skip to main content

Nephrotic Syndrome Hypothyroidism — ESENeph MCQ

Instant feedback + full explanation. One question, done properly.

ModerateGlomerulonephritisNephrotic Syndrome HypothyroidismESENeph

A 42-year-old man with nephrotic syndrome and CKD G3a has hypothyroidism (TSH 18 mU/L, free T4 9 pmol/L). He was not known to be hypothyroid before developing nephrotic syndrome. What is the most likely mechanism?

Educational content. Not a substitute for clinical judgement or local policy.

Reveal the answer and explanation

Correct answer: C — Urinary loss of thyroid-binding globulin (TBG) and thyroxine in nephrotic-range proteinuria

Nephrotic syndrome causes urinary losses of thyroid-binding globulin (TBG) and protein-bound thyroxine (T4), leading to hypothyroidism or worsening of subclinical hypothyroidism. This is a well-recognised but often overlooked complication. TSH should be checked in all patients with significant nephrotic syndrome. Treatment is with Levothyroxine, but higher doses may be needed due to ongoing urinary T4 losses (up to 50-100% higher than standard replacement). As nephrotic syndrome remits, the Levothyroxine dose should be reassessed to avoid iatrogenic thyrotoxicosis.

Reference: KDIGO 2021 – GN Guideline (Chapter 1: Complications); Feinstein et al 1982