In a previous retrospective review,3
my colleagues and I described pulmonary cryptococcosis in HIV-seronegative patients. Our first challenge was to define infection vs colonization. The case definitions used in that report were as follows: (1) definite infection, the isolation of C neoformans in a respiratory specimen with radiographic evidence of disease and clinical symptoms without any other proven etiologies; (2) presumptive infection, the isolation of C neoformans in a respiratory specimen with radiographic evidence of disease, clinical symptoms, and concomitant respiratory pathogens or other noninfectious respiratory disease (bronchitis, aspiration pneumonia, bronchiectasis, interstitial pulmonary fibrosis, congestive heart disease, or connective tissue disease), so that one cannot solely attribute the patient’s presentation to cryptococcosis; and (3) colonization, the isolation of C neoformans in a respiratory specimen with (a) a normal chest radiograph, or (b) an asymptomatic state with abnormal chest radiograph, or (c) a postmortem confirmation of another etiology without evidence of cryptococcal disease. A disseminated disease was defined as an isolation of C neoformans in the blood, in sterile body fluid, or at an extrapulmonary site.