Known as Ondines curse, Central hypoventilation syndrome (CHS) is a respiratory disorder that results in respiratory arrest during sleep. CHS can either be congenital (CCHS) or acquired (ACHS) later in life. It is fatal if left untreated.
What causes central hypoventilation syndrome?
Congenital central hypoventilation syndrome (CCHS) is a disorder of the autonomic nervous system that affects breathing. It causes a person to hypoventilate (especially during sleep), resulting in a shortage of oxygen and a buildup of carbon dioxide in the blood.
What are the types of central hypoventilation syndrome?
It have two forms of presentation, a classic form that usually begin shortly after birth in newborns, and a milder later-onset presentaition in toddlers, children and adults.
How does central hypoventilation syndrome present?
Affected infants hypoventilate upon falling asleep and exhibit a bluish appearance of the skin or lips (cyanosis).
What are the symptoms of central hypoventilation syndrome?
In addition to cyanosis, other symptoms may include difficulty regulating heart rate and blood pressure; decreased perception of pain; low body temperature; sporadic profuse sweating; Hirschsprung disease; constipation; learning difficulties; eye abnormalities; and a characteristic facial appearance with a short, wide, somewhat flattened face.
What is the association between central hypoventilation syndrome and rare tumors?
People affected with central hypoventilation syndrome can also have tumors of neural crest origin, such as neuroblastoma, ganglioneuroblastoma, and ganglioneuroma. The later-onset form is milder, and some cases may present as infants and children who die suddenly and unexpectedly (“SIDS” and “sudden unexplained death of childhood”).
What causes central hypoventilation syndrome?
CCHS is caused by a variation (mutation) in the PHOX2B gene.
How is central hypoventilation syndrome inherited?
Caused by a mutation in the PHOX2B gene, it is inherited in an autosomal dominant manner. However, over 90% of cases are due to a new mutation in the affected person and are not inherited from a parent.
How is central hypoventilation syndrome diagnosed?
Diagnosis is made with the clinical symptoms and the genetic test showing the variation in the PHOX2B gene.
How is central hypoventilation syndrome treated?
Treatment typically includes mechanical ventilation or use of a diaphragm pacemaker.
What is the prognosis for people with central hypoventilation syndrome?
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.
How is CCHS inherited?
Congenital central hypoventilation syndrome (CCHS) is inherited in an autosomal dominant manner. This means that having a change (mutation) in only one copy of the responsible gene in each cell is enough to cause features of the condition.
Can one get CCHS even if their parents did not have the disease?
Yes. The genetics of CCHS can be complex. Most people with CCHS have a new (de novo) mutation in the responsible gene (the PHOX2B gene). De novo mutations occur for the first time in the affected person and are not inherited from a parent. Some people with CCHS have a parent with the condition, and inherit the mutation from that parent.
What is germline mutation and how does that affect CCHS?
In some cases, an asymptomatic parent of a person with symptoms has a PHOX2B mutation in some of their germ cells (egg or sperm cells, not body cells). This is called germline mosaicism. Some of these parents also have a PHOX2B mutation in some of their body cells. This is called somatic mosaicism. Germline mosaicism with or without somatic mosaicism is present in about 25% of asymptomatic parents of people with CCHS.
How do you screen for CCHS genetically?
Parents with mosaicism should have a comprehensive assessment to determine if any features of CCHS are present. It is also recommended that parents of a person with a presumed de novo mutation have genetic testing for the presence of the mutation, including testing that detects mosaicism at low levels.
How can W8MD help?
our Seep Medicine Program uses state of the art technology including the convenient home sleep studies or in lab sleep diagnostic studies to diagnose and treat over 80 different sleep disorders including CCHS, sleep apnea, narcolepsy, restless leg syndrome, insomnia and other sleep disorders with board certified physicians.