Ocular findings in CHARGE syndrome. Six case reports and a review

CHARGE syndrome and congenital heart diseases: systematic review of literature

CHARGE syndrome (CS) is a rare genetic disease that affects many areas of the body. The aim of the present systematic review was to evaluate the prevalence and types of congenital heart diseases (CHDs) in CS and their impact on clinical outcome. A systematic review from 1981 to September 2022 was conducted. Clinical studies that reported the association between CS and CHDs were identified, including a case report of a rare congenital anomaly of the aortic arch (AA) with persistent fifth aortic arch (PFAA). Demographic, clinical and outcome data were extracted and analyzed. Sixty-eight studies (44 case reports and 24 case series; n=943 CS patients) were included. The prevalence of CHDs was 76.6%, patent ductus arteriosus (PDA) 26%, ventricular (VSD) 21%, atrial septal defects (ASD) 18%, tetralogy of Fallot 11%, aortic abnormalities 24%. PFAA has not been previously reported in CS. Cardiac surgery was performed in more than half of CS patients (150/242, 62%). In-hospital mortality rate was about 9.5% (n=86/900) in case series studies and 12% (n=5/43) in case reports, including cardiovascular (CV) and non-CV causes. CHDs and feeding disorders associated with CS may have a substantial impact on prognosis. CHDs were usually associated with CS and represent important causes of morbidity and mortality. PFAA, although rare, may also be present. The prognosis is highly dependent on the presence of cardiac and non-cardiac developmental abnormalities. Further studies are needed to better identify the main causes of the long-term outcome of CS patients.

CHARGE syndrome without colobomas: Ophthalmic findings

To report ophthalmic findings of patients without colobomas, and with a clinical and molecular diagnosis of CHARGE Syndrome. Retrospective study of ophthalmic findings in 67 CHARGE patients-clinically confirmed diagnosis with positive CHD7 mutation-seen in the Ophthalmology department of Cincinnati Children's Hospital Medical Center between January 1, 2008 through September 25, 2018. Criteria for inclusion in this study was absence of any form of a coloboma in either eye. In our cohort, all patients had a positive CHD7 mutation, in addition to a clinical diagnosis. 19.4% (13/67) of CHARGE patients did not have a coloboma in either eye. 69.2% (9/13) had strabismus, 76.9% (10/13) had a refractive error that warranted refractive correction, 23.1% (3/13) had amblyopia, 38.5% (5/13) had nasolacrimal duct obstruction, 30.8% (4/13) had dry eye syndrome and exposure keratopathy, 15.4% (2/13) had ptosis, 15.4% (2/13) had blepharitis, 15.4% (2/13) had Cortical Visual Impairment, 7.7% (1/13) of patients had optic nerve drusen, 7.7% (1/13) had Marcus Gunn Jaw Winking, and 7.7% (1/13) with an eyelid nevus. There are numerous ophthalmic findings in individuals with CHARGE Syndrome without colobomas. No study to date has evaluated the ophthalmic findings in CHD7 positive CHARGE patients without colobomas. These findings need to be assessed and treated to ensure optimal vision in the CHARGE patient population. Absence of coloboma does not rule out a diagnosis of CHARGE syndrome, and if there is a clinical suspicion, clinical confirmation then genetic testing would be warranted.

Symmetrical Chorioretinal Colobomata with Craniovertebral Junction Anomalies in CHARGE Syndrome - A Case Report with Review of Literature

CHARGE syndrome is a common cause of congenital anomalies. Its rate of incidence is about 1:10,000. It is phenotypically heterogeneous, usually a sporadic or autosomal dominant disorder resulting from a mutation in the CHD7 (chromodomain helicase DNA-binding protein) gene. Since the time it was first described by Hall,[1] the knowledge of the clinical characteristics of CHARGE syndrome has increased over the years. Recently, basiocciput hypoplasia and basilar invagination in patients with CHARGE syndrome have been reported. We report here a case of CHARGE syndrome where there is involvement of symmetrical chorioretinal colobomata with craniovertebral junction anomalies. The patient had symmetrical chorioretinal colobomata, external and inner ear anomalies, sensorineural deafness, characteristic facial appearance, retarded growth and development, history of patent ductus arteriosus, and craniovertebral junction anomalies. Craniovertebral junction anomalies may be an under-diagnosed phenotypic expression of CHARGE syndrome. The diagnostic criteria of CHARGE syndrome may require further revision to include the addition of craniovertebral junction anomalies.

