Some HIV patients can stop taking prophylaxis against infections

Patients infected with HIV whose immune systems have responded well to combination antiretro-viral treatment can stop taking prophylaxis for Pneumocystis carinii pneumonia, a study in the New England Journal of Medicine has found (1999;340:1301-6).

The study, conducted by Dr Hansjakob Furrer and colleagues from the Bern Hospital in Switzerland, followed 262 patients who had stopped taking the prophylaxis. While the patients were on triple therapy, their CD4 counts rebounded to at least 200 3 10⁶ cells/l for three months or longer.

Two patients died during the 11 months of follow up, and nine had to start taking prophylaxis again because they were not responding to antiretroviral treatment. But none of the remaining patients who had stopped the antibiotic prophylaxis contracted Pneumocystis carinii pneumonia during follow up.

Ten years ago, the United States Public Health Service recommended that patients with low blood counts resulting from HIV take a lifelong regimen of trimethoprim-sulfamethoxazole to protect themselves from contracting pneumonia. Until now it was unclear whether primary prophylaxis for Pneumocystis carinii pneumonia could be discontinued by patients with HIV who had successfully been treated with combination antiretroviral treatment.

The study confirms that antiretroviral regimens containing protease inhibitors have the ability to restore immune function enough to obviate the need for lifelong prophylaxis against some opportunistic infections.

In an accompanying editorial, Dr Henry Masur of the National Institutes of Health and Dr Jonathan Kaplan of the Centers for Disease Control and Prevention, noted that although the antibiotic prophylaxis against Pneumocystis carinii pneumonia is inexpensive, withdrawing treatment could help simplify the complicated drug regimens that many patients currently use (New England Journal of Medicine 1999;340:1356-7).

“The discontinuation of an inexpensive drug that is taken once daily may seem trivial given the complexity of most HIV regimens, but such a step would not only simplify the regimen… but also provide a psychological benefit, by affirming that immunologic function is improved.”