Dyskeratosis congenita, also known as DKC or DC, is a rare genetic disorder that causes bone marrow failure. Individuals with this congenital disorder often present with unusual skin conditions which indicate the disease, although in some cases, the first indication of DKC is bone marrow failure. Diagnosis is confirmed with genetic testing. Treatment of dyskeratosis congenita ranges from medication to a bone marrow transplant.
This condition is extremely rare, occurring in roughly one in one million individuals. Although there appears to be no link to race or ethnicity, over 75% of the cases are male. The mutation appears on multiple genes, and researchers continue to discover connections. There appear to be three primary genetic links.
Zinsser-Cole-Engaman syndrome, also known as the X-recessive link, occurs when the disorder is passed down only on the X chromosome and therefore affects only males. Autosomal dominant cases occur when patients receive the defect from only one parent, whereas patients with an autosomal recessive form of the disease received mutations from both parents. In some cases of dyskeratosis congenita, there is no genetic link to the disease and the mutation occurs spontaneously.
If parents have the disease or are aware they are a carrier, genetic testing can be done in utero or soon after birth to determine if a child has DKC. Otherwise, diagnosis of the disease typically occurs around age 10 and is confirmed with genetic testing. Doctors may notice several cutaneous conditions such as a lacy rash on the face, neck and chest; nail abnormalities including ridges, splitting, and weakness; or leukoplakia, which are white patches that occur in the mouth or other mucosal areas. Many of these symptoms are similar to those of premature aging.
The most common symptom of dyskeratosis congenita is bone marrow failure. Bone marrow creates red blood cells, white blood cells, and platelets, and when the bone marrow fails, these cells are affected. Failure can progress as a reduction in any of these cells. If platelets are low, a condition known as thrombocytopenia, then patients will have blood clotting issues. A decrease in red blood cells, which carry oxygen and iron, causes anemia; if white blood cells are not produced, then patients lose their ability to fight off disease.
Bone marrow failure is common in 90% of DKC cases and is often treated with the use of steroids and other drugs that stimulate the production of marrow. A bone marrow transplant is the only way to cure bone marrow failure. A transplant comes with a high risk of complications, and it does not affect other problems caused by the disease.
Patients with dyskeratosis congenita often develop other medical problems as a result of their conditions. Those with DKC are at a higher risk for pulmonary fibrosis, certain cancers related to leukoplakia, skeletal disorders including scoliosis, and gastrointestinal problems such as cirrhosis. Life expectancy varies with the severity of the disease, but in severe cases the median life expectancy is age 16. Researchers continue to study this disease and search for treatment options.