Corticotropin Deficiency in Russell-Silver Syndrome-Reply

In Reply.—Drs Morris and Reiter have stated their concern that corticotropin deficiency may have been inadequately documented in a child with Russell-Silver syndrome and hypopituitarism.¹ A prolonged metyrapone test was performed according to the method of Limal et al,² in which metyrapone was administered orally every four hours for six doses; serum for cortisol and 11-desoxycortisol measurements was obtained at 8 AM, four hours after the last dose.² The postmetyrapone serum 11-desoxycortisol level was 3.3 μg/dL (0.096 μmol/L) in our patient, compared with a range of 12.5 to 28.2 μg/dL (0.363 to 0.819 μmol/L) in control subjects, while the serum cortisol level was 9 μg/dL (250 nmol/L), compared with 1.9 to 6.0 μg/dL (50 to 160 nmol/L). In the face of well-documented growth hormone and thyrotropin deficiencies, the history of recurrent episodes of prostration, and the toleration of all doses of metyrapone, the test was interpreted