September 27, 2001

Gehrig's Fatal Nerve Disease Responds Positively to HIV Treatments

By Steve Sternberg USA TODAY

A pair of startling reports out Monday provide the first evidence that the AIDS virus, HIV, can cause a form of Lou Gehrig's disease that improves or disappears with treatment.

The finding promises to resurrect a decades-old debate about whether viruses play a role in Lou Gehrig's disease, and to raise new questions about whether antiviral drugs can successfully treat the illness, which also is known as amyotrophic lateral sclerosis (ALS). 

Following anti-HIV treatment, two French patients and a 32-year-old woman from New York recovered completely from the nerve disease, which was thought to be fatal in all cases, doctors report in today's Neurology. 

''Treat their HIV infection, and the ALS goes away,'' marvels Burk Jubelt of the State University of New York Upstate Medical University in Syracuse, who wrote an accompanying editorial.

French researchers at the Adolphe de Rothschild Foundation in Paris identified six cases of apparent ALS among 17,000 people infected with HIV over a 13-year period. Doctors at Beth Israel Hospital in New York reported on a seventh case. All but one of the patients benefited from anti-HIV therapy; the remaining patient's condition stabilized, French researchers say. 

Daniel MacGowen, author of the case report from New York, says his patient's recovery seemed almost miraculous. ''She went from walking to not being able to turn over in bed in a matter of months,'' he says. ''Six months after we put her on this medicine, like Lazarus, this woman walks into the clinic wearing leg braces. She's doing great. I've never seen anything like this before.''

About 20,000 people in the USA have ALS, and an additional 5,000 cases are diagnosed each year. No one knows what causes ALS or why sufferers die. One treatment, riluzole, can slow but not stop the disease from progressing.

MacGowen says his patient's illness isn't identical to classic ALS, though it is similar. It progressed far more rapidly than typical ALS, and doctors found other subtle differences on medical tests. These findings may mean the ailment is a rare, newly recognized HIV complication that is unrelated to ALS.

But that may not matter when it comes to treating ALS patients, MacGowen says. Potent AIDS drugs called protease inhibitors work partly by preventing certain white blood cells from dying. He says the drugs may have the same effect on nerve cells, somehow keeping them alive. To explore this theory, MacGowen plans to test a protease inhibitor, called indinavir, in 40 ALS patients who are HIV free. 

MacGowen says previous studies of the role viruses play in ALS have proved inconclusive, but doctors now have more sophisticated research tools than they did many years ago, ''the last time anyone looked for viruses'' in ALS.

Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, calls the study ''interesting,'' because treating HIV, which doesn't infect nerves, shouldn't affect the course of a nerve disease. But other studies indicate that HIV does somehow indirectly affect nerves. Children with HIV have been known to develop terrible nervous system ailments that disappear with treatment. 

Because HIV doesn't directly attack nerve cells, researchers believe the virus may instead weaken the immune system so that it can no longer suppress other, undetected microbes that directly damage nerves. Another theory holds that the HIV-damaged immune system somehow wreaks havoc among crucial nerve centers in the brain.