The acronym COACH describes a syndrome associated with:
- C - cerebellar vermis defect (Joubert syndrome)
- O - oligophrenia
- A - ataxia
- C - coloboma
- H - hepatic fibrosis
There only as little as 11 cases having been reported in the English medical literature.
- delayed psychomotor development.
- visual difficulty.
- hepatomegaly, elevated levels of liver enzymes (hepatic fibrosis).
- cerebelar ataxia.
- dysmorphic features such as hypertelorism and ptosis.
- episodic hyperpnea.
Presently, no genes have been identified that cause COACH syndrome specifically. It is likely that alterations in multiple genes cause this condition.
- increased echogenicity of the liver parenchyma, collateral vessels and splenomegaly due to portal hypertension.
- increased echogenicity of the kidneys' pyramids.
- the sonographic features of eye coloboma include a defect in the retina with an obliquely posterior herniation of the vitreus body; retinal detachment.
- Absence or hypoplasia of the vermis ; the cerebellar hemispheres appose one another because of the lack of the vermis ; the superior cerebellar peduncules are prominent because they have a horizontal course and are well delineated by CSF.
- may show evidence of hepatic fibrosis and portal hypertension
- may show evidence of polycystic kidney disease.
- may show chorioretinal colobomas.
Treatment and prognosis
The main clinical problem for patients with COACH syndrome is progressive portal hypertension and liver failure. Treatment aims to reduce symptoms and prevent complications.
The lack of oculomotor abnormalities and the episodic hyperpnea distinguish this syndrome from Joubert's syndrome.
- 1. Barkovich A. James. Pediatric neuroimaging. Lippincott Williams & Wilkins, 2005. ISBN: 0781757665, 9780781757669.
- 2. Verloes A, Lambotte C. Further delineation of a syndrome of cerebellar vermis hypo/aplasia, oligophrenia, congenital ataxia, coloboma, and hepatic fibrosis. Am. J. Med. Genet. 1989;32 (2): 227-32. Am. J. Med. Genet. (abstract) - doi:10.1002/ajmg.1320320217 - Pubmed citation
- 3. Barzilai M, Ish-Shalom N, Lerner A et-al. Imaging findings in COACH syndrome. AJR Am J Roentgenol. 1998;170 (4): 1081-2. AJR Am J Roentgenol (citation) - Pubmed citation