The optic nerve and visual pathways

We review the clinical examination of the optic disc and assessment of the integrity of the visual pathways: assessment of vision in the infant and child, assessment of disc size and configuration, detection of abnormalities such as cupping or disc swelling and their significance, visual field examination in the child, and the various field defects which result from pathology affecting the visual pathway anywhere along its course. Congenital anomalies of the optic disc, their systemic associations and significance are discussed. We also review the presentation of the visually impaired child, the significance of nystagmus in this context, the differential diagnosis and investigation.

Ocular features of CHARGE syndrome

PURPOSE

To detail the presence and severity of ocular and cranial nerve abnormalities found in individuals with CHARGE syndrome in a distinct geographic area.

METHODS

Nine individuals with CHARGE syndrome from Maritime Canada identified from a Canadian database were prospectively examined. Structural and sensorial defects associated with functional visual deficits were defined with ophthalmic and neurological evaluation.

RESULTS

Consistent with current diagnostic criteria and the literature, colobomas were the major ophthalmic manifestation. These were typically bilateral chorioretinal colobomas involving the optic nerve. All subjects had bilateral severe sensorineural deafness (cranial nerve VIII), and 8 of 9 (89%) had facial nerve (cranial nerve VII) involvement (7 of 9 had unilateral involvement; 1 of 9 had bilateral involvement). Unique to this group of participants were the findings of anisometropia in 8 of the 9 (89%) patients, severe myopic astigmatism in 13 of the 18 eyes (72%), and limited elevation in adduction in 3 of 9 (33%) participants. Associated findings were strabismus, cataracts, microcornea, keratopathy, staphyloma, reduced stereopsis, superior visual field defects, and reduced visual acuity.

CONCLUSIONS

The presence of coloboma plus another CHARGE feature warrants further investigation, including genetic screening for the CHD7 gene. Early recognition and management of sensory problems (visual, auditory, and vestibular) are crucial to ensure best psychomotor and cognitive development.

Familial CHARGE syndrome and the CHD7 gene: a recurrent missense mutation, intrafamilial recurrence and variability

CHARGE syndrome is an autosomal dominant condition that is caused by mutations in the CHD7 gene. Few familial cases of this syndrome have been reported and these were characterized by a wide clinical variability. We here report on five CHD7 mutation positive families and comment on their clinical features. We observed somatic and germline mosaicism as well as parent-to-child transmission of non-mosaic CHD7 mutations as causes of familial CHARGE syndrome. In one family with two affected sibs a somatic mutation was identified in lymphocytes of a clinically unaffected parent (2520G > A in exon 8). This is the second report of somatic CHD7 mosaicism in an unaffected parent. In two further families with affected siblings, we could not detect the mutation in parental lymphocytes suggesting germline mosaicism. The previously reported clinical variability was strikingly present in all five families. We find that alterations in CHD7 can result in a very mild phenotype, characterized by only a few minor symptoms of the CHARGE syndrome clinical spectrum. Such a mild phenotype was present in two families that shared the same 6322G > A missense mutation. These two families showed parent-to-child transmission. Phenotypically milder forms of CHARGE syndrome have a higher risk of transmission to multiple family members.

