Mycobacterium avium complex prophylaxis

Rifabutin is a rifamycin used for prophylaxis against Mycobacterium avium complex infections in patients with low CD4 count. As with rifampicin it induces hepatic enzymes, although to a lesser extent than rifampicin, and the effectiveness of some drugs including oral contraceptives may be reduced. 

Mycobacterium avium complex (MAC) prophylaxis PO 500 mg twice a day MAC treatment PO 500 mg twice a day in combi nation. 

Faris MA, Raasch RH, Hopfer RL, Butts JD. Treatment and prophylaxis of disseminated Mycobacterium avium complex in HIV-infected individuals. Ann Pharmacother... 

The incidence of disseminated Mycobacterium avium complex (MAC) infection has increased dramatically with the AIDS epidemic. Treatment regimens for patients with a positive culture for MAC from a sterile site should include two or more drugs, including clarithromycin. Prophylaxis against disseminated MAC should be considered for patients with a CD4 cell count of less than 50 X 10 /1 (5). In a randomized, open trial in 37 patients with HIV-associated disseminated MAC infection, treatment with clarithromycin -I- ethambutol produced more rapid resolution of bacteremia, and was more effective at sterilization of blood cultures after 16 weeks than azithromycin -I- ethambutol (6). 

Masur H. Recommendations on prophylaxis and therapy for disseminated Mycobacterium avium complex disease in patients infected with the human immnnodeficiency virus. Public Health Service Task Force on Prophylaxis and Therapy for Mycobacterium avium Complex. N Engl J Med 1993 329(12) 898-904. 

Pierce M, Crampton S, Henry D, et al. A randomized trial of clarithromycin as prophylaxis against disseminated Mycobacterium avium complex infections in patients with advanced acquired immunodeficiency syndrome. N Engl J Med 1996 335 383-391. 

Rifabutin is a newly marketed, semisynthetic antimycobac-terial agent similar to rifampicin (rifampin) in structure and activity. However, rifabutin has important pharmacokinetic differences compared with rifampicin. The clinical effectiveness of rifabutin for prophylaxis of disseminated Mycobacterium avium complex infections has recently been demonstrated in HIV-positive patients with low CD4 counts. 

Pierce, M., Crampton, S., Henry, D., Heifets, L., LaMarca, A., Montecalvo, M., Wormser, G. R, Jablonowski, H., Jemsek, J., Cynamon, M., Yangco, B. G., Notario, G., and Craft, J. C. (1996). A randomized trial of clarithromycin as prophylaxis against disseminated Mycobacterium avium complex infection in patients with advanced acquired immunodeficiency syndrome. N. Engl. J. Med. 335, 384-391. 

Freedberg, K. A., Cohen, C. J., and Barber, T. W. (1997). Prophylaxis for disseminated Mycobacterium avium complex (MAC) infection in patients with AIDS A cost-effectiveness analysis. J. Acquir. Immune Defic. Syndr. Hum. Retroviral. 15, 275-282. 

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