INTRODUCTION
Thyroid and renal function have well-documented associations. Thyroid
hormones (TH) are required for kidney growth and for development and
maintenance of water and electrolyte balance. Thyroid dysfunction
affects kidney function, and renal failure affects thyroid hormone
metabolism in the peripheries as well as the
hypothalamic-pituitary-thyroid axis (1). TH are necessary for the kidney
to complete its functional growth and for the development, preservation
and maintenance of glomerular function (2). Overt hypothyroidism in
particular has been linked to a reduction in glomerular filtration rate
(GFR) and renal blood flow (RBF) (3). Cases of acute kidney injury (AKI)
due to severe hypothyroidism have been reported in the literature.
Since AKI due to severe
hypothyroidism is rare, the number of cases is insufficient for
publication beyond case series (4). The glomerular function is more
impaired than tubular function during severe hypothyroidism. In severe
hypothyroidism, a reduction in RBF has been documented, which is most
likely due to the overall hypodynamic circulation, reduced cardiac
output due to myocardial impairment, sinus bradycardia, and the reduced
inotropy and chronotropy due to lower levels of TH (5). However, the
risk factors of AKI due to severe hypothyroidism has not been fully
elucidated. This study aimed to investigate the factors that affect the
development of AKI in patients with severe hypothyroidism.