CHARGE syndrome: an update

CHARGE syndrome is a rare, usually sporadic autosomal dominant disorder due in 2/3 of cases to mutations within the CHD7 gene. The clinical definition has evolved with time. The 3C triad (Coloboma-Choanal atresia-abnormal semicircular Canals), arhinencephaly and rhombencephalic dysfunctions are now considered the most important and constant clues to the diagnosis. We will discuss here recent aspects of the phenotypic delineation of CHARGE syndrome and highlight the role of CHD7 in its pathogeny. We review available data on its molecular pathology as well as cytogenetic and molecular evidences for genetic heterogeneity within CHARGE syndrome.

Multiple mutations in mouse Chd7 provide models for CHARGE syndrome

Mouse ENU mutagenesis programmes have yielded a series of independent mutations on proximal chromosome 4 leading to dominant head-bobbing and circling behaviour due to truncations of the lateral semicircular canal of the inner ear. Here, we report the identification of mutations in the Chd7 gene in nine of these mutant alleles including six nonsense and three splice site mutations. The human CHD7 gene is known to be involved in CHARGE syndrome, which also shows inner ear malformations and a variety of other features with varying penetrance and appears to be due to frequent de novo mutation. We found widespread expression of Chd7 in early development of the mouse in organs affected in CHARGE syndrome including eye, olfactory epithelium, inner ear and vascular system. Closer inspection of heterozygous mutant mice revealed a range of defects with reduced penetrance, such as cleft palate, choanal atresia, septal defects of the heart, haemorrhages, prenatal death, vulva and clitoral defects and keratoconjunctivitis sicca. Many of these defects mimic the features of CHARGE syndrome. There were no obvious features of the gene that might make it more mutable than other genes. We conclude that the large number of mouse mutants and human de novo mutations may be due to the combination of the Chd7 gene being a large target and the fact that many heterozygous carriers of the mutations are viable individuals with a readily detectable phenotype.

Ribosomal protein L24 defect in belly spot and tail (Bst), a mouse Minute

Ribosomal protein mutations, termed Minutes, have been instrumental in studying the coordination of cell and tissue growth in Drosophila. Although abundant in flies, equivalent defects in mammals are relatively unknown. Belly spot and tail (Bst) is a semidominant mouse mutation that disrupts pigmentation, somitogenesis and retinal cell fate determination. Here, we identify Bst as a deletion within the Rpl24 riboprotein gene. Bst significantly impairs Rpl24 splicing and ribosome biogenesis. Bst/+ cells have decreased rates of protein synthesis and proliferation, and are outcompeted by wild-type cells in C57BLKS<-->ROSA26 chimeras. Bacterial artificial chromosome (BAC) and cDNA transgenes correct the mutant phenotypes. Our findings establish Bst as a mouse Minute and provide the first detailed characterization of a mammalian ribosomal protein mutation.

Quantitative analysis of limb anomalies in CHARGE syndrome: correlation with diagnosis and characteristic CHARGE anomalies

CHARGE syndrome was initially not thought to involve the limb. Several subsequent reports have shown that limb anomalies are not uncommon. To date, there have been no quantitative studies of limb anomalies in CHARGE syndrome. This study was designed to answer several questions: Do CHARGE patients with limb anomalies represent a subgroup within CHARGE syndrome? Are there correlations between certain CHARGE syndrome anomalies and limb anomalies?Are there differences between the two genders and associated limb anomalies? Are certain types of limb anomalies seen with increased frequency in CHARGE syndrome? All described patients were categorized utilizing the AI/GEN Model 2 Criteria proposed by Mitchell [1985a: J Med Syst 9:425-435]. Patients with chromosomal anomalies or familial CHARGE were excluded, as were patients with inadequate clinical descriptions, and patients in large series where individual characteristics could not be ascertained. Multivariate analysis was performed. One hundred seventy two patients with definite or probable CHARGE syndrome were analyzed. Sixty-four (37.2%) of these patients have at least one limb anomaly. Significant positive associations were seen between limb anomalies and ocular coloboma, urinary tract malformations, and genital anomalies. These associations were not significant when the definite or probable patients were analyzed separately, with the exception of genital anomalies in definite CHARGE. Gender differences were also identified. Females with tracheoesophageal fistula/esophageal atresia, or genital anomalies were more likely to have limb anomalies, while some female subgroups had positive associations between urinary tract malformations, or choanal atresia and limb anomalies. Negative associations were also seen with sensorineural hearing loss and facial paralysis. In contrast, males showed a positive association between coloboma and limb anomalies, while subgroup analysis identified positive associations with DiGeorge sequence or genital anomalies and limb anomalies. Limb anomalies are present in just over one-third of CHARGE syndrome patients. Limb anomalies are seen more frequently in association with certain CHARGE anomalies, and these associations show gender differences. There is not a common limb anomaly seen in CHARGE syndrome.

