Reactivation of <i>Mycobacterium avium</i> complex in the lungs of mice following immunosuppression.

<p>Mice were infected with approximately 500–1,000 CFUs of each MAC strain for 10 weeks and treated for 6 weeks with clarithromycin and rifampicin. Following the antibiotic regimen, mice were treated with immunosuppressants. A: MAV SM#1 represents the reactivation model of <i>M</i>. <i>avium</i> strains. B: MI SM#42 represents the reactivation model of <i>M</i>. <i>intracellulare</i> strains. Both graphs depict a dramatic decrease in bacterial counts, which were undetectable after antibiotic treatment and a dramatic increase after sulfasalazine treatment. For A and B, CFUs at 35 weeks represent the sulfasalazine-treated group. C and D represent the bacterial counts of individual murine lungs infected with MAV SM#1 and MI SM#42, respectively. Each group exhibited different reactivation levels according to the immunosuppressant used. The dashed line represents the detection limit of bacterial counts. Red arrows represent undetectable bacilli in each mouse. For A and B, the data are the median ± interquartile range (IQR).