While reading with interest the recent publication regarding thyroid dysfunction and hepatitis C in men,1 I noted a number of conundrums. First, there was no biochemical confirmation of thyroid function tests (TFTs) in the exclusion criteria other than simply excluding “patients with known thyroid disease.” Second and similarly, there were no baseline TFTs in the recruited subjects. Third, the TFT testing protocol was an additional problem. Such frequency testing in this setting depends very much on the natural history, which can vary from weeks to months and is far from being completely understood.2,3 Therefore, currently there is no definitive recommendation regarding TFTs during the treatment course.4 Without such information, the concern is the probable misclassification of destructive autoimmune (bi-phasic) type “hyperthyroidism” into the “hypothyroidism” category. This point is best highlighted by the following clinical vignette.
Tran HA. The Uncertain Natural History of Thyrotoxic Patients Treated With Combination Interferon Alfa-2β and Ribavirin. Arch Intern Med. 2005;165(9):1072. doi:10.1001/archinte.165.9.1072-a