Von Hippel-Lindau Syndome Association of South Africa
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Von Hippel-Lindau Syndrome (VHL) is different from most other diseases in that it has no single primary symptom, it does not occur exclusively in one organ of the body, and it does not always occur in a particular age group. In the majority of cases it is an inherited disorder, where mostly benign tumours will develop because of abnormal growth of blood vessels in different organs of the body. Blood vessels normally branch out like trees; however in the case of people with VHL, knots of blood vessels (capillaries) sometimes occur in the brain, spinal cord, or retina. These knots are called angiomas, or hemangioblastomas. In other parts of the body the VHL tumours are called by other names. Cysts (fluid-filled sacs) may grow around the tumours which may exert pressure or create blockages that can cause symptoms. Cysts and tumours may also occur in the kidney, pancreas, and adrenal glands. The pressure that these tumours exert may in itself cause symptoms – they may press on nerve or brain tissue and cause symptoms such as headaches, problems with balance, or weakness of arms and legs. Tumours of the retina often grow around the periphery of the retina, away from the area of central vision and if not treated will eventually cause leakage/bleeding that can lead to serious vision damage or retinal detachment. VHL may be associated with a kind of tumour of the adrenal glands called a pheochromocytoma . These tumours produce “stress hormones” - adrenaline and noradrenaline - that are excreted into the bloodstream. The primary symptom is high or variable blood pressure that puts strain on the heart and vascular system and can cause heart attack or stroke.
People with VHL will usually experience one or more of the tumours shown in the figure. The frequency of the tumours and severity of the accompanying symptoms varies in different families. Early detection and careful monitoring are particularly important for these organ systems, usually with yearly CT or MRI, assisted by ultrasound scanning.VHL is caused by an alteration in one of your two copies of a gene referred to as the VHL gene. This altered gene can be inherited. Each child receives one gene of each pair from each parent. If one parent has an alteration ( mutation ) in the VHL gene, each child has a 50% chance of inheriting that faulty gene. One copy of the altered gene is sufficient to produce the disease. The only way to determine for sure that someone does / or does not have the altered VHL gene, is through DNA testing. With careful monitoring, early detection, and appropriate treatment, the most harmful consequences of this faulty gene can be greatly reduced, or in some cases even prevented.
For more information about VHL, Screening, DNA Testing, etc. contact the
Von Hippel-Lindau Syndome Association of South Africa
Markus Jansen van Vuuren [+27(0)82 779 5019] , markus.van.vuuren@telkomsa.net
Lizette Jansen van Rensburg [+27(0)12 319 2636], lizette.vanrensburg@up.ac.za
Visit www.vhl.org