About CACP Syndrome
The New York Center for Rare Diseases supports the mission and guidelines of the Genetic and Rare Diseases Information Center (GARD). The following information is provided by the NIH.
Summary
Camptodactyly-arthropathy-coxa vara-pericarditis syndrome (CACP) is a rare condition which causes joint abnormalities. The name comes from the main symptoms, including permanent bending of the fingers (camptodactyly), joint disease (arthropathy), and changes in the hip joint resulting in shortened legs and a possible limp (coxa vara). Some people with CACP also have too many cells between their joints (synovial hyperplasia) and too much fluid around the heart (pericardial effusion) or lungs (pleural effusion). Camptodactyly-arthropathy-coxa vara-pericarditis syndrome is caused by a genetic change in the PRG4 gene. This gene is responsible for making a protein that lubricates the joints. The condition is inherited in an autosomal recessive manner. CACP may be at first confused with juvenile idiopathic arthritis because the two diseases have similar symptoms. Diagnosis is based on clinical findings (symptoms which the doctor notices on a physical exam) and a biopsy of the fluid between the joints (synovial fluid). Genetic testing can confirm the diagnosis.
Causes
What Causes This Disease?
Genetic Mutations: Camptodactyly-arthropathy-coxa vara-pericarditis syndrome is caused by genetic mutations, also known as pathogenic variants. Genetic mutations can be hereditary, when parents pass them down to their children, or they may occur randomly when cells are dividing. Genetic mutations may also result from contracted viruses, environmental factors, such as UV radiation from sunlight exposure, or a combination of any of these.
If you suspect you may have this disease, you may want to start collecting your family health history. Information such as other family members who have had similar symptoms, when their/your symptoms first appeared, or exposures to any potential disease-causing environmental factors should be discussed with your medical team.
Known Genetic Mutations: Camptodactyly-arthropathy-coxa vara-pericarditis syndrome is caused by genetic mutations in the following known gene(s):
PRG4
Given these known genetic mutation(s), you may want to ask your health care team if genetic testing is right for you. Genetic tests are laboratory tests that use samples of blood, saliva, or other tissues to help identify changes in genes, chromosomes, or proteins. Genetic testing can help confirm or rule out a suspected genetic disease, or can provide other useful information to your health care team.