Diplopia as presenting sign of Turcot syndrome

Abstract

PurposeTo describe a patient with diplopia who was diagnosed with Turcot syndrome.MethodsA 10‐year old boy presented with a history of left‐sided sixth and seventh nerve palsy. He underwent imaging of the brain and colon, full ophthalmologic and genetic work‐up.ResultsA 10‐year old boy was referred with combined left‐sided sixth and seventh nerve palsy since one month without symptoms of raised intracranial pressure. BCVA was 6/6 in both eyes. Fundoscopy revealed bilateral, multiple, oval pigmented ocular fundus lesions (POFLs) in the 4 quadrants. These POFLs, together with the cranial nerve palsies raised the suspicion of Turcot syndrome, a familial neoplasia syndrome characterised by familial adenomatous polyposis and tumours of the central nervous system. Urgent MRI scan of the brain and stereotactic biopsy showed a primitive neuroectodermal tumour (PNET) at the pons. Coloscopy revealed multiple polyps. DNA analysis of the APC gene confirmed the clinical diagnosis of Turcot syndrome. The PNET was treated with combined radio‐ and chemotherapy. The patient underwent a prophylactic total colectomy as virtually all patients develop a carcinoma of the colorecal region if left untreated.ConclusionsDiplopia in childhood is rare and seldom innocuous. It requires a prompt and thorough diagnostic evaluation. The presence of POFLs should alert the clinician to the possiblility of Turcot syndrome. Recognition of this rare syndrome can lead to earlier diagnosis, which is vital to appropriate surveillance and early surgical intervention of the highly frequent neoplasias in Turcot Sydrome.