Mycobacterium avium complex infections disseminated

Defective IL-12 production is associated with increased susceptibility to infection (e.g., familial disseminated Mycobacterium avium complex infection, T. cruzi infection, and human visceral leishmaniasis), a finding that supports the critical role of this cytokine in host defense and in the regulation of the cellular immune responsed The loss of immune function following infection with HIV may resrdt from altered production of immunoregulatory cytokines, such as IL-10 and IL-12. It was suggested that monocytes from HIV-positive individuals secrete decreased amounts of IL-12, which may lead to the development of Th2 type of responses characterized by high IL-10 secretion and immune dysfunction/ ... 

Frucht DM, Holland SM. Defective monocyte costimulation for IFN-y production in familial disseminated Mycobacterium avium complex infection abnormal IL-12 regulation. J Immunol 1996 157 411-6. 

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. 

Mycobacteria of the Mycobacterium avium complex are implicated in disseminated bacterial infections in AIDS patients. RFLP studies followed by hybridization with radiolabeled probe specific for an insertion sequence in M. avium (IS 1311) have been useful for typing M. avium stains (R2). A variety of molecular techniques are available for the diagnosis of Chlamydia trachomatis infection. In addition to PCR, a method based on the ligase chain reaction has also been found to be sensitive to the detection of C. trachomatis infection in urine specimens collected from male and female subjects (VI). The differentiation between low-risk genotypes of human papilloma virus (HPV 6 or 11) from genotypes of high... 

Prevention of disseminated Mycobacterium avium complex (MAC) infections 1,200 mg taken once weekly. 

The aminoglycoside (see Section II.c) streptomycin was the first antimycobacterial antibiotic. It has activity against extracellular mycobacteria with a high growth rate. The macrolide antibiotics azithromycin and clarithromycin (see Section Il.d.l) were approved for the treatment of disseminated mycobacterial infections due to Mycobacterium avium complex. 

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

Organisms of the Mycobacterium avium complex (MAC) commonly cause disseminated bacterial infection among patients with AIDS. There is evidence that immunoprophylaxis against MAC infection may be possible. A heat-killed Mycobacterium vaccae vaccine was given in a three-dose schedule to 12 HIV-infected adults with CD4 cell counts below 300 x 10 /1 (107). The vaccine was well tolerated and produced detectable immunological responses in 3 of 11 subjects who completed the trial. 

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. 

Benson CA, Williams PL, Currier IS, et al. A prospective, randomized trial examining the efficacy and safety of clarithromycin in combination with ethambutol, rifabutin, or both for the treatment of disseminated Mycobacterium avium complex disease in persons with acquired immunodeficiency syndrome. CUn Infect Dis 2003 37 1234-1243. 

Clarithromycin is an H. pylori agent/macrolide, which inhibits microbial protein synthesis. Clarithromycin is indicated in the treatment of infections of the respiratory tract, skin and skin structure treatment of disseminated atypical mycobacterial infections caused by susceptible strains of specific microorganisms and prevention of disseminated Mycobacterium avium complex disease in patients with advanced HIV infection. Clarithromycin in combination with omeprazole is indicated in the treatment of patients with an active duodenal ulcer associated with H. pylori infection. In children it is used in acute otitis media. Macrolides are erythromycin, clarithromycin, and azithromycin. 

Ostroff, S. M., Spiegel, R. A., Feinberg, J., Benson, C. A., and Horsburgh, Jr., C. R. (1995). Preventing disseminated Mycobacterium avium complex disease in patients infected with human immunodeficiency virus. Clin. Infect. Dis. 21, S72-S76. 

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. 

Azithromycin, though less active against streptococci and staphylococci than erythromycin, is far more active against respiratory infections due to Haemophilus influenzae and Moraxella catarrhalis. Except for its cost, it is now the preferred therapy for urethritis caused by Chlamydia trachomatis. Its activity against Mycobacterium avium intracellulare complex has not proven to be clinically important, except in AIDS patients with disseminated infections. 

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