Summary

We describe two cases in which the initial finding of renal impairment guided further investigation leading to the diagnosis of hypothyroidism. In the first case, a 40-year-old female patient presented with a complaint of facial puffiness. On investigation, her serum creatinine was 1.86 mg/dl, glomerular filteration rate (GFR) by Cockcroft-Gault equation was 40 ml/min, free throxine (FT4) was <1 mg/dl and a thyroid stimulating hormone (TSH) concentration >80 μ/l. In the second case, a 45-year-old male patient presented with complains of indigestion, weight gain and lethargy. On examination, his blood pressure was 160/100 mm Hg and there was facial puffiness and mild pedal oedema. On investigation, her serum creatinine was 1.5 mg/dl and estimated GFR by Cockcroft-Gault equation was 55 ml/min. Thyroid function was abnormal, FT4 2.99 mg/dl and TSH 80 μ/l. In both the cases, thyroid hormone replacement therapy brought about complete recovery of renal function.