Severe Hypothyroidism Masquerading As Renal Impairment

Although subclinical primary hypothyroidism was common in patients with chronic kidney disease, renal impairment resulting from hypothyroidism was a rare occurrence. We described a 33-year-old young man who presented with rapid deterioration of renal function. He stated a two-week history of sudden onset of periorbital, facial and generalized leg swelling. Low-grade proteinuria was noted. There were no imminent symptoms suggestive of severe thyroid dysfunction. Discrepancy between the biopsy report and the clinical picture led to the assessment of thyroid function. Severe hypothyroidism with a low a free thyroxine (FT4) concentration (0.9 pmnol/L) and an elevated thyroid stimulating hormone (TSH) concentration (237 aU/mi) were found. Treatment of hypothyroid status resulted in a significant and sustained reduction of his serum creatinine level. Deficiency of thyroid hormones had been shown to reduce glomerular filtration rate (GFR) and its pathomechanism is multifactorial. Since the clinical manifestations may be subtle or avsent in most cases of hypothyroidism, we recommended that thyroid status should he assessed in patients with renal impairment of unknown cause.