This Article  • Extract  • PDF  • Reply to article  • Send to a friend  • Save in My Folder  • Save to citation manager  • Permissions  Citing Articles  • Contact me when this article is cited  Related Content  • Similar articles in this journal  Topic Collections  • Retinal/ Chorioretinal Disorders  • Alert me on articles by topic

Arch Ophthalmol. 2004;122:1232-1233.

Coats disease is an uncommon exudative retinopathy of unknown origin that may cause blindness. We report the unusual occurrence of Coats disease in a 5-year-old boy with multiple congenital abnormalities due to VATER association. The possibility of a genetic basis for some cases of Coats disease is discussed.

The VATER association comprises congenital defects including vertebral defects, imperforate anus, tracheoesophageal fistula, and radial and renal dysplasia.¹ The underlying cause of VATER association may be a severe embryonic insult during the simultaneous development of the organ systems.¹ Patients with VATER association often require multiple surgical procedures and extensive rehabilitation. We report a unique case of exudative retinopathy (Coats disease) in a case of VATER association.

Report of a Case
A child with a normal prenatal ultrasound at 20 weeks gestation and a negative TORCH (toxoplasmosis, other infections, rubella, cytomegalovirus infection, and herpes simplex) panel was born after an otherwise uncomplicated pregnancy by normal spontaneous vaginal delivery at 33 weeks gestational age. The results of a physical examination at birth revealed an imperforate anus and polydactyly with an extra digit lateral to the right thumb. The results of a radiological examination showed communicating hydrocephalus with grade II bilateral renal reflux and hemivertebra with severe scoliosis (Figure 1A. Corrective surgical procedures included digit amputation, colostomy, and anoplasty. There was no family history of eye or genetic defects, and karyotyping was normal in the child and his parents.

View larger version (50K): [in this window] [in a new window] A, Scout film of a computed tomography scan showing absent hemivertebrae (arrows) and severe scoliosis typical of VATER association. B, Indirect funduscopy photograph showing severe exudative retinopathy with retinal detachment.

At 5 years of age, the patient was referred for left eye leukocoria. Visual acuity was 20/20 OD and 1/60 OS. There was total exudative retinal detachment with associated tortuous vessels with multiple aneurysmal dilatations compatible with Coats disease, stage 3B (Figure 1B.² The lower 2 quadrants of the retina were preferentially affected. There was no evidence of associated anterior chamber or vitreal inflammation. The findings of the retinal examination of the fellow eye, including the periphery area, were normal. Further examination of old photographs showed the patient had had leukocoria since the age of 6 months. The results of B-scan ultrasonography revealed retinal detachment with no calcification or mass. This was confirmed by a computed tomography scan of the orbits. Intraocular pressure was normal with no evidence of neovascularization of the iris. Cryotherapy was offered to the patient to preserve vision and prevent further complications, including neovascular glaucoma, a painful blind eye, and a possible need for enucleation. The parents finally opted for conservative treatment.

Comment
A number of patients with VATER association have been described as having eye defects.¹ The most common associations are coloboma and microphthalmos.³ However, the retina and posterior segment are seldom involved, and Coats disease was hitherto unreported. The term Coats disease refers to idiopathic retinal telangiectasia with intraretinal or subretinal exudation and without appreciable signs of retinal or vitreal traction. The diagnosis of Coats disease is one of exclusion after careful workup and examination, especially with regard to retinoblastoma, retinopathy of prematurity, retinal capillary angiomatosis, and toxocara, all of which were not implicated in our case. Reported associations include renal-retinal abnormalities and retinal disorders.⁴ Familial forms exist, but no specific gene defect is known. In the largest reported series, the median age of diagnosis was 5 years with a male predominance (76%), the majority with unilateral disease (95%).² Aggressive management for early cases, including laser photocoagulation, cryotherapy, and drainage of subretinal exudates using pars plana vitrectomy techniques, may prevent neovascular glaucoma and a painful blind eye.

Because the definitive genetic defects for both VATER association and Coats disease in humans are unknown, we can only speculate about the possible common genetic link. Recently, an adriamycin-induced rat model of the VATER association, with defects in the hedgehog gene pathway, has been developed.⁵ The secreted glycoprotein, sonic hedgehog (SHH), acts as an endodermal signal that controls gut and lung patterning. Interestingly, the SHH protein is also secreted by retinal ganglion cells to help optic disc astrocyte precursor cells to guide retinal axon growth, and to convert optic stalk neuroepithelial cells into pigmented cells. Both VATER and retinal defects can be produced by targeted SHH mutations. Ultrastructural retinal cell abnormalities are not infrequently found in pathologically examined eyes of patients with Coats disease.⁶ Nevertheless, it remains to be elucidated whether any aberrations in these pathways may explain the unusual clustering of specific defects in our case.

The authors have no relevant financial interest in this article.

AUTHOR INFORMATION

Charmaine Hon, FRCS; Tak-chuen Ko, FRCS

Correspondence: Dr Hon, Department of Ophthalmology, Prince of Wales Hospital, Shatin, Hong Kong (honc{at}ha.org.hk).

REFERENCES
1. Say B, Greenberg D, Harris R, DeLong SL, Coldwell JG. The radial dysplasia/imperforate anus/vertebral anomalies syndrome (the VATER association): developmental aspects and eye findings. Acta Paediatr Scand. 1977;66:233-235. ISI | PUBMED 2. Shields JA, Shields CL, Honavar SG, Demirci H, Cater J. Classification and management of Coats disease: the 2000 Proctor Lecture. Am J Ophthalmol. 2001;131:572-583. FULL TEXT | ISI | PUBMED 3. Warburg M. Update of sporadic microphthalmos and coloboma: non-inherited anomalies. Ophthalmic Paediatr Genet. 1992;13:111-122. ISI | PUBMED 4. den Hollander AI, Heckenlively JR, van den Born LI, et al. Leber congenital amaurosis and retinitis pigmentosa with Coats-like exudative vasculopathy are associated with mutations in the crumbs homologue 1 (CRB1) gene. Am J Hum Genet. 2001;69:198-203. FULL TEXT | ISI | PUBMED 5. Arsic D, Qi BQ, Beasley SW. Hedgehog in the human: a possible explanation for the VATER association. J Paediatr Child Health. 2002;38:117-121. PUBMED 6. McGettrick PM, Loeffler KU. Bilateral Coats' disease in an infant (a clinical, angiographic, light and electron microscopic study). Eye. 1987;1:136-145.

SECTION EDITOR: W. RICHARD GREEN, MD