[Retinal capillary angioma. Clinical and molecular genetic studies]

Capillary retinal angiomas are rare vascular tumors that frequently occur in von Hippel-Lindau syndrome (vHL) but may also be sporadic. In all patients presenting with this tumor a thorough search for other vHL-associated lesions must be performed. After identification of the vHL gene on the short arm of chromosome 3 (3p25-26), the diagnosis is supported by molecular genetic analysis.

In 20 patients with retinal angioma a clinical search for other manifestations of vHL was performed. In 5 patients only one angioma was present. In all patients molecular genetic tests for a mutation of the vHL gene were performed by SSCP and direct sequencing.

In 16 (80%) patients vHl was present, and in 15 it could be diagnosed by clinical findings or a positive family history. Organ lesions in vHL patients were CNS hemangioblastoma in 10 (63%), pancreatic cysts in 7 (43%) and renal cysts in 7 (43%) patients. In two patients (13%) renal carcinoma could be detected; in one patient a pheochromocytoma was present. A mutation could be detected in all 15 patients with clinically confirmed vHL. In three patients a new mutation of vHL disease was diagnosed genetically. In one of these patients a single retinal angioma was the only sign of vHL.

In patients presenting with capillary retinal angioma a careful search for other vHL lesions has to be performed. A mutation of the vHL gene can be detected in the majority of patients; thus, molecular genetic testing is a powerful tool for diagnosis and detection of asymptomatic gene-carriers.