Effects of thyroid hormone replacement on glycated hemoglobin levels in non diabetic subjects with overt hypothyroidism

Objective Glycated hemoglobin (HbA1c) may not accurately reflect the level of glycemia in conditions of altered erythrocyte turnover. Hypothyroidism is one condition associated with sluggish erythropoesis. To assess changes in HbA1c, independent of changes in plasma glucose after initiation of thyroxine replacement in patients with overt hypothyroidism. Materials and methods In this prospective longitudinal study carried out in a tertiary care centre, adult non-diabetic patients with overt hypothyroidism recruited between March 2012 to August 2013 were rendered euthyroid on thyroxine. They underwent testing for hemoglobin, HbA1c, reticulocyte count, thyroxine, thyrotropin and a standard oral glucose tolerance test, both before and at 3 months after restoration to the euthyroid state. Main outcome assessed was the change in HbA1c independent of the change in glucose parameters. Results Thirty eight patients (35 female and 3 male) aged 37.8 ± 10.2 years with overt hypothyroidism (thyroxine 12.6 ± 13.4 ng/mL and thyrotropin -98.1 ± 63.7 µIU/mL respectively) were recruited. While HbA1c fell from 5.8 ± 0.7% to 5.6 ± 0.5% (p = 0.009) at 3 months following the correction of hypothyroidism, there were no changes in the fasting and the 2 hr post oral glucose tolerance test glucose (p = 0.67 and 0.56 respectively). The number of patients with dysglycemia diagnosed by HbA1c (i.e HbA1c≥ 5.7%) fell from 25 (65.78%) to 17 (44.7%) after treatment (p = 0.008). There were 7 (18.4%) patients with HbA1c ≥ 6.5% at baseline, but this fell to just 4 (10.5%) (p < 0.001) after 3 months of euthyroidism. Conclusion HbA1c is not a reliable diagnostic test for diabetes in the presence of hypothyroidism.

Novel three missense mutations observed in Von Hippel-Lindau gene in a patient reported with renal cell carcinoma.

Von Hippel‑Lindau (VHL) disease is an autosomal dominant hereditary cancer syndrome that predisposes to the development of a variety of benign and malignant tumors, especially cerebellar hemangioblastomas, retinal angiomas and clear‑cell renal cell carcinomas (RCC). We have identified of VHL gene using immunohistochemistry in a patient who was diagnosed for RCC. In order to understand the involvement of mutation in the VHL gene exon 1 was amplified and sequenced (accession number: JX 401534). The sequence analysis revealed the presence of novel missense mutations c.194 C>T, c.239 G>A, c.278 G>A, c.319 C>G, c. 337 C > G leading to the following variations p.Ala 65 Val, p.Gly 80 Asp, p.Gly 93 Glu, p.Gln 107 Glu, p.Gln 113 Glu in the protein.