects suffering from diabetes mellitus, renal diseases, liver diseases, cancer, or diseases of pituitary gland were excluded by medical history, physical examination, and laboratory tests. The subjects were not using any drug that could affect IGF-1 levels. Body mass index (BMI)>30 or<18 kg/m2 were excluded. Serum IGF-1 concentrations were determined by immunoradiometric assay (IRMA). Serum IGF-1 concentrations were declined with age in both males and females after the age of 18. Males had significantly higher serum IGF-1 levels than females in the age groups 18-24, 50-69 (P<0.05), but not in others (P>0.05). The present study established age and gender specific reference ranges for serum IGF-1 levels calculated for Caucasian adult population with IRMA that could be used in medical practice.

Association of the G894T polymorphism of the endothelial nitric oxide synthase gene with diabetic foot syndrome foot ulcer, diabetic complications, and comorbid vascular diseases: a Turkish case-control study.

CONTEXT: There are controversial results and insufficient knowledge in the literature about the genetics of diabetes mellitus complications in the Turkish population and endothelial nitric oxide synthase (eNOS) gene polymorphisms may act as a potential modifier of diabetic vascular complications. OBJECTIVE: The objective of this study was to determine the association between eNOS G894T polymorphisms and diabetes-related diseases. DESIGN: A Turkish case-control study was designed. SETTING: The study was carried out in the Ankara University Hospital. PATIENTS OR OTHER PARTICIPANTS: Totally, 97 Turkish patients with diabetic foot ulcers and 102 controls were enrolled. Patients who had not received antimicrobial treatment in the preceding 6 months were included. Diabetic patients with hand and/or foot ulcers resulting from major trauma, such as road traffic accidents, were excluded. MAIN OUTCOME MEASURE: The effect of eNOS gene polymorphisms on diabetic complications and comorbid diseases was measured. RESULTS: Regarding eNOS G894T gene polymorphisms, 47.4% of the patients had GG (n = 46), 47.4% (n = 46) had GT, and 5.2% (n = 5) had TT alleles in the diabetes mellitus group, and 47.0% (n = 48), 41.2% (n = 42), and 11.8% (n = 12) had GG, GT, and TT alleles in the control group, respectively. There was no significant difference between the groups regarding the eNOS G894T gene allele ratios. Between groups with and without diabetic complications, a significant difference has only been found in the distribution of alleles in patients with comorbid atherosclerotic heart disease, whose GT-TT alleles were significantly higher than the GG alleles (p = 0.004). CONCLUSION: G894T polymorphism of eNOS gene was not associated with foot ulcer and diabetic complications, except in the presence of atherosclerotic heart disease.