Restored immunity protects AIDS patients from opportunistic infection

April 11, 2000

A new study led by a Columbia researcher demonstrates that HIV-infected patients who respond well to antiretroviral drugs can safely forgo antibiotics to prevent certain opportunistic infections.

Dr. Wafaa M. El-Sadr, chief of the Division of Infectious Disease at the Harlem Hospital Center and a professor of clinical medicine at Columbia University's College of Physicians & Surgeons, led the study, which included patients at 15 centers nationwide. The report of the study will appear in the April 13 issue of the New England Journal of Medicine.

According to U.S. Public Health Service guidelines, HIV-infected patients with CD4+ cell counts below 50 per cubic millimeter of blood should have antibiotic treatment to prevent Mycobacterium avium complex (MAC) disease, a serious and potentially fatal condition. CD4+ cells are immune system cells that fight infection and are attacked by the HIV virus. Levels of these cells are a measure of the strength of a person's immune system and the severity of HIV infection.

Dr. El-Sadr and her colleagues launched the study to determine whether prophylaxis is still necessary for HIV patients whose CD4+ cell counts rise above 100 per cubic millimeter after treatment with antiretroviral therapy.

The researchers enrolled 520 patients with a median CD4+ cell count of 230 per cubic millimeter of blood. All of the study participants had CD4+ levels below 50 at some point in the past but had two consecutive CD4+ cell counts of 100 or more since beginning antiretroviral therapy.

Half of the patients took azithromycin each week, while half took a placebo. Patients were followed for an average of 12.7 months. None developed MAC disease during the study. Three patients taking azithromycin and five patients taking the placebo developed bacterial pneumonia. During the study, 19 patients taking azithromycin and three of the patients in the placebo group dropped out because of adverse effects of the drug.

Dr. El-Sadr and colleagues describe several benefits that would result from allowing this group of HIV-infected patients to defer taking prophylactic antibiotics. Studies have shown that people who take antibiotics regularly are more likely to develop infections with antibiotic-resistant bacteria. Also, patients on antiretroviral therapy for HIV infection already take several drugs, and adding one more to the regimen increases the risk of drug interaction and also makes following treatment more difficult.

Infectious disease and immunology experts had questioned whether CD4+ cells reconstituted by antiretroviral therapy would be as protective against infection as normal CD4+ cells. This study suggests that antiretroviral therapy does reconstitute protective immunity, according to Dr. El-Sadr. "The event rate for all opportunistic infections was actually pretty low across the board," she explains. "The lower event rate suggests that these individuals are protected against these complications."

The study was funded by a grant from the National Institute of Allergy and Infectious Diseases.
-end-


Columbia University Medical Center

Related Immune System Articles from Brightsurf:

How the immune system remembers viruses
For a person to acquire immunity to a disease, T cells must develop into memory cells after contact with the pathogen.

How does the immune system develop in the first days of life?
Researchers highlight the anti-inflammatory response taking place after birth and designed to shield the newborn from infection.

Memory training for the immune system
The immune system will memorize the pathogen after an infection and can therefore react promptly after reinfection with the same pathogen.

Immune system may have another job -- combatting depression
An inflammatory autoimmune response within the central nervous system similar to one linked to neurodegenerative diseases such as multiple sclerosis (MS) has also been found in the spinal fluid of healthy people, according to a new Yale-led study comparing immune system cells in the spinal fluid of MS patients and healthy subjects.

COVID-19: Immune system derails
Contrary to what has been generally assumed so far, a severe course of COVID-19 does not solely result in a strong immune reaction - rather, the immune response is caught in a continuous loop of activation and inhibition.

Immune cell steroids help tumours suppress the immune system, offering new drug targets
Tumours found to evade the immune system by telling immune cells to produce immunosuppressive steroids.

Immune system -- Knocked off balance
Instead of protecting us, the immune system can sometimes go awry, as in the case of autoimmune diseases and allergies.

Too much salt weakens the immune system
A high-salt diet is not only bad for one's blood pressure, but also for the immune system.

Parkinson's and the immune system
Mutations in the Parkin gene are a common cause of hereditary forms of Parkinson's disease.

How an immune system regulator shifts the balance of immune cells
Researchers have provided new insight on the role of cyclic AMP (cAMP) in regulating the immune response.

Read More: Immune System News and Immune System Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.