Iatrogenic Hypothyroidism
Excessive treatment leading to iatrogenic hypothyroidism should be avoided as iatrogenic hypothyroidism can contribute to development of azotemia and shorten survival of azotemic cats (Williams et al.
2010). However, diagnosis of iatrogenic hypothyroidism is not always straightforward in cats. Cats affected present lethargy, anorexia, weight gain, and dermatologic signs. A decrease in TT4 is not specific. Therefore, measurement of an increased TSH (with canine kit) can help confirming the diagnosis (Aldridge et al., 2015).In conclusion, early detection is important and in most cats, diagnosis can be confirmed with TT4 measurement. Treatment with anti-thyroid drugs or diet is the cornerstone of medical management (either short term or long term). While monitoring TT4 is essential to detect under-treatment, overtreatment should be avoided too. Radioactive iodine therapy is the treatment of choice in many cats as it addresses the underlying disease and is noninvasive.
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