Both overt (OHT) and subclinical hypothyroid (SHT) disorders have been found to be associated with increased oxidative stress (OXS). Excess thyrotropin [thyroid stimulating hormone (TSH)] is known to directly produce OXS. Increased lipid peroxidation is known to facilitate protein carbonylation. However, the associations between lipid and protein oxidation and elevated TSH levels have not been studied. Thyroid profile, lipid peroxidation as malondialdehyde (MDA) levels and protein carbonylation as protein carbonyls (PCO) were estimated in OHT and SHT groups consisting of 36 patients each, in comparison to 39 euthyroid controls. We also determined the associations between TSH, MDA, and PCO levels in OHT and SHT groups. Increased oxidative damage was evidenced through significant elevations in the concentrations of MDA and PCO in OHT and SHT groups compared to controls (p < 0.01). Both TSH and MDA levels were positively associated with PCO in OHT group. Partial correlation analysis revealed that both excess TSH and increased MDA levels are mutually influencing elevated PCO. The results indicate that there is a simultaneous oxidative damage to lipids and proteins leading to increased MDA and PCO levels in both patient groups. Either of the excess TSH and increased MDA levels are combinably involved in the elevation of PCO in hypothyroidism.

Oxidative stress as a result of disequilibrium between free radical generation and antioxidant status has been implicated in several pathologies including thyroid diseases. Studies on antioxidant status in overt (OHT) and subclinical hypothyroidism (SHT) are controversial and limited. The aim of this study was to determine the effect of OHT and SHT on antioxidant status. Thirty-six patients with OHT, 36 patients with SHT, and 39 healthy euthyroid subjects as the control group were included in the study. Plasma levels of malondialdehyde (MDA), reduced glutathione (GSH) and total antioxidant capacity (TAC) as ferric reducing ability of plasma (FRAP), and erythrocyte antioxidant enzymes superoxide dismutase (SOD), glutathione peroxidase (GPx), SOD/GPx ratios, catalase (CAT), and glutathione reductase (GR) were analyzed in all groups. MDA and GPx values were elevated, while GSH, FRAP, SOD, and SOD/GPx ratio were decreased in both patient groups compared with controls. No change in activities of CAT and GR were observed in both the patient groups. Significant differences were observed between OHT and SHT groups with high MDA, GPX and low GSH, FRAP, SOD, and SOD/GPx ratio in OHT group. Thus, hypothyroid patients have a deficient antioxidant defense in the form of decreased activity of SOD, decreased levels of FRAP and GSH along with an increase in GPx activity. The severity of the disease appears to decide the degree of deficiency and our findings also point to this, in the form of decrease in SOD, FRAP, and GSH observed being more in OHT than in SHT patients. Hormonal changes and increased lipid peroxidation, which also vary with severity of disease, appear to contribute to the antioxidant deficiency.

Background:Thyroid nodules are common. They can be either benign or malignant. Solitary thyroid nodules (STN) have a high likelihood of being malignant. They should be characterized properly for optimum management.Materials and Methods:In this study, we have analyzed our departmental data over a period of 5 years. All the patients who presented to the outpatient department with a clinically detected STN were included in the study group. Our approach was individualized. Preoperative ultrasonography (USG) and fine-needle aspiration cytology were planned in all these patients. Hemi thyroidectomy and total thyroidectomy with and without neck dissection were performed wherever appropriate.Results:There were 162 cases of clinically detected STN. USG findings were available in 146 cases. Postoperative histopathology was reported as malignant in 58 cases. Malignant STN was more likely in males. Ultrasonographically detected solid STN were more prone for malignancy as compared to multinodular goiter (P = 0.000) Presence of micro calcification and cervical lymphadenopathy were more commonly noted in malignant thyroid swellings.Conclusion:Solitary thyroid nodules do have a high likelihood of harboring a malignancy. Solid echogenicity, micro calcification and cervical lymphadenopathy on USG were seen more frequently in malignant nodules.

Aim. To identify dysmorphic features and cardiac, skeletal, and urogenital anomalies in patients with congenital hypothyroidism. Patients and Methods. Seventeen children with congenital primary hypothyroidism were recruited. Cause for congenital hypothyroidism was established using ultrasound of thyroid and 99mTc radionuclide thyroid scintigraphy. Malformations were identified by clinical examination, echocardiography, X-ray of lumbar spine, and ultrasonography of abdomen. Results. Ten (59%) patients (6 males and 4 females) had congenital malformations. Two had more than one congenital malformation (both spina bifida and ostium secundum atrial septal defect). Five (29%) had cardiac malformations, of whom three had only osteum secundum atrial septal defect (ASD), one had only patent ductus arteriosus (PDA), and one patient had both ASD and PDA. Seven patients (41%) had neural tube defects in the form of spina bifida occulta. Conclusion. Our study indicates the need for routine echocardiography in all patients with congenital hypothyroidism.

Increase of MDA and IMA levels with decreased antioxidant status indicate the presence of OS in hypothyroid patients, which was more pronounced in OHT patients. Elevated levels of IMA can be a clinically useful marker of protein oxidative damage and OS in hypothyroidism.

Hypothyroidism is associated with increased oxidative stress. The mechanism underlying the endothelial dysfunction in thyroid disease is not yet clear. This study aims to investigate lipid peroxidation and its association with endothelial dysfunction in overt hypothyroidism (OHT).Plasma malondialdehyde (MDA) as a marker of oxidative stress and plasma nitrates and asymmetric dimethyl arginine levels (ADMA) as markers of endothelial dysfunction were estimated in 25 OHT patients in comparison to 25 euthyroid controls. Plasma MDA, ADMA levels were significantly increased, whereas plasma nitrates were significantly decreased in the patient group compared to control group (p<0.01). Moreover, a significant positive association between plasma MDA and ADMA was found in the patient group (ρ=0.472, p=0.036). Our results reveal the presence of endothelial dysfunction in OHT patients as evidenced by decreased plasma nitrates and increased ADMA levels. Increased levels of MDA represent an increased generation of reactive oxygen species in these patients. A finding of significant direct relation of plasma MDA with ADMA indicates that oxidative stress has a strong impact on endothelial dysfunction in overt hypothyroidism. Further studies focusing on the role of oxidative stress in endothelial dysfunction and the effects of antioxidant supplementation on endothelial function in OHT patients are required.

Aim. To identify dysmorphic features and cardiac, skeletal, and urogenital anomalies in patients with congenital hypothyroidism. Patients and Methods. Seventeen children with congenital primary hypothyroidism were recruited. Cause for congenital hypothyroidism was established using ultrasound of thyroid and (99m)Tc radionuclide thyroid scintigraphy. Malformations were identified by clinical examination, echocardiography, X-ray of lumbar spine, and ultrasonography of abdomen. Results. Ten (59%) patients (6 males and 4 females) had congenital malformations. Two had more than one congenital malformation (both spina bifida and ostium secundum atrial septal defect). Five (29%) had cardiac malformations, of whom three had only osteum secundum atrial septal defect (ASD), one had only patent ductus arteriosus (PDA), and one patient had both ASD and PDA. Seven patients (41%) had neural tube defects in the form of spina bifida occulta. Conclusion. Our study indicates the need for routine echocardiography in all patients with congenital hypothyroidism.

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