Isolated central hypothyroidism: Underlying pathophysiology and relation to antidepressant and antipsychotic medications-A multi-centre South Wales study.

OBJECTIVE: Isolated biochemical central hypothyroidism is a presentation we are experiencing more frequently as endocrinologists, with variation in levels of investigation between physicians. We therefore conducted research to investigate the final diagnosis and clinical outcome of patients across multiple hospitals in South Wales with biochemical isolated central hypothyroidism; namely to establish whether this isolated biochemical picture was clinically significant. We also analysed whether there is an association between this biochemical picture and treatment with antidepressant and antipsychotic medications, and how common this is. DESIGN: We performed a retrospective observational study of patients across nine different hospitals in South Wales. We analysed patients referred to endocrinology at each site over a 6-year period with unexplained isolated biochemical central hypothyroidism. MATERIALS AND METHODOLOGY: 1022 individual patients' thyroid function test results were identified from our biochemical database using our inclusion criteria. After exclusion criteria were applied, 71 patients' results were analysed as to the final pathophysiology of their central hypothyroidism. RESULT: Of the 71 patients included in the study, none were found to have any clinically significant pathology on pituitary imaging. On reviewing their medications, 46/71 (65%) were found to be taking psychotropic medications. CONCLUSIONS: Our study strongly suggests isolated central hypothyroidism, in the absence of other pituitary hormone dysfunction or visual field defect, does not require further investigation, saving resources as well as sparing patients unnecessary anxiety. It also strongly supports a relationship between patients taking psychotropic medications and biochemical isolated central hypothyroidism, an association only described in a very limited amount of literature before this, and further supporting our previous single-centre study findings. The mechanism behind this is likely to be the suppression of thyrotropin secretion via antagonism of the dopamine-serotoninergic pathway. In our opinion, patients found to have isolated biochemical central hypothyroidism who are taking psychotropic medications can therefore be regarded to have a recognised cause for this biochemical finding and do not require further radiological investigation.

Colchicine overdose: A South African experience, a case report.

INTRODUCTION: Colchicine overdose is uncommon but is associated with a high mortality rate. It has a narrow therapeutic index and has been described to have a 100% mortality with ingestion of >0.8 mg/kg (Finkelstein et al., 2010; Herran-Monge et al., 2013; Aghabiklooei et al., 2014; Erden et al., 2013). CASE REPORT: This is a case report of a 19-year-old male who ingested 0.4 mg/kg of colchicine in a suicide attempt. He developed multiorgan dysfunction. He was managed supportively, and the dysfunction resolved. DISCUSSION: The clinical presentation and management should be familiar to all those who work in acute care in order to be able to identify and treat it timeously thus preventing morbidity and mortality. Treatment is largely supportive. To the best of our knowledge this is the first case of colchicine overdose described in Sub-Saharan Africa.