ABSTRACT
A seven-months-old girl under treatment for pneumonia presented with generalized edema, decreased urinary output and was found to have hypertension, muco-cutaneous fungal infection and pulmonary hypertension. Investigations revealed that she had heavy proteinuria, hypertriglyceridemia, hypoalbuminemia and elevated levels of free T3 and T4 with suppression of TSH levels in the serum. A diagnosis of autoimmune thyroiditis (AT) in thyrotoxic phase was made on the basis of clinical presentation and presence of anti-TPO antibodies and reduced uptake in thyroid (technetium) scintigraphy. The child responded to carbimazole therapy and propranolol. The case is presented to remind pediatricians about the rare occurrence of auto-immune thyroiditis in infancy with rare complications such as nephrotic syndrome and pulmonary hypertension.