Congenital Central Hypoventilation Syndrome
Also known as: CCHS, Ondine's Curse, Primary Alveolar Hypoventilation of Childhood
Congenital Central Hypoventilation Syndrome (CCHS) is a rare, lifelong disorder affecting the autonomic nervous system, primarily impacting respiratory control. Individuals with CCHS have a reduced or absent ventilatory response to hypercapnia (increased carbon dioxide) and hypoxemia (decreased oxygen) and may require lifelong ventilatory support, especially during sleep. The condition is often associated with mutations in the PHOX2B gene.
Imagine your body sometimes forgets to breathe, especially when you're sleeping. CCHS is when that happens because a part of your brain that controls breathing isn't working right. Doctors help by giving you a machine to help you breathe.
Signs & Symptoms
- Hypoventilation (especially during sleep)
- Cyanosis (bluish discoloration of the skin due to low oxygen levels)
- Sleep apnea
- Bradycardia (slow heart rate)
- Hirschsprung's disease (in some cases)
- Autonomic dysfunction (e.g., altered pupillary response, sweating abnormalities)
- Tumors of neural crest origin (e.g., neuroblastoma, ganglioneuroma) in a small percentage of cases
Treatment Options
Mechanical Ventilation (Tracheostomy or Non-Invasive)
HIGHLY EFFECTIVEDiaphragm Pacing (Phrenic Nerve Stimulation)
MODERATELY EFFECTIVEMedications to manage associated conditions (e.g., bradycardia)
SUPPORTIVEGene Therapy (Experimental)
EXPERIMENTALDiagnosis
- Clinical evaluation and observation of hypoventilation
- Polysomnography (sleep study) to assess respiratory patterns during sleep
- Arterial blood gas analysis to measure oxygen and carbon dioxide levels
- Genetic testing for PHOX2B mutations
- Autonomic function testing
- Evaluation for Hirschsprung's disease
History
CCHS was first described in the medical literature in the 1970s. The association with PHOX2B mutations was discovered in 2003, marking a significant advancement in understanding the genetic basis of the disease.
Recent Breakthroughs
Novel PHOX2B Mutation Identified in CCHS Patient
Researchers identified a new mutation in the PHOX2B gene in a patient with atypical CCHS, expanding the known spectrum of genetic variants associated with the condition.
Improved Diaphragm Pacing Techniques for CCHS
A study demonstrated improved outcomes with refined diaphragm pacing techniques, leading to reduced reliance on mechanical ventilation in some CCHS patients.