Ocular pathology in congenital heart disease

PURPOSE

To describe the ocular findings in subjects with congenital heart disease (CHD).

METHODS

In a prospective study, the same observer examined 240 consecutive patients with CHD admitted to the medical centre. Two independent geneticists performed identification of syndromes.

RESULTS

The commonest anatomic cardiac anomalies were ventricular or atrial septal defects (62), tetralogy of Fallot (39), pulmonary stenosis (25), and transposition of the great arteries (24). The heart lesions were divided physiologically into volume overload (90), cyanotic (87), and obstructive (63). In all, 105 syndromic subjects included the velocardiofacial syndrome (18), Down's syndrome (17), CHARGE association (6), DiGeorge syndrome (5), Williams syndrome (3), Edwards syndrome (3), Noonan syndrome (3), VACTERL association (2), and Patau syndrome (trisomy 13) (2). The paediatric team recognized 51 patients as syndromic. Two independent geneticists recognized additional 54 patients as syndromic. Positive eye findings were present in 55% (132) and included retinal vascular tortuosity (46), optic disc hypoplasia (30), trichomegaly (15), congenital ptosis (12), strabismus (11), retinal haemorrhages (8), prominent eyes (7), and congenital cataract (6). There was a strong correlation between the retinal vascular tortuosity and both a low haematocrit (P=0.000) and a low arterial oxygen saturation (P=0.002).

CONCLUSIONS

Patients with CHD are at a high risk for ocular pathology and need screening for various ocular abnormalities.

CHARGE syndrome: a window of opportunity for audiologic intervention

OBJECTIVE

To detail the clinical features of 22 new patients with a syndrome characterized by ocular coloboma, heart defects, atretic choanae, retarded growth or development, genital hypoplasia, and ear anomalies or hearing loss (CHARGE) seen in a tertiary academic medical center; compare auditory brainstem response (ABR) thresholds and behavioral hearing test results; identify a "window of opportunity" for audiologic intervention; review the literature regarding hearing results in CHARGE syndrome; and review the relationship between facial palsy and sensorineural hearing loss.

METHODS

Clinical data were gathered to examine 1) the variety of hearing results, 2) the average age at the time of hearing loss identification in 22 children with CHARGE using electrophysiologic and behavioral test methods, 3) the usefulness of the ABR as an early indicator of hearing sensitivity for a select group composed of children from the present study and from an earlier report from the same institution, and 4) the value of congenital facial paralysis as a predictor of sensorineural hearing loss in CHARGE children seen in the authors' institution since 1983.

RESULTS

All children had 4 or more acronymic features, including colobomatous defects or choanal atresia. Ear anomalies/hearing loss occurred at least as frequently as other primary features. A total of 81% of patients had hearing loss; in this subset, 1 child had a mild degree of loss, and the remaining children had moderate or greater losses. The average age at which ABR confirmed hearing status was 3.8 months, whereas for behavioral testing, that age was 24.7 months, a statistically significant difference. In a select group of 16 children, no statistical differences existed when comparing threshold results of early electrophysiologic testing with behavioral test findings obtained at a later date. Contingency analysis suggests that congenital facial paralysis and sensorineural hearing loss are related.

