Staying alert with polyhydramnios; an Ondine syndrome case

Area of Science:

• Medical Genetics
• Neonatology
• Perinatology

Background:

• Severe polyhydramnios and fetal growth restriction can indicate underlying fetal disorders.
• Congenital central hypoventilation syndrome (CCHS), a rare genetic disorder caused by PHOX2B gene mutations, is a critical consideration in such cases.
• CCHS affects approximately 1 in 200,000 live births, and intrauterine findings have not been previously documented.

Purpose of the Study:

• To report the intrauterine findings in a case of congenital central hypoventilation syndrome (CCHS).
• To emphasize the importance of considering CCHS in pregnancies with severe polyhydramnios and fetal growth restriction.
• To highlight the potential for early intrauterine diagnosis and therapeutic interventions.

Main Methods:

• A case presentation of a pregnant patient with severe polyhydramnios and a small-for-gestation fetus.
• Third-trimester ultrasound (US) evaluation.
• Postnatal assessment of the newborn, including blood gas analysis and genetic testing for PHOX2B variants.

Main Results:

• The newborn exhibited recurrent apneas, cyanosis, and respiratory acidosis, necessitating neonatal intensive care.
• Standard imaging and functional tests in the newborn were normal.
• A de novo pathogenic PHOX2B variant was identified, confirming the diagnosis of CCHS.

Conclusions:

• Early identification of CCHS through intrauterine findings is crucial for timely intervention.
• Multidisciplinary care is essential for managing CCHS and preventing long-term complications.
• Prompt diagnosis and management can lead to favorable outcomes despite the high mortality associated with CCHS.