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CHARGE syndrome

By: C. J. Fields

What is CHARGE syndrome?

CHARGE syndrome is an identified (genetic) pattern of birth defects which occurs in about one in every 9 -10,000 births worldwide. CHARGE is a variegated syndrome, that is characterized by extensive medical and physical difficulties that differ from child to child. The majority of CHARGE syndrome births are not indicated by family history or any other similar conditions in the family. Babies with CHARGE syndrome are often born with life-threatening birth defects, including heart abnormalities and respiratory issues. “CHARGE” originally came from the first letter of some of the most common features observed in theses children:

  • C=coloboma of the eye
  • H=heart defects
  • A=atresia of the choanae
  • R=retardation of growth and development
  • G=genital and urine abnormalities
  • E=ear abnormalities and/or hearing loss

Cause and Diagnostic Criteria

A mutation of the CHD7 gene is the suspected cause of CHARGE syndrome. Gene testing is very expensive and isn't always reliable - only about 2/3 of people with CHARGE test positively for the CHD7 gene mutation. Therefore, the diagnosis of CHARGE syndrome is clinical, and is based on a variety of medical features seen in the child. Evaluations for CHARGE syndrome should be made by a geneticist that specializes in CHARGE. A diagnosis can be made using a combination of Major and Minor features. “Major features are characteristics that are quite common in CHARGE syndrome but relatively rare in other conditions, and are, for the most part, diagnosable in the newborn period.”

“Minor features are characteristics which are also common in CHARGE, but not quite as helpful in distinguishing CHARGE from other syndromes.” (The CHARGE Syndrome Foundation, 2013) 

Major Features of CHARGE Syndrome
Feature Includes Frequency
Coloboma of the eye Coloboma (sort of like a cleft) of the iris, retina, choroid, macula or disc (not the eyelid); microphthalmos (small eye) or anophthalmos (missing eye): CAUSES VISION LOSS 80% - 90%
Choanal atresia or stenosis The choanae are the passages that go from the back of the nose to the throat. They can be narrow (stenosis) or blocked (atresia). It can be unilateral (one-sided) or bilateral (both sides), bony or membranous. 50% - 60%
Cranial nerve abnormality I - Missing or decreased sense of smell, IX/X - Swallowing difficulties, aspiration, VII - Facial palsy (one side or both) 90% - 100%, 70% - 90%, 40%
CHARGE outer ear Short, wide ear with little or no lobe, "snipped off" helix (outer fold), prominent antihelix (inner fold) which is discontinuous with tragus, triangular concha, decreased cartilage (floppy), often stick out, usually asymmetric. > 50%
CHARGE middle ear Malformed bones of the middle ear (ossicles): CAUSES CONDUCTIVE HEARING LOSS Common
CHARGE inner ear Malformed cochlea (Mondini defect); small or absent semicircular canals: CAUSE HEARING LOSS AND BALANCE PROBLEMS 90%

Minor Features of CHARGE Syndrome
Feature Includes Frequency
Heart defects Can be any type, but many are complex, such as tetralogy of Fallot 75%
Cleft lip +/- cleft palate Cleft lip with or without cleft palate, cleft palate, submucous cleft palate 20%
TE fistula Esophageal atresia, Trancheo-esophageal fistula (TEF), H-shaped TEF 15% - 20%
Kidney abnormalities Small kidney, missing kidney, misplaced kidney, reflux 40%
Genital abnormalities Males: small penis, undescended testes. Females: small labia, small or missing uterus. Both: lack of puberty without hormone intervention 50%, 25%, 90%
Growth deficiency Growth hormone deficiency, Other short stature 15%, 70%
Typical CHARGE Face Square face with broad prominent forehead, arched eyebrows, large eyes, occasional ptosis (droopy lids), prominent nasal bridge with square root, thick nostrils, prominent nasal columella (between the nostrils), flat midface, small mouth, occasional small chin, larger chin with age. Facial asymmetry even without facial palsy. Varies
Palm crease Hockey-stick palmar crease 50%
CHARGE Behavior Perseverative behavior in younger individuals, obsessive compulsive behavior (OCD) in older individuals > 50%

* None of the above features are necessary for a CHARGE diagnosis. These features may vary from severe to absent in children with CHARGE.

Medical Management and Surgeries

Surgical treatment is necessary in children with CHARGE syndrome to correct congenital anomalies. Example surgical interventions include: Tracheostomy - which is done to stabilize the air passage; Myringotomy and tymphonostomy tubes which is done to treat otitis media; Gastrostomay and fundoplication in cases of feeding difficulty, and cochlear implantation. In addition to available surgeries, appropriate medical management of CHARGE syndrome is necessary.

Resources:

  • Chargesyndrome.net (2013). CHARGE syndrome treatment.
  • The Charge Syndrome Foundation (2013). 推荐杏吧原创 CHARGE.