CHARGE syndrome

Synonyms

1

Overview

CHARGE syndrome, is a syndrome caused by a genetic disorder. It was first described in 1979.

In 1981, the term "CHARGE" came into use as an acronym for the set of unusual congenital features seen in a number of newborn children. The letters stand for: coloboma of the eye, heart defects, atresia of the nasal choanae, retardation of growth and/or development, genital and/or urinary abnormalities, and ear abnormalities and deafness. These features are no longer used in making a diagnosis of CHARGE syndrome, but the name remains. CHARGE syndrome is the leading cause of congenital deafblindness.

Symptoms

The acronym CHARGE was coined in 1981 to describe a cluster of features identified in a number of children. The following are the signs that were originally identified in children with this syndrome:

  • C - Coloboma of the eye, central nervous system anomalies
  • H - Heart defectsA - Atresia of the choanae
  • R - Retardation of growth and/or development
  • G - Genital and/or urinary defects (Hypogonadism)
  • E - Ear anomalies and/or deafness

The most common genital condition associated with CHARGE syndrome in boys is undescended testicles, or cryptorchidism. Another commonly associated genital condition in boys is hypospadias.

Deafness is commonly seen in CHARGE syndrome. Aside from deafness, the most common ear anomaly seen in CHARGE syndrome is the abnormal appearance of bowl-shaped and concave ears, known as "lop ears".

Causes

CHARGE syndrome is an autosomal dominant condition with genotypic heterogeneity. Most cases (58-71% in unselected CHARGE referrals and as many as 90% of patients who meet criteria for typical CHARGE syndrome) are due to mutations of the CHD7 gene leading to haploinsufficiency

Diagnosis

The diagnosis of CHARGE syndrome is often difficult, due to its rarity. This syndrome spans many disciplines, and as such, can be diagnosed by a pediatrician, oral and maxillofacial surgeon, ENT specialist, ophthalmologist, audiologist, endocrinologist, cardiologist, urologist, developmental specialist, radiologist, geneticist, physiotherapist, occupational therapist, speech therapist, or orthopedic specialist.

Signs

Although genetic testing positively identifies nearly two thirds of children with CHARGE syndrome, diagnosis is still largely clinical:

  • C - Coloboma of the eye, central nervous system anomalies
  • H - Heart defects
  • A - Atresia of the choanae
  • R - Retardation of growth and/or development
  • G - Genital and/or urinary defects (Hypogonadism)
  • E - Ear anomalies and/or deafness

Genetic testing

Genetic testing for CHARGE syndrome involves specific genetic testing for the CHD7 gene. As mentioned above, in a US study of 110 people, only 60% of those diagnosed clinically with CHARGE syndrome had a positive genetic test.

The availability of this genetic test is not widespread. The test is available at Emory University and the University of Chicago. The test is expensive, currently $2400 at the University of Chicago (plus additional costs charged by the facility or doctor's office that is actually drawing the blood). Insurance companies sometimes do not pay for such genetic tests, though this is changing rapidly as genetic testing is becoming standard across all aspects of medicine. For some physicians, the current standard of care is to diagnose cases of CHARGE syndrome based on clinical features alone.

Completion of diagnosis

Once the diagnosis of CHARGE syndrome is made based on some of the clinical signs, it is important to investigate the other body systems that may be involved.

For example, if the diagnosis of CHARGE syndrome is made based on the abnormal appearance of the ears and developmental delay, it is important to check the child's hearing, vision, heart, nose, and urological system (check for hypospadias, undescended testicles, or other urinary abnormalities). Thus, every child newly diagnosed with CHARGE syndrome should have a complete evaluation by an ENT specialist, audiologist (to check for hearing, unless this is also checked by the ENT specialist), ophthalmologist, pediatric cardiologist, developmental therapist, and pediatric urologist.


 

Treatment

Children with CHARGE syndrome can have many life-threatening issues; with advances in medical care these children can survive and become healthy and happy individuals. Appropriate therapies and educational intervention for individuals with CHARGE syndrome must take into consideration hearing impairment, vision problems, and any other medical conditions that are present. Early intervention, such as occupational and physical therapy, is very important as the intelligence of children with multiple health issues such as combined deaf-blindness is often underestimated. Because of the developmental delay, early intervention can play an important role in promoting mobility, improving static postures, transitioning towards ambulation, and teaching self care skills. Both physicians and parents need to be made aware that these children can thrive with the support of a team of medical professionals. Management should be by a multidisciplinary team and coordinated by a single person, if possible.