The evolution of pulmonary cryptococcosis: clinical implications from a study of 41 patients with and without compromising host factors.

Over 14 years 41 patients were diagnosed as having pulmonary cryptococcosis. Cryptococcus neoformans remained localized to the lung in 12 cases and disseminated in the remaining 29. Thirty-four patients were compromised hosts. Disseminated disease developed in 28 of these 34, and four of these 28 patients with disseminated disease presented with concomitant pulmonary and meningeal infections. In all the remaining 24 central nervous system involvement developed 2 to 20 weeks after the finding of an abnormal chest roentgenogram. Seven patients were normal hosts, and in six of these cases disease remained localized to the lung. Four important conclusions were drawn from this study: pulmonary cryptococcosis is rarely considered in the differential diagnosis of an abnormal chest roentgenogram, thereby leading to missed diagnoses and therapeutic errors; the natural history of untreated pulmonary cryptococcosis in compromised hosts is extrapulmonic dissemination; compromised hosts with pulmonary cryptococcosis should receive antifungal therapy because of a high propensity for dissemination; and normal hosts in whom dissemination has been excluded generally do not need antifungal therapy.