Central hypoventilation with PHOX2B expansion mutation presenting in adulthood

Area of Science:

• * Genetics and Molecular Biology
• * Respiratory Medicine
• * Neurology

Background:

• * Congenital central hypoventilation syndrome (CCHS) is a rare disorder typically diagnosed in neonates, characterized by sleep-related hypoventilation.
• * CCHS is primarily caused by mutations in the PHOX2B gene, which plays a crucial role in the development of the autonomic nervous system.
• * While most cases present in infancy, late-onset CCHS has been reported, though less commonly.

Observation:

• * This report details the case of an adult patient experiencing chronic respiratory failure.
• * The patient's condition was diagnosed as CCHS associated with a PHOX2B gene mutation.
• * A key clinical observation was the patient's significantly impaired response to hypercapnia (elevated carbon dioxide levels).

Findings:

• * The study confirms that PHOX2B gene mutations can lead to CCHS presenting in adulthood.
• * The findings highlight a severe impairment in the physiological response to hypercapnia in this adult CCHS case.
• * This case expands the known clinical spectrum of PHOX2B-associated CCHS beyond early-onset presentations.

Implications:

• * The findings underscore the importance of considering CCHS in adults with unexplained chronic respiratory failure, particularly those with PHOX2B mutations.
• * Understanding the impaired hypercapnic response in adult CCHS is crucial for developing targeted management strategies.
• * This case contributes to the broader understanding of autonomic nervous system development disorders and their long-term clinical consequences.