Adjuvant interferon gamma in patients with pulmonary atypical Mycobacteriosis: a randomized, double-blind, placebo-controlled study

ABSTRACT

Background High antibiotic resistance is described in atypical Mycobacteriosis, mainly by Mycobacterium avium complex (MAC). MethodsA randomized, double-blind, placebo-controlled clinical trial was carried out in two hospitals to evaluate the effect of interferon (IFN) gamma as immunoadjuvant to chemotherapy on patients with atypical mycobacteria lung disease. Patients received placebo or 1 × 106 IU recombinant human IFN gamma intramuscularly, daily for one month and then three times per week up to 6 months as adjuvant to daily oral azithromycin, ciprofloxacin, ethambutol and rifampin. Sputum samples collection for direct smear observation and culture as well as clinical and thorax radiography assessments were done during treatment and one year after. Cytokines and oxidative stress determinations were carried out in peripheral blood before and after treatment. Results Eighteen patients were included in the IFN group and 14 received placebo. Groups were homogeneous at entry; average age was 60 years, 75 percent men, 84 percent white; MAC infection prevailed (94 percent). At the end of treatment, 72 percent of patients treated with IFN gamma were evaluated as complete responders, but only 36 percent in the placebo group. The difference was maintained during follow-up. A more rapid complete response was obtained in the IFN group (5 months before), with a significantly earlier improvement in respiratory symptoms and pulmonary lesions reduction. Disease-related deaths were 35.7 percent of the patients in the placebo group and only 11.1 percent in the IFN group. Three patients in the IFN group normalized their globular sedimentation rate values. Although differences in bacteriology were not significant during the treatment period, some patients in the placebo group converted again to positive during follow-up. Significant increments in serum TGF-beta and advanced oxidation protein products were observed in the placebo group but not among IFN... (AU)