Pneumocystis f. sp. hominis causes pneumonia in immunocompromised persons.
In order to determine the types and distribution of P. carinii organisms wi
thin a single human lung, multiple samples were obtained from the lung of a
child who died of P. carinii pneumonia. P. carinii DNA was detected in all
of the samples and 2 different genotypes of P. carinii were identified, wi
th uneven distribution in the lung, demonstrating that infection of the hum
an lung is not necessarily clonal, and that different P. carinii genotypes
may predominate in different areas of the lung.