NONTUBERCULOUS MYCOBACTERIAL INFECTION IN HIV-NEGATIVE PATIENTS RECEIVING IMMUNOSUPPRESSIVE THERAPY

The clinical significance of nontuberculous mycobacterial isolates and presentation of mycobacteriosis was compared in HIV-negative patients with or without preceding immunosuppression. Patients with nontubercu lous mycobacterial isolates (n = 139), mainly from the respiratory sys tem, were divided into three groups: those who had had previous immuno suppressive treatment (24%), those with other underlying diseases (54% ) and those without predisposing factors (22%). The distribution of my cobacterial species among the various patient groups was similar. The immunosuppressed patients fulfilled the criteria of the American Thora cic Society for clinical mycobacteriosis less frequently (18%) than th ose with other underlying diseases (32%) or without predisposing facto rs (45%), p = 0.07, the difference being more striking for patients wi th Mycobacterium avium complex isolates. This was partly due to the di fficulty in distinguishing the relevant symptoms from those caused by the underlying disease. The proportion of patients receiving antimycob acterial therapy differed similarly (18%, 21%, 45%, respectively). Amo ng the immunosuppressed patients, positive acid-fast smears were signi ficantly less common and polymicrobial infections, initial lymphocytop enia, fever and fatal outcome significantly more common. About half of the immunosuppressed patients died within one year. in order to bette r define patients requiring treatment, the criteria for localized myco bacteriosis among immunosuppressed patients should be reevaluated.