Introduction:

hMPV is an emerging respiratory pathogen that has increasingly been recognized as a result of advancements in molecular diagnostics, thereby enhancing the detection and characterization of the agent. Those with a severe form of the disease are typically either paediatric/elderly or immunocompromised. hMPV-associated pneumonia in immunocompetent adults remains largely unexplored. This paper reviews a case of severe hMPV-associated community-acquired pneumonia in an immunocompetent adult and examines different chest CT findings in comparison to those in respiratory syncytial virus infections.

Methods:

We describe a case of 68-year-old immunocompetent male who had hMPV-induced CAP that was confirmed by multiplex RT-PCR. The etiology of the imaging findings is determined. Moreover, the study retrospectively assessed CT-scans of 10 hMPV-positive patients presenting with pulmonary symptoms. Comparing them with those from 13 patients with RSV-related pneumonia can help outline imaging differences and establish a time course of the hMPV-related pneumonia.

Results/Discussion:

The case showed bilateral ground-glass opacities and consolidations consistent with viral pneumonia. Early molecular diagnostics allowed for precise pathogen identification, guiding appropriate treatment and reducing unnecessary antibiotic use. Retrospective analysis demonstrated that hMPV pneumonia typically exhibits asymmetric findings, including ground-glass opacities, consolidations, nodular opacities, and bronchial wall thickening. Conversely, RSV pneumonia showed more symmetric bilateral interstitial involvement. Over time, hMPV-related interstitial pneumonia transitioned into bronchitis or bronchiolitis before resolving.

These findings highlight the need for hMPV-specific diagnostic testing and imaging in clinical workflows, which will improve management and reduce inappropriate antibiotic usage. Further research is necessary to better differentiate hMPV and RSV, guiding prevention and therapeutic strategies.