Outcomes and prognostic factors of non-HIV patients with pneumocystis jirovecii pneumonia and pulmonary CMV co-infection: A Retrospective Cohort Study

Background: Pneumocystis jirovecii pneumonia (PJP) and pulmonary cytomegalovirus (CMV) infection are common opportunistic infections among immunocompromised patients. However, few studies have evaluated their co-infection, especially among non-HIV patients. Therefore, we aimed to evaluate the outcomes and prognostic factors among non-HIV patients with PJP according to their CMV infection status. Methods: This retrospective study evaluated non-HIV patients who were diagnosed with PJP between January 2009 and January2016. The patients were classified and compared according to their pulmonary CMV infection status (positive infection: bronchoalveolar lavage fluid [BALF] CMV DNA loads of >500copies/mL). Results:Among 70 non-HIV patients with PJP, we identified 38 patients (54.3%) with pulmonary CMV infection. There was no significant difference in the mortality rates for the two groups (p = 0.15). Pulmonary CMV infection was significantly more common among patients who were receiving glucocorticoids and immunosuppressants, compared to corticosteroids only (p = 0.02). Pulmonary CMV infection was also significantly associated with severe dyspnea, a lower PaO2/FiO(2), and the presence of centrilobular nodules (p = 0.008). Higher CMV DNA loads in the BALF were positively associated with mortality (p = 0.012). Conclusions: Combined therapy using corticosteroids and other immunosuppressants may be a risk factor for pulmonary CMV co-infection among patients with PJP. In addition, CMV pneumonia should be considered when centrilobular nodules and/or severe hypoxemia are observed in non-HIV patients with PJP. Furthermore, antiviral treatment should be promptly initiated for patients with a high CMV DNA load in BALF, based on their poor prognosis.