Kocher-Debre-Semelaigne syndrome.

A 4-year-old male child presented with severe growth failure and developmental delay. He had hypertrophy of calf muscles and the thyroid profile showed low levels of T3, T4 and markedly elevated level of thyroid-stimulating hormone thus confirming the presence of hypothyroidism. This combination of hypothyroidism and hypertrophy of muscles is classically described as Kocher-Debré-Semelaigne syndrome. This child was started on 50 µg of levothyroxine.