tetano
Editor, Senior Moderator
New Microbes New Infect
. 2020 Aug 27;100750.
doi: 10.1016/j.nmni.2020.100750. Online ahead of print.
Are two consecutive negative RT-PCRs enough to rule out COVID-19?
Rami Waked[SUP] 1 [/SUP], Jennifer Makhoul[SUP] 1 [/SUP], Gebrael Saliba[SUP] 1 [/SUP], Nabil Chehata[SUP] 1 [/SUP], Sadek Mortada[SUP] 2 [/SUP], Antoine Zoghbi[SUP] 3 [/SUP], Jacques Choucair[SUP] 1 [/SUP], Elie Haddad[SUP] 1 [/SUP]
Affiliations
Abstract
The COVID-19 pandemic is redefining the world we live in, and scientists are struggling to find an optimal SARS-CoV-2 diagnostic tool. Routine testing is currently performed using real time reverse transcription polymerase chain reaction (RT-PCR) of upper or lower respiratory tract secretions. The objective of this article is to demonstrate the importance of conducting RT-PCRs using deep sampling when initial upper respiratory testing is negative, in cases of high index of suspicion for COVID-19. We present the case of a 47-year-old man admitted for fever and bilateral pneumonia on chest CT scan, amid the early peak of the COVID-19 pandemic, suggesting a SARS-CoV-2 infection. RT-PCR results done twice using nasopharyngeal swabs were negative. A bronchoscopy was then performed, and RT-PCR testing on bronchoalveolar lavage yielded positive results, confirming the diagnosis of COVID-19 pneumonia. In conclusion, RT-PCR samples of the lower respiratory tract likely contain a higher viral load and thus retain a higher sensitivity for SARS-CoV-2 detection.
Keywords: COVID-19; Coronavirus; Pneumonia; Polymerase chain reaction; SARS-CoV-2.
. 2020 Aug 27;100750.
doi: 10.1016/j.nmni.2020.100750. Online ahead of print.
Are two consecutive negative RT-PCRs enough to rule out COVID-19?
Rami Waked[SUP] 1 [/SUP], Jennifer Makhoul[SUP] 1 [/SUP], Gebrael Saliba[SUP] 1 [/SUP], Nabil Chehata[SUP] 1 [/SUP], Sadek Mortada[SUP] 2 [/SUP], Antoine Zoghbi[SUP] 3 [/SUP], Jacques Choucair[SUP] 1 [/SUP], Elie Haddad[SUP] 1 [/SUP]
Affiliations
- PMID: 32874594
- PMCID: PMC7451052
- DOI: 10.1016/j.nmni.2020.100750
Abstract
The COVID-19 pandemic is redefining the world we live in, and scientists are struggling to find an optimal SARS-CoV-2 diagnostic tool. Routine testing is currently performed using real time reverse transcription polymerase chain reaction (RT-PCR) of upper or lower respiratory tract secretions. The objective of this article is to demonstrate the importance of conducting RT-PCRs using deep sampling when initial upper respiratory testing is negative, in cases of high index of suspicion for COVID-19. We present the case of a 47-year-old man admitted for fever and bilateral pneumonia on chest CT scan, amid the early peak of the COVID-19 pandemic, suggesting a SARS-CoV-2 infection. RT-PCR results done twice using nasopharyngeal swabs were negative. A bronchoscopy was then performed, and RT-PCR testing on bronchoalveolar lavage yielded positive results, confirming the diagnosis of COVID-19 pneumonia. In conclusion, RT-PCR samples of the lower respiratory tract likely contain a higher viral load and thus retain a higher sensitivity for SARS-CoV-2 detection.
Keywords: COVID-19; Coronavirus; Pneumonia; Polymerase chain reaction; SARS-CoV-2.