Congenital Central Hypoventilation Syndrome
What is CCHS?
CCHS is a multisystem disorder of the central nervous system where, most dramatically, the automatic control of breathing is absent or impaired. A CCHS patient’s respiratory response to low blood oxygen saturation (hypoxia) or to CO2 retention (hypercapnia) is sluggish during awake hours and absent to varying degrees during sleep, serious illness, and/or stress.
CCHS Research In 2003 independent research efforts in France, the US and Italy confirmed the key role of a de novo mutation of the PHOX2B gene in over 90% of CCHS cases. But the “size” of that mutation varies among CCHS patients, ranging from 20/25 to 20/33. Studies confirm that there is a wide range of affectedness in CCHS and suggest that there may be other candidate genes for explaining CCHS. Research confirms that each child of a CCHS patient has a 50% chance of also having CCHS. Since 2003, a blood test for the PHOX2B mutation has been available – see the Diagnostics page. For a discussion of the genetics involved in the phox2b mutation see an explanation >here. written for us by Melinda Riccitelli, CCHS mom and Professor of Biology at Mira Costa College
While most CCHS patients breathe adequately, though shallowly, while awake, observation of their respiratory status is required for optimal outcome and mechanical ventilation is required for sleep, illness or other periods of low blood oxygenation. O2 and CO2 monitoring during sleep is optimal. Studies suggest that up to 17% of CCHS children may require 24-hour ventilation support. These patients can benefit from phrenic nerve pacing during the day and alternative ventilation support overnight.
One study (2004) of 196 CCHS patients found that about 16% of CCHS patients also suffered from Hirschsprungs Disease and 18% reported gastro-esophageal reflux. A range of ophthalmologic and cardiac issues were reported in 46% and 19% of CCHS patients respectively. Patients also reported seizures (42%), recurrent pneumonia (41%), developmental delays (45%), learning disabilities (30%), fainting episodes (25%) and irregularities of body temperature control (43%). Thus, significant numbers of CCHS patients report being affected by a range of accompanying medical issues (Vanderlaan, et. al., Pediatric Pulmonology 37: 217-229, 2004).
Success in Care at Home While these health issues initially appear daunting, with appropriate home care, family support and careful medical supervision, CCHS children can lead fulfilling and productive, near-normal lives. The study cited above found that over 60% of the children were making normal progress in school, while another group required some or significant special educational support. With advances in home health care technology, such as portable ventilators, oximeters and ETCO2 monitors, has come optimal health management and much-improved prognoses for the infants diagnosed with CCHS. (On topics such as schooling, nursing support, annual testing and medical care, see this study and other reading cited on the Literature page.) The oldest CCHS patients today are in their 30s and 40s—CCHS young adults are in college, in the workplace, and some are having their own families.
Key to the CCHS patient’s longevity is informed medical supervision by medical professionals who also work to support the family in optimizing the home healthcare and school or work settings. This team approach has translated into good outcomes for the great majority of CCHS families.