CONCLUSIONS

Hearing loss is prevalent in children with CHARGE syndrome. Within a wide range of results exists a propensity for moderate or greater hearing loss in children with sensorineural or mixed impairments. Congenital facial palsy seems to be a valid statistical predictor of sensorineural hearing loss and can be a useful device in audiologic decision making. A "window of opportunity" for audiologic intervention exists in the first few months of life. Primary care providers are encouraged to recognize the need for immediate, early audiologic referral of their patients suspected to have CHARGE. Evaluation of hearing sensitivity during infancy and, when appropriate, provision of amplification are important components in the process of auditory habilitation. These efforts are in keeping with various professional guidelines that call for early detection of hearing loss and subsequent prompt intervention to minimize effects on infant development.

Renal-coloboma syndrome: report of a novel PAX2 gene mutation

PURPOSE

To report a novel sporadic PAX2 gene mutation in a child with atypical bilateral optic nerve coloboma and congenital renal hypoplasia.

DESIGN

Observational case report and experimental study.

METHODS

Mutational analysis of the PAX2 gene in a family.

RESULTS

A 9-year-old patient with a history of renal transplantation for congenital renal hypoplasia was found to have bilateral optic nerve coloboma during ophthalmic examination for cytomegalovirus retinitis. A previously unreported mutation in exon 2, delT 602 leading to a prematurely truncated protein was identified in the child but in neither of her parents, demonstrating a de novo mutation or germline mosaicism.

CONCLUSIONS

The causal relationship between PAX2 gene mutations and renal-coloboma syndrome is further supported by this novel mutation. Awareness of the systemic associations with optic nerve abnormalities and the ocular findings in syndromic renal diseases will facilitate the management of these highly variable disorders.

CHARGE syndrome: report of 47 cases and review

The acronym CHARGE refers to a syndrome of unknown cause. Here we report on 47 CHARGE patients evaluated for the frequency of major anomalies, namely coloboma (79%), heart malformation (85%), choanal atresia (57%), growth and/or mental retardation (100%), genital anomalies (34%), ear anomalies (91%), and/or deafness (62%). In addition, we comment on anomalies observed very frequently in neonates and infants with the CHARGE syndrome, including, minor facial anomalies, neonatal brain stem dysfunction with cranial nerve palsy, and, mostly, internal ear anomalies such as semicircular canal hypoplasia that were found in each patient that could be tested. We propose several criteria for poor survival including male gender, central nervous system and/or oesophageal malformations, and bilateral choanal atresia. No predictive factor regarding developmental prognosis could be identified in our series. A significantly higher mean paternal age at conception together with concordance in monozygotic twins and the existence of rare familial cases support the role of genetic factors such as de novo mutation of a dominant gene or subtle sub-microscopic chromosome rearrangement. Finally, the combination of malformations in CHARGE syndrome strongly supports the view that this multiple congenital anomalies/mental retardation syndrome is a polytopic developmental field defect involving the neural tube and the neural crests cells.

CHARGE association: histopathological report of two cases and a review

BACKGROUND

The CHARGE association (C = coloboma, H = heart disease, A = atresia or stenosis of the choanae, R = retarded growth and development or CNS anomalies, G = genital hypoplasia, and E = ear anomalies or deafness) is a rare, recently well-recognized clinical study. The ophthalmic abnormalities have been described in numerous reports, but the ocular histopathologic findings have not been presented in detail.

METHODS

We conducted gross and microscopic studies of eyes of two patients with the CHARGE association obtained postmortem.

RESULTS

The eyes in one case had a small, symmetrical, inferior nasal coloboma of the choroid. In the other case, extensive inferior nasal colobomas of the iris, ciliary body, and choroid with retinal dysplasia, ectopic retinal/glial tissue in the sclera and hypoplasia of the optic nerve head were present.

CONCLUSION

We document the histopathological features of eyes of two subjects with the CHARGE association. The abnormalities of these eyes were typical ocular colobomas presumably resulting from the failure of complete closure of the optic fissure.

