Adenosine Deaminase Deficiency (ADA) - Patients can develop a number of skeletal abnormalities including prominent costochondral junctions (rachitic rosary), flaring of the anterior rib ends, pelvic dysplasia, squared off inferior scapula, or flattened vertebral bodies (platyspondyly). Patients receiving PEG-ADA therapy do not exhibit these abnormalities.
Cartilage Hair Hypoplasia - Patients may develop metaphyseal dysplasia (scalloped, flared, and sclerotic metaphyses) of the lower extremities. Additional musculoskeletal abnormalities include short limbed dwarfism, lumbar lordosis, ligamentous laxity, and scoliosis.
Schwachman-Diamond syndrome - Patients develop bone marrow failure (with neutropenia), pancreatic insufficiency, and metaphyseal chondrodysplasia.
DIRA - 2 of 9 patients with DIRA have been reported to have metaphyseal erosions. Additional bony abnormalities in patients included widened anterior rib ends, periostal elevation, and multifocal osteomyelitis.