GPT and isolated congenital growth hormone deficiency: However, more IGHD subjects (7/22) than COs (3/23) had an ALT/upper limit of normal ratio above one (P=0.044): four IGHD subjects (1.04, 1.13, 1.29, and 1.87) and three COs (1.20, 1.33, and 1.42) less than twice, and three IGHD subjects more than twice (2.09, 2.20, and 2.67).