mac: pathogenesis and treatment.

NLM AIDSLINE MAC: pathogenesis and treatment. Benson CA; Rush Medical College, Chicago IL.
November 30, 1996

3rd Conf Retro and Opportun Infect. 1996 Jan 28-Feb 1;:166. Unique Mac disease results from a complex interplay between virulence characteristics of MAC and host immune responses. Following inhalation of ingestion of MAC, virulent strains are able to adhere to and invade mucosal epithelial cells. Fibronectin, mannosyl-fucosyl and CR1 or CR3 receptor interactions, deposition of C'3, and activation of the alternate complement pathway, play key roles in the subsequent binding and update of MAC macrophages. MAC may resist oxidative killing by production of superoxide dismutase or inhibition of phagosome-lysosome fusion and acidification. IFN-gamma, TNF-a, GM-CSF, IL-1-a, IL-6, IL-10, IL-12 and TGF-beta each influence MAC pathogenesis. IL-12 indirectly affects MAC by stimulating IFN-gamma, GM-CSF and TNF-a production. IFN-gamma or TNF-a +/- other cytokines decrease intra-celluar growth of MAC. GM-CSF activates macrophages and with TNF-a reduces intracellular growth of MAC. IL-1-a, IL-6, IL-10 and TGF-beta increase intracellular MAC growth: IL-6 may down-regulate TNF receptor expression. After infection unrestricted MAC replication results in an initial, often asymptomatic mycobacteremia: dissemination leads to a heavy tissue burden with sustained bacteremia and overt symptoms. MAC disease should be treated with at least two drugs. Clarithromycin (CLA) or azithromycin are active primary drugs; ethambutol (EMB) added to CLA appears to delay the emergence of resistance. CLA regimens are superior to non-macrolide regimens, clofazimine appears to have minimal effect, and rifabutin, when added to CLA and EMB may enhance their efficacy. A response can be expected within 2-6 weeks. Relapse is common; the most effective salvage therapy or the role of immunomodulators is unclear. Anti-Infective Agents/ADMINISTRATION & DOSAGE/THERAPEUTIC USE Azithromycin/ADMINISTRATION & DOSAGE/THERAPEUTIC USE Clarithromycin/ADMINISTRATION & DOSAGE/THERAPEUTIC USE Complement Pathway, Alternative Cytokines/METABOLISM Ethambutol/ADMINISTRATION & DOSAGE/THERAPEUTIC USE Human Macrophages/MICROBIOLOGY Mycobacterium avium Complex/METABOLISM/PATHOGENICITY Mycobacterium avium-intracellulare Infection/DRUG THERAPY/ *ETIOLOGY ABSTRACT

Most Read: Latest Added Related Topics White House LGBT Conference on HIV/AIDS UNITED STATES: White House in Atlanta: LGBT AIDS Conference No more single-theme conferences: global HIV prevention conference planned FHI 360 Senior Scientist Lut Van Damme Receives International Microbicide Conference Lifetime Achievement Award Photographs from A Day with HIV Now Online Equatorial Guinea Ministry of Health and Social Welfare and UNICEF Refute Erroneous AIDS Prevalence Figures Bulgaria urges Libya to investigate AIDS nurses case Engineers enter fight against AIDS in Africa Gilead’s Complera® Non-Inferior to Atripla® Among Treatment-Naive HIV Patients UN chief Ban calls world leaders to end Aids by 2020 ARIZONA: Routine Skin Testing Available Again at Tuberculosis Clinic Starting May 20 NORTH DAKOTA: Officials: 26 Tuberculosis Cases from Grand Forks Outbreak AUSTRALIA: HIV Rates Triple in the Northern Territory in Just 12 Months ARIZONA: Parsons Foundation Gives $3 Million to Southwest Center for HIV/AIDS UNITED STATES: Triple Therapy for Hepatitis C is Effective After Liver Transplantation, but Side-Effects Are Common CANADA: Nunavut Uses Comic Book to Do Sex Education NEW HAMPSHIRE: State Health Officials Urge Hepatitis Testing UNITED STATES: Hepatitis C Testing for People Born Between 1945 and 1965 People with HIV pay more for life insurance – if they can get it (South Africa)Uganda: Gov't Urged to Levy a Tax On Alcohol to Fund HIV Viet Nam: South-South learning helps prepare for sustainable provision of AIDS treatment China and Africa Discuss Health Treatment Problems Simpler ARV treatment begins in Eastern Cape AFRICA: Less-Used HIV Treatment for African Children More Effective CANADA: Drug-Resistant Gonorrhea Prompts New Treatment Guidelines in Ont. Less-Used HIV Treatment for African Children More Effective The Next Step in Drug Treatment Boehringer Ingelheim's Faldaprevir-Based Treatment Regimen Achieved Viral Cure in up to 80 Percent of Patients with Hepatitis C in Phase 3 Pivotal Trial AHF Applauds WHO Decision to Initiate HIV Treatment Earlier Call for urgent scale up of access to treatment
Information in this article was accurate in November 30, 1996. The state of the art may have changed since the publication date. This material is designed to support, not replace, the relationship that exists between you and your doctor. Always discuss treatment options with a doctor who specializes in treating HIV.