Ask the Experts

[Testing Children]    

[VHL and Smoking]   

[Families from Germany]  

published June 1993, with notes to update the information as of December 1997

Testing Children

Q: What should I do about testing my children? I don’t want to find out when they’re 12 that I should have had them tested at age 8. — Mary Ellen T., Massachusetts

A: Children born to a parent with von Hippel-Lindau disease are at a 50% risk for inheriting the gene defect. Therefore, early monitoring is recommended. The pediatrician should be alerted to the family history. Careful ophthalmologic examinations should be started at around 4 years of age and be repeated annually thereafter. Each year the child should have a careful physical examination with special attention to the blood pressure and neurologic status.

At around ages 10 to 12 it is reasonable to begin screening of the central nervous system by CT scan or MRI of the head, and MRI of the upper spinal cord. This also should be repeated every 1-2 years thereafter. Any child who develops unexplained headaches, flushing, or high blood pressure should have a urine test to assess for pheochromocytoma. This is particularly true in families in which other members with von Hippel-Lindau disease have had pheochromocytomas. Imaging of the intra-abdominal organs should be offered at around age 18 years and annually thereafter.

These are general guidelines. It is important to know that in individual cases, physicians may choose to perform different tests or at different ages.

In some families with a sufficient number of affected family members, DNA studies for presymptomatic diagnosis may be an option. Depending on the outcome of the test, it may be possible to decrease the frequency of testing. In the future, it may be possible to eliminate testing completely for those whose DNA studies suggest they are unaffected.

-- Virginia V. Michels, M.D., Rochester, Minnesota

[Note 12/97: The accuracy of the DNA test no longer depends on the number of affected family members because there is now a direct DNA test which works in up to 93% of affected families depending on the technology in use at the testing center.   See DNA Testing.]

VHL and Smoking

Q: Is there any reason to believe that smoking is bad for people with VHL? -- Rachael M., Mass.

A: There is no comprehensive study of smoking and VHL, and there probably never will be because the VHL population is too small to do a controlled study. Smoking is not good for anyone because it increases the risk of lung disease, heart disease, and cancer. For that reason alone people with VHL and their families should refrain from smoking. Beyond that, however, there are some specific risk factors for people with VHL.

Chances are that at some point VHL patients will require at least one surgery. Smoking increases the risk of postoperative complications of the lungs (atelectasis, pneumonia, hypoxemia).

Secondly, smoking has been implicated as a risk factor for developing renal adenocarcinoma (kidney cancer). Since people with VHL are already at risk for renal adenocarcinoma, it is unreasonable to increase the risk even further.

My general advice to people with VHL is to avoid all medical problems except the unavoidable one (VHL) -- i.e., don't smoke, avoid obesity, eat properly, get plenty of exercise, avoid drug use (alcohol, cocaine, etc.), and make sure you have family and friends for support.

-- Col. James M. Lamiell, M.D., Fort Sam Houston, Texas

Families from Germany?

I finished reading the draft of the second issue of the VHL Family Forum. I was especially intrigued with the letter from Siobhan G., Michigan. I wonder if this family might have ancestors in the German Black Forest? I have seen a number of families with a lot of pheos and only a few CNS (spinal) hemangioblastomas.

-- Hartmut Neumann, M.D., Freiburg, Germany

[Note 12/97: Dr. Neumann has since published a study with colleagues in the United States about a set of families in Germany and Pennsylvania with a common ancestor.  It should be noted that Germany is not the only source of VHL.  VHL has been found in every ethnic group around the world.]