The effects of thyroid metabolism on renal function in children are barely referred to in the literature. Primary hypothyroidism is known to be associated with a consistent elevation in serum creatinine levels. This is essentially because of the hypodynamic state that occurs in hypothyroidism, leading to a reduced glomerular filtration rate and hypercreatinemia. A teenager who developed renal failure due to primary hypothyroidism is reported. He displayed diverse serum biochemistry anomalies with an unremarkable physical examination. Thyroxine replacement therapy completely restored the euthyroid state and renal function. We propose, in accordance with other authors, measurement of thyrotropin levels in patients with hypercreatinemia.