Alkaptonuric ochronosis and multiple intracranial aneurysms.

Alkaptonuric ochronosis is a heritable disorder of tyrosine metabolism, with various systemic abnormalities related to pigment deposition and degeneration of collagen and other tissues, including the heart and aorta, though no cerebrovascular abnormalities have been reported. The authors report a patient with alkaptonuric ochronosis and multiple intracranial aneurysms presenting with subarachnoid hemorrhage. The ruptured aneurysm was surgically treated, with a satisfactory outcome. In view of the well-known association of other connective tissue disorders with intracranial aneurysms, a potentially causal relationship is suggested between cerebral aneurysms and alkaptonuric ochronosis.