Nijmegen breakage syndrome
What is Nijmegen Breakage Syndrome?
Nijmegen breakage syndrome (NBS) is an inherited disease in which the body’s DNA is prone to breakages. People with NBS often develop cancer at an early age and experience frequent lung and sinus infections. They also show intellectual decline, eventually leading to mild-to-moderate mental disability. People with NBS can live into adulthood, but typically not beyond their 30s or 40s.
Infants with NBS are often born with a small head size. Their physical growth is often slow, leaving them smaller than average for their age. They have characteristic features, including a sloping forehead, small chin, big ears, and prominent nose, which become more apparent later in childhood.
In one study, 35% of the 70 people studied who had NBS developed cancer—most commonly a type known as B-cell lymphoma—between the ages of 1 and 34. People with NBS cannot tolerate the high doses of ionizing radiation often used to treat cancer, and must find alternate treatment methods.
Immunodeficiency—the reduced ability of the body to fight off infection—is another symptom frequently associated with NBS. As a result, the disease causes frequent infections in the lungs, ears, sinuses, and urinary tract. Recurrent bronchitis can be life-threatening.
Intellect appears to develop normally or near-normally in early childhood, but typically declines until the person reaches mild-to-moderate levels of mental disability around the age of 10.
Carriers of NBS do not show symptoms of the disease, however recent studies have shown that some carriers may be at a greater than average risk of developing cancer.
How common is Nijmegen Breakage Syndrome?
Scientists estimate that 1 in 100,000 births is affected by NBS. The disease is most common in people of Eastern European or Slavic background, specifically those from Poland, the Czech Republic, and the Ukraine. There the carrier frequency may reach as high as 1 in 155. More than 40 cases of NBS have been diagnosed in North America.
How is Nijmegen Breakage Syndrome treated?
There is no treatment to address the underlying cause of NBS, but certain symptoms can be treated.
Vitamin E and folic acid supplements may be helpful. In some people, intravenous infusions with immunoglobulin may help reduce infections. Preventative antibiotics are another option for treating infection. Special education and speech therapy can be helpful as well.
Large doses of radiation must be avoided in people with NBS, even before birth. Cancer treatments therefore must be adapted.
What is the prognosis for a person with Nijmegen Breakage Syndrome?
Some people with NBS do live into adulthood, though typically the lifespan does not extend beyond one's 30s or 40s. The longest known lifespan of a person with NBS is 53. Cancer is the most common cause of death among people with NBS, followed by lung infections leading to respiratory failure.