CHAR syndrome is a rare, genetic disorder characterized by a specific set of birth defects, most notably affecting the heart and face. It stands for Cardiac defects (specifically Patent Ductus Arteriosus), Head and facial abnormalities, Abnormalities of the nose, and Retardation of growth.
Key Features of CHAR Syndrome:
Cardiac Defect: Patent Ductus Arteriosus (PDA)
- The most common and characteristic feature of CHAR syndrome is a patent ductus arteriosus (PDA). This means that the ductus arteriosus, a blood vessel connecting the aorta and pulmonary artery that is supposed to close shortly after birth, remains open. This can lead to heart strain and other complications.
Facial Features: Distinctive Facial Dysmorphism
Babies with CHAR syndrome typically present with recognizable facial features, including:
- Wide-set eyes (Hypertelorism): The eyes are spaced further apart than usual.
- Downslanting palpebral fissures: The opening between the eyelids slopes downwards.
- Mild ptosis: Drooping of the upper eyelids.
- Flat midface: The middle portion of the face appears flattened.
- Flat nasal bridge and upturned nasal tip: The bridge of the nose is flat, and the tip of the nose points upwards.
- Short philtrum with a triangular mouth: The philtrum (the vertical groove between the nose and upper lip) is short, and the mouth may appear triangular in shape.
- Thickened, everted lower lip: The lower lip may appear thicker than normal and turned outwards.
Nasal Abnormalities
- Nasal abnormalities, though part of the acronym, are encompassed within the facial dysmorphism. The flat nasal bridge and upturned nasal tip are key features. Nasal obstruction or choanal atresia (blockage of the nasal passages) can also occur, although less commonly.
Growth Retardation
- Individuals with CHAR syndrome may experience growth retardation, meaning they grow at a slower rate than expected. This can affect both weight and height.
Genetics and Cause:
CHAR syndrome is caused by mutations in the TFAP2B gene. This gene plays a crucial role in the development of facial structures, the heart, and other tissues during embryonic development. The condition is inherited in an autosomal dominant pattern, meaning that only one copy of the mutated gene is needed to cause the disorder.
Diagnosis and Management
Diagnosis is typically based on the presence of the characteristic clinical features (especially PDA and facial dysmorphism) and can be confirmed by genetic testing to identify mutations in the TFAP2B gene.
Management focuses on addressing the specific symptoms and complications:
- PDA Closure: The PDA may require medical management (medications) or surgical closure.
- Growth Monitoring: Monitoring growth and providing nutritional support if needed.
- Facial Reconstruction: Surgical procedures might be considered to address certain facial features.
- Developmental Support: Early intervention and support to address any developmental delays.
