Primary hypothyroidism. Differentiation from primary hypopituitarism.

Five patients with growth failure but few other abnormal clinical signs are presented. Two were shown to have primary hypopituitarism, three had primary hypothyroidism. All received levothyroxine sodium and grew 7.0 to 12.5 cm during the first year and 6.2 to 8.7 cm during the second year of treatment. Three of the adolescent patients developed signs of signs of puberty within six to nine months of initiation of levothyroxine therapy. One hypopituitary patient had femoral epiphysial dysgenesis, hypopglycemia, and undescended testes. One hypothyroid patient had been treated for diabetes mellitus for 8.5 years and may be the youngest patient reported with such a disease combination. We conclude that in a few patients with growth failure without specific clinical signs, diagnosis and differentiation between primary hypothyroidism and primary hypopituitarism can only be made by specific endocrinologic testing.