Creutzfeldt-Jakob disease (CJD) has been reported in three US patients previously treated with human growth hormone derived from large pools of human cadaver pituitary glands (pit-hGH). Neurologic disorders other than CJD occurred in 10 growth hormone-deficient patients treated with pit-hGH. These 10 cases could have been chance events or true syndromes; some cases may have been caused by transmissible agents contained in the pooled growth hormone product.