Hypothalamic growth hormone deficiency and supplementary GH therapy in two patients with mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes.

Two pediatric patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes were diagnosed with growth hormone deficiency with the primary lesion identified as the growth hormone-releasing factor producing cells of the hypothalamus. Stimulation tests with insulin, levodopa and sleep did not overcome the deficient pattern of growth hormone secretion. By comparison, the growth hormone-releasing factor stimulation test generated a normal growth hormone response in these two patients. Growth hormone supplementary therapy was effective in terms of growth gain without adverse effects.