CHARGE association with congenital glaucoma due to maldevelopment of the anterior chamber angle

PURPOSE

We examined the clinicopathologic features of a male infant with the CHARGE association and bilateral congenital glaucoma.

METHODS

Trabeculectomy specimens were obtained from the anterior chamber angle and examined by light and electron microscopy.

RESULTS

Histopathologic examination of the trabeculectomy specimens showed immature development of the trabecular meshwork that was covered by the ciliary muscles. There were few intertrabecular spaces because the meshwork was almost completely filled with cells and extracellular substances. Deposition of a granular and/or homogeneous substance was observed in the subendothelial area of Schlemm's canal.

CONCLUSIONS

Our patient exhibited features typical of the CHARGE association, but also had congenital glaucoma. We hypothesize that these clinical findings are all mediated by a neurocristopathic mechanism. Our findings suggest that the CHARGE association may predispose to anterior chamber angle maldevelopment, which can lead to congenital glaucoma.

Vestibular areflexia as a cause of delayed motor skill development in children with the CHARGE association

Six cases of the CHARGE association are described that were encountered consecutively at an institute for the deaf. Five of them showed external ear anomalies and according to expectations all of them showed some degree of hearing impairment: two had moderate mixed hearing loss; three had severe to profound sensorineural hearing loss; and one was completely deaf. In addition, they all had vestibular areflexia and the five cases examined with computer tomography of the petrosal bones showed aplasia of the semicircular canals. One case with poor visual acuity also showed subnormal optokinetic responses and horizontal pendular nystagmus during visual fixation. All these children were initially diagnosed as having severe psychomotor retardation, because of their failure to acquire speech and their delayed motor skill development. Given the fact that (mild) mental retardation was found in only one case, the delayed development could at least in part have been caused by vestibular areflexia. The vestibular findings support previously reported temporal bone findings that indicate dysplasia or aplasia of the superior part of the labyrinth. Early detection of the full extent of (multiple) sensory deficits is necessary in children with the CHARGE association who have similar abnormalities, because aggressive intervention and special educational support are likely to be of great benefit to sensorimotor development.

Non-cardiac malformations in individuals with outflow tract defects of the heart: the Baltimore-Washington Infant Study (1981-1989)

In the Baltimore-Washington Infant Study, a regional case-control study of 4,390 liveborn infants with cardiovascular malformations (CVM), 642 patients (14.2%) had outflow tract abnormalities, with extracardiac defects in 157 (approximately 25%) of them. Associated defects were found in 1/3 of patients with normal great arteries, but only in 1/10 of patients with transposition of great arteries (TGA). The extracardiac defects were especially rare in the groups "TGA with intact ventricular septum" and "TGA with ventricular septal defect". Patients with multiple associated defects outnumbered patients with isolated associated defects in the ratio 2.5:1. The associated defects were heterogeneous: 46 patients had chromosome abnormalities, 16 had different Mendelian syndromes, and 36 had associations (DiGeorge sequence and VACTERL association were the most frequent). A new syndrome of multiple congenital abnormalities including tetralogy of Fallot, and rare cases of chromosomal and Mendelian syndromes (distal trisomy 1q, tetrasomy 8p, Holzgreve syndrome) are described briefly. Sufficient variability of a spectrum of conotruncal defects in the patients with the same chromosomal or Mendelian syndromes suggests that at least in some cases different conotruncal defects are stages of the same morphologic spectrum. The analysis of conotruncal defects in sibs of patients with Mendelian syndromes may provide new data about the links between different definitive forms of CVM.

Congenital optic disk anomalies

Over the past decade, a wealth of information has accumulated pertaining to the diagnosis and management of patients with congenital optic disk anomalies. As new examples of each entity have been detailed, the diagnostic criteria for each anomaly have become more clearly defined. The advent of sophisticated noninvasive neuroimaging techniques has further refined our ability to accurately detect and categorize the associated CNS anomalies that complicate many of these conditions. In light of recent findings, this review will critically examine many of the well-entrenched concepts pertaining to the diagnosis, evaluation, and treatment of patients with congenital optic disk anomalies. In so doing, it will attempt to dispel some longstanding misconceptions that pervade the literature and obscure our understanding of the pathogenesis, neuroradiological associations, and systemic implications of each anomaly.

