False-Negative Nasopharyngeal Swab RT-PCR Assays in Typical COVID-19: Role of Ultra-low-dose Chest CT and Bronchoscopy in Diagnosis
  • Marco Marando
    General Internal Medicine, Ente Ospedaliero Cantonale, Lugano, Switzerland
  • Adriana Tamburello
    General Internal Medicine, Ente Ospedaliero Cantonale, Lugano, Switzerland
  • Pietro Gianella
    General Internal Medicine, Ente Ospedaliero Cantonale, Lugano, Switzerland; Pneumology, Ente Ospedaliero Cantonale, Lugano, Switzerland


Coronavirus, COVID-19, RT-PCR, ultra-low-dose chest CT, bronchoscopy


On 11 March 2020, the WHO declared COVID-19 a pandemic and global health emergency. We describe the clinical features and role of ultra-low-dose chest computed tomography (CT) and bronchoscopy in the diagnosis of coronavirus disease (COVID-19). In our patient, who was highly suggestive clinically and radiologically for COVID-19, we had two false-negative results for nasopharyngeal and oral swab reverse-transcriptase polymerase chain reaction (RT-PCR) assays for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Eventually, we confirmed the diagnosis using bronchoscopy and bronchoalveolar lavage (BAL).



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    Published: 2020-04-24
    Issue: 2020: Vol 7 No 5 (view)

    How to cite:
    Marando M, Tamburello A, Gianella P. False-Negative Nasopharyngeal Swab RT-PCR Assays in Typical COVID-19: Role of Ultra-low-dose Chest CT and Bronchoscopy in Diagnosis. EJCRIM 2020;7 doi:10.12890/2020_001680.