Hajdu–Cheney syndrome

The Hajdu -Cheney syndrome, also called Autosomal dominant familial acro-osteolysis or idiopathic acro-osteolysis or hereditary idiopathic osteolysis type VI, is a very rare genetic disease that leads to the local degeneration of bone tissue ( osteolysis).

Prevalence and etiology

The Hajdu -Cheney syndrome is a very rare disease. About 50 cases have been reported worldwide reported. The disease follows an autosomal dominant inheritance in general. Which gene or genes are affected thereby, as well as the molecular pathogenesis is still unclear. It is believed that sporadic cases caused by de novo mutations.

Pathogenesis

The Hajdu -Cheney syndrome manifests itself in the affected patients including by short stature, a progressive reduction of the distal phalanges (finger bones) and forced standing metacarpal bones (ossa carpal bones ). The sutures of the skull ( suture ) does not ossify. The frontal sinus (sinus frontalis) is missing and the Turkish saddle ( sella turcica ) is extended. With the progression of the disease can result in compression of the basilar artery, which can be life-threatening. The ears with large earlobes, sit deeper than normal. The nose falls out wide. The degradation of the alveolar ( alveolar process ) leads to an early loss of teeth. The loss of bone osteopenia may result in the further course of the disease to the curvature of the spine (scoliosis ). In addition to these Hauptsympotmen additional symptoms such as polycystic kidney disease, congenital heart defects, hydrocephalus ( water head '), cleft palate and hepatosplenomegaly were observed ( enlargement of liver and spleen) in some individuals. Due to the deterioration of the bones patients are physically weak and easily broken bones to pull.

Diagnosis

The first signs of the disease, which can be rarely diagnosed in childhood, are pain in the hands. A bone densitometry ( bone densitometry ) can demonstrate the extreme degradation of the bone.

Therapy

An early manifesting Osteoporosis is treatable with bisphosphonates.

First description

The U.S. radiologist William D. Cheney ( born 1918 ) described in 1965 with a family in northern Michigan for the first time the Hajdu- Cheney syndrome. A mother and her four children showed symptoms of acro-osteolysis, a variety of Wormschen bones and hypoplasia of the ascending ramus on both sides ( ramus ). Another is named after the Hungarian- British radiologist Nicholas Hajdu ( b. 1908 ) of a kranioskelettale dysplasia described in 1948.