Asymptomatic carriage of Pneumocystis jirovecii and cytomegalovirus in lungs of immunocompetent patients.

PURPOSE: Pneumocystis jirovecii (PCP) and cytomegalovirus (CMV) are opportunistic pathogens which cause lung infection in immunocompromised individuals. However, scarce data are available regarding the carriage of CMV or PCP in immunocompetent, non critically ill patients. The purpose of this study was to evaluate the prevalence of PCP and CMV in broncholaveolar lavage of adult immunocompetent, non critically ill patients.

METHODS: BAL fluids from immunocompetent patients who underwent bronchoscopy were analyzed by polymerase chain reaction (PCR) for CMV and PCP DNA. We tested CMV antibodies in serum. In patients with positive CMV DNA in lavage fluid, we further analyzed peripheral blood for the presence of CMV DNA.

RESULTS: Ninety three patients were included. We did not detect PCP DNA in BAL in any patient. CMV DNA was found in BAL of 5 of 86 CMV IgG positive patients (5.8 %). Patients who were positive for CMV did not differ from patients with negative PCR for CMV regarding demographic and clinical features.

CONCLUSION: We did not find PCP colonization in our cohort of patients. However, we found significant prevalence of CMV DNA in BAL from immunocompetent patients, with no evidence of acute CMV infection. This finding may represent colonization by CMV in immunocompetent, non-critically ill individuals.