Dyggve-Melchior-Clausen syndrome

Affected newborns may be small at birth, but otherwise appear normal. Skeletal findings are often recognized first between 1 and 18 months. With age, other characteristics begin to develop. Chest deformities, feeding difficulties, and developmental delay usually occur before 18 months. Disproportionate short stature usually occurs after 18 months. Additional features may include a long skull, distinctive facial appearance, a protruding jaw, microcephaly, and claw-like hands. Intellectual disability occurs in most cases, ranging from moderate to severe.^[1]

Affected individuals can also develop a protruding breastbone; spinal abnormalities; abnormal bones in the hands, fingers, toes, wrists, and long bones of the arms and legs; and joint contractures, especially of the elbows and hips. Secondary problems resulting from the skeletal abnormalities may include spinal compression, dislocated hips, and restricted joint mobility. These problems may in turn cause a waddling gait.^[1]

DMC syndrome may be suspected following a thorough clinical evaluation, a detailed patient history, and identification of characteristic findings (e.g., barrel chest, and disproportionate short stature). Radiographs may confirm specific skeletal abnormalities and findings consistent with DMC syndrome. Genetic testing can also confirm a diagnosis.^[1]

GeneTests lists the name of the laboratory that performs clinical genetic testing for Dyggve-Melchior-Clausen syndrome. To view the contact information for this laboratory, click here.

Please note:  Most of the laboratories listed through GeneTests do not accept direct contact from patients and their families; therefore, if you are interested in learning more, you will need to work with a health care provider or a genetics professional.  Below, we provide a list of online resources that can assist you in locating a genetics professional near you.

Treatment of individuals with DMC syndrome depends on the affected person's symptoms and is usually supportive. There is no cure for this condition. Treatments might include spinal fusion of the segments of the spinal column at the top of the spine or other means of vertebral stabilization. Additional surgical techniques may be used to correct various skeletal abnormalities such as dislocation of the shoulder and hip joints. In some cases, hip replacement is required. Children with DMC syndrome may benefit from early intervention and special educational programs.^[1]

DMC syndrome is a progressive condition, meaning that signs and symptoms worsen over time. The orthopedic complications usually progress, which can include lumbar lordosis, thoracic kyphosis, scoliosis, dislocation in the hip joints, deformed knees, and spinal cord compression.^[1][3] Adult height is severely reduced with height ranging from 82 cm to 128 cm (32 in to 50 in). Neurological complications may include hyperactivity, autistic-like behavior, lack of speech, and mild to severe intellectual disability.^[1]