CCHS: What makes sleep deadly in this rare disease?https://indianexpress.com/article/explained/congenital-central-hypoventilation-syndrome-what-makes-sleep-deadly-in-this-rare-disease-5540257/

CCHS: What makes sleep deadly in this rare disease?

Those suffering from the disease, called Congenital Central Hypoventilation Syndrome (CCHS), can lose their life if they fall into deep sleep. A look at how it affects the body.

Congenital Central Hypoventilation Syndrome: What makes sleep deadly in this rare disease?
Yatharth with his mother Meenakshi. (Express Photo: Anand Mohan J)

An infant under treatment at Delhi’s Sir Ganga Ram Hospital is suffering from a rare disease (The Indian Express, January 15), with less than 1,000 known cases all over the world. Those suffering from the disease, called Congenital Central Hypoventilation Syndrome (CCHS), can lose their life if they fall into deep sleep. A look at how it affects the body:

The disease

CCHS is a disorder of the nervous system in which the cue to breathe is lost when the patient goes to sleep. This results in a lack of oxygen and a build-up of carbon dioxide in the body, which can sometimes turn fatal. In babies such as Yatharth, who is admitted in Sir Ganga Ram Hospital, a typical presentation of the lack of breathing is when the lips start turning blue. This, in turn, is a typical feature of a carbon dioxide build-up, and is also seen in babies with congenital heart problems when the extremities of the body are deprived of oxygen. Though the name describes the disorder as congenital, some forms of the disease may also be present in adults. In fact, adult onset is far more common than congenital presentation; there have been many adult cases reported in medical journals over the years.
The disease is also known as Ondine’s Curse. Ondine, a nymph in French mythology, had cursed her unfaithful husband that he would forget to breathe the moment he fell asleep. He had, in happier times, pledged his love “every waking breath”.

The cause

The mutation of a gene called PHOX2B, which is crucial for the maturation of nerve cells in the body, can cause CCHS. The mutation is of a dominant trait — if just one of the gene pair changes, the effects would show. It can also be genetically acquired, which is when it is congenital. However, sudden mutation is more common than a transmission of the mutated gene from parent to child. The US National Institutes of Health (NIH) estimates that 90% of all known cases of CCHS are actually not inherited from a parent.

The symptoms

Apart from the apparent signs of oxygen deficiency, CCHS patients also have problems in regulation of heart rate and blood pressure, sweat profusely, often have constipation and cannot always feel pain. Many of them suffer from neural tumours. In some patients, there are ophthalmological symptoms. In others, there is a deficiency of the growth hormone and a propensity of the body to produce much more insulin than is normal.

Treatment

According to NIH, “Treatment typically includes mechanical ventilation or use of a diaphragm pacemaker. People who have been diagnosed as newborns and adequately ventilated throughout childhood may reach the age of 20 to 30 years, and can live independently. In the later-onset form, people who were diagnosed when they were 20 years or older have now reached the age of 30 to 55 years.”

Advertising

In Yatharth’s case, the surgery that has been prescribed proposes to put a diaphragm pacemaker that can nudge the body into remembering to breathe. It will cost Rs 38 lakh which, his patients say, they cannot afford.