Cranial nerve abnormalities in CHARGE association

Many children with the CHARGE association have facial paralysis and feeding and swallowing difficulties. Indeed, facial paralysis and pharyngeal incoordination may be important diagnostic indicators of CHARGE association [Davenport et al., 1986a; Mitchell et al., 1985]. We describe an individual with dysfunction of multiple cranial nerves (Möbius sequence) and CHARGE association, a previously unrecognized combination. Our review of 150 patients from the literature and 13 patients from this center with CHARGE association documented that dysfunction of cranial nerves is frequent in CHARGE association, and that often cranial nerve abnormalities are multiple. Such multiple cranial nerve abnormalities may be the primary underlying cause for the facial paralysis, feeding difficulties and sensorineural hearing loss seen in many individuals with CHARGE association.

CHARGE and esophageal atresia

CHARGE association was diagnosed in 61 infants, 20 of whom died, mainly during the first 2 years of life. Esophageal atresia and/or tracheoesophageal fistula were present in 10 neonates. Axial skeletal anomalies occurred in 7 of the 10, but none had preaxial limb defects typical of the VATER association. All had major cardiac anomalies, predominantly tetralogy of Fallot. The majority of patients had primary repair of the esophagus. The postoperative course was stormy in all patients, with a high incidence of complications and 70% died. The recognition of features of the CHARGE association is important because it has major prognostic and therapeutic implications.

Central nervous system malformations in the CHARGE association

Of 144 patients with the CHARGE association (literature 136, new patients 8), 47 (33%) had either a postmortem examination (30) or computerized axial tomography scan (17) of the head. Twenty-six of 47 (55%) had definite central nervous system (CNS) malformations; arhinencephaly, with or without other defects (11), holoprosencephaly (2), holoprosencephaly with arhinencephaly (1), other forebrain defects (3), hindbrain defects (3), or other defects (6). The presence of CNS malformation was most strongly associated with choanal atresia. This review demonstrates a predominance of forebrain anomalies, particularly arhinencephaly and holoprosencephaly, which may provide a clue to the mechanism of abnormal morphogenesis involved in CHARGE association.

CHARGE and Joubert syndromes: are they a single disorder?

A patient with the CHARGE association (Coloboma of the eye, Heart defect, Atresia of the choana, Retarded growth and development, Genital hypoplasia, and Ear anomalies or deafness) had intermittent hyperpnea and cerebellar hypoplasia; therefore, he had both the CHARGE association and Joubert syndrome. The 2 syndromes have not been previously linked. We discuss their similarities and review the literature.

The eye in the CHARGE association

CHARGE association includes patients with at least four features prefixed by the letters of the mnemonic: Coloboma, Heart defects, Atresia of the choanae, Retarded growth and development, Genital hypoplasia, Ear anomalies and/or hearing loss. Many also have facial palsy. We report a series identified by collaboration within one centre of all specialties concerned in the management of the CHARGE association. Ocular abnormalities were found in 44 out of 50 patients with the CHARGE association. Of these, 41 had 'typical' colobomata. The majority had retinochoroidal colobomata with optic nerve involvement, but only 13 patients had an iris defect. Two patients had atypical iris colobomata with normal fundi. Additional features were microphthalmos in 21 patients, optic nerve hypoplasia in four, nystagmus in 12, and a vertical disorder of eye movement in four of the 22 cases with facial palsy. We report an incidence of coloboma in the CHARGE association of 86% (43/50) compared with a previous cumulative reported incidence of 66% (112/170). We believe that there may have been previous underdiagnosis of colobomata in children with multiple congenital abnormalities.