Occult COVID-19 in an immunosuppressed patient with migratory pulmonary infiltrates

The clinical presentation of SARS-CoV-2 infection is often more severe and persistent in immunosuppressed hosts. We present the case of a patient with mantle cell lymphoma under treatment with rituximab and ibrutinib who had multiple hospitalizations with pulmonary infiltrates following mild SARS-CoV-2 infection and repeated negative nasopharyngeal (NP) RT-PCR tests. SARS-CoV-2 was eventually detected in bronchoalveolar lavage fluid and the symptoms resolved after treatment with remdesivir. Whole genome sequencing was performed on the initial and final viral strains. Sequence comparison of the two showed that the final strain was derived from the former. Both were identical except for 15 differential single nucleotide polymorphisms, indicating that the virus had persisted undetected over time in this patient. Occult COVID-19 should be considered in immunocompromised patients with persistent respiratory symptoms despite negative NP RT-PCR tests. Systematic bronchoalveolar lavage fluid testing is recommended for accurate diagnosis and management.