General
Most patients continue to grow poorly after birth. Genetics
Typical childhood-onset cerebroretinal microangiopathy with calcifications and cysts is caused by compound heterozygous mutations in the conserved telomere maintenance component 1 (CTC1) gene located in chromosome 17p.31. A late-onset phenotype without abnormal eye findings from a CTC1 mutation has been reported.CTC1 is a component of the CST complex, which is additionally composed of oligonucleotide/oligosaccharide-binding fold containing 1 (coded by OBFC1, also known as STN1) and telomerase capping complex subunit homolog 1 (coded by TEN1). CST complex is evolutionarily conserved. It binds to single-stranded DNA and associates with a fraction of telomeres, potentially protecting them. Pathophysiology
Angiomas and numerous abnormal, small, dilated telangiectatic vessels with thickened, sclerotic and calcified walls have been found in those brain areas which also show calcifications.By analogy to Coats disease, the exudative retinopathy is thought to result from breakdown of the blood-retinal barrier at the level of the vascular endothelial cell, resulting in leakage of blood plasma and lipid. Macrophages then migrate into the retina and subretinal space and digest the lipid. The accumulation of the proteinaceous exudate and macrophages thickens the retina, leading to exudative retinal detachment. Diagnosis
Clinical
The retinal changes are easily identified by ophthalmoscopy, which is performed under general anesthesia if the child is very young. The abnormal vessels are even better seen with fluorescein angiography. In advanced disease, glaucoma is diagnosed by measuring intraocular pressure and cataract by using slit lamp biomicroscopy.
Removal or enucleation of the eye is a last resort option if the eye already has become blind and painful.Repeated blood transfusions may be needed to control anemia, and thrombocytopenia can be managed with splenectomy. Prognosis
The neurological symptoms are progressive and can lead to severe spasticity, bulbar symptoms and dysarthria within one to two decades. The life span is shorter than normal. Death occurs between 2 and 30 years of age, depending on the severity of the syndrome. The immediate cause of death is pneumonia, fulminant intestinal bleeding or multiple organ dysfunction.If not treated, the retinal detachment can lead to ischemia and growth of new blood vessels over the iris and anterior chamber angle. This in turn can cause secondary glaucoma, cataract and, ultimately, blindness of the eye. Epidemiology
This syndrome is usually sporadic although families with two or more affected siblings of both sexes are known. History
A child who was eventually diagnosed with cerebroretinal microangiopathy with calcifications and cysts was first described in the literature in 1987. The disorder was suspected of being allelic with either the Revesz syndrome or leukoencephalopathy with calcifications and cysts.