Other common findings include diarrhea, malaise and anorexia. Laboratory data commonly reveal anemia and an elevated alkaline phosphatase. Common sites of involvement are the liver, lymph nodes, bone marrow, and GI tract. Rare manifestations have also been reported, including cutaneous disease, arthritis, sinusitis, orchitis, peritonitis, chylous ascites, appendicitis, endophthalmitis, choroiditis, pancreatitis, pericarditis, and meningitis. MAC becomes undetectable in the blood of most patients within three months after initiation of therapy.
Autopsy studies show that there is also a decreased mycobacterial load in tissues.
Patients with a known history of MAC were not included in the study. Patients received 1200 mg of azithromycin once a week or placebo. During a median follow-up of 16 months, only two cases of MAC were identified among 321 patients that were in the placebo group. No cases of MAC were identified in the 322 patients assigned to azithromycin. Both cases were atypical in that the infection was localized to the vertebral spine with negative blood cultures, similar to the patient being presented here.