Low prevalence of human metapneumovirus and human bocavirus in adult immunocompromised high risk patients suspected to suffer from Pneumocystis pneumonia.

BACKGROUND: Novel respiratory viruses were discovered in the last years predominantly in children. Until now information on newly identified respiratory viruses in immunosuppressed adult patients is limited. Here we investigated immunocompromised adults with suspected Pneumocystis jirovecii pneumonia (PCP) for new respiratory viruses.

METHODS: Bronchoalveolar lavage (BAL) samples of 128 patients with atypical pneumonia (HIV-infected n=50, hematological malignancy n=51, immunosuppressive treatment n=27) were prospectively evaluated for P. jirovecii and retrospectively for new respiratory viruses (HMPV, HBoV, HCoV-NL63/SARS/HKU1).

RESULTS: P. jirovecii was detected in 26/128, bacteria in 10, fungi in four, Influenza A in two patients. Novel respiratory viruses were found in only two/128 patients with hematological malignancy, of those one patient with HBoV-infection and one with HMPV-infection, respectively. No pathogens were detected in 82/128 patients. The one patient with detection of hMPV and clinical diagnosis of atypical pneumonia died of pulmonary failure.

CONCLUSION: Human bocavirus and human metapneumovirus are rarely involved in atypical pneumonia in immunocompromised adult patients with suspected PCP, but may contribute to severe respiratory failure.