Primary hyperparathyroidism, hypercalcemia, paranoid delusions, homicide, and attempted murder

This report describes a case of primary hyperparathyroidism in a 68-year-old man. The endocrine disorder, while suspected before the commission of homicide and attempted murder, was proven biochemically and histologically a number of months after the commission of the crimes. The acts of homicide and attempted murder followed the development of paranoid delusions, which rapidly resolved upon successful removal of a single cystic parathyroid gland adenoma. The unusual events that immediately followed the acts of violence indicate that the delusions occurred in a clear sensorium (absence of delirium). Psychological measures taken before and after surgery document improvement in subtle organic functioning while intelligence was unchanged. This report discusses the neuropsychiatric manifestations of hypercalcemia and reviews the literature.