Hajdu-Cheney syndrome is a very rare connective tissue disorder. To date, about 80 cases have been reported worldwide. Hajdu-Cheney syndrome is an autosomal dominant type of osteolytic disorders, characterized by short stature, acro-osteolysis of distal phalanges and generalized osteoporosis associated with additional ossification anomalies, craniofacial dysmorphism, dental anomalies and a wide range of other characteristics. Other symptoms may include joint laxity, premature loss of teeth, hearing loss, and a hoarse voice.
Diagnosis of Hajdu-Cheney syndrome is based on clinical and radiological examinations. There is no treatment for this syndrome, but early osteoporosis might be treated by bisphosphonates, alone or in combination with teriparatide. Mutations in the NOTCH2 gene, located on chromosome 1p12 are the cause of Hajdu-Cheney syndrome.