DISSEMINATED INFECTION WITH MYCOBACTERIUM -AVIUM COMPLEX IN PATIENTS WITH HIV-INFECTION

Epidemiology: Disseminated MAC-infection is one of the most frequent o pportunistic infections occuring in HIV-infected patients. Severely im munocompromised patients with CD4-counts < 50/mu l are at greatest ris k for the disease. Survival of untreated infection is very poor (5 to 6 months). With therapy survival is prolonged by about 4 months. Clini cal Presentation and Diagnostic Procedures: The leading symptom of MAC -infection is fever eventually accompanied by weight lost, night sweat s, enlarged lymph nodes, hepatosplenomegaly, abdominal pain and anemia . Blood cultures are very sensitive and the most appropriate examinati on. Other diagnostic procedures include bone marrow cultures, biopsies of the gastrointestinal tract, lymph nodes and the liver. Detection o f MAC in sputum and stool samples only proves colonisation but not dis semination. However, colonisation of the gastrointestinal tract freque ntly precedes disseminated disease. Therapy: Combination of clarithrom ycin, rifabutin and ethambutol has proven to be the most efficacious t herapy and therefore has to be considered as standard therapy for diss eminted MAC-infection, Problems most frequently encountered with this medication include uveitis (rifabutin), gastrointestinal disturbances (clarithromycin) and leucopenia (rifabutin) as well as drug interactio ns with protease-inhibitors (rifabutin). Prophylaxis: Clarithromycin, rifabutin and azithromycin given as primary prophylaxis can diminish t he risk of disseminated MAC-infection. Although a survival benefit has been seen with clarithromycin, primary prophylaxis of MAC-infection. is not standard care in many centers. Reasons to withhold MAC-proyhyla xis include lower incidence rates in some countries as well as possibl e side effects and drug interactions. Conclusion: Disseminated MAC-inf ection is a frequent opportunistic disease in HIV-infected persons who are severely immunocompromised. Antibiotic combination therapy with c larithromycin, rifabutin and ethambutol improves clinical symptoms and survival. Primary prophylaxis with different regimens is efficacious but the specific epidemiologic situation in each country has to be con sidered.