Co-infection of Pneumocystis jirovecii pneumonia and pulmonary CMV in a infant with X-linked severe combined immunodeficiency.

We herein report a rare case of co-infection of Pneumocystis jirovecii pneumonia and pulmonary CMV in a 3-month-old infant with X-linked severe combined immunodeficiency, in which diagnostic clues were obtained from the bronchoalveolar lavage fluid. We focus on the value of cytological diagnosis of P. jirovecii pneumonia and pulmonary CMV in the bronchoalveolar lavage fluid. Recognizing morphological characteristics of these pathogenic microorganisms is important to get timely diagnosis and treatment for the patients. Furthermore, repeated severe infections in infants should remind us to screen for immunosuppressed states.