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Clinical Outcome of PCR-Negative COVID-19 Patients: A Retrospective Study
Abdullah Sayıner1, Mehmet Sezai Tasbakan1, Begüm Ergan2
1Department of Chest Diseases, Ege University, İzmir, Turkey.
Insights
Approximately one-third of coronavirus disease 2019 (COVID-19) patients diagnosed clinically and radiographically tested negative for the virus via polymerase chain reaction (PCR). These PCR-negative COVID-19 patients experienced less severe illness and shorter hospital stays.
Area of Science:
- Infectious Diseases
- Clinical Medicine
- Respiratory Medicine
Background:
- Coronavirus disease 2019 (COVID-19) diagnosis relies heavily on polymerase chain reaction (PCR) testing.
- Clinical and radiographic findings are sometimes used for diagnosis in PCR-negative cases.
Purpose of the Study:
- To evaluate the clinical features and outcomes of patients diagnosed with COVID-19 but testing negative for the virus via PCR.
- To compare the characteristics and outcomes of PCR-negative COVID-19 patients with those who tested positive.
Main Methods:
- Retrospective analysis of 349 patients admitted with a COVID-19 diagnosis between March 15 and May 15, 2020.
- Comparison of clinical findings and outcomes between PCR-positive and PCR-negative patient groups.
Main Results:
- 126 (36.1%) patients were PCR-negative, presenting with higher lymphocyte counts and less frequent bilateral radiographic findings.
- PCR-negative patients were younger and exhibited less severe disease.
- Outcomes for PCR-negative patients included lower intensive care unit admission rates, reduced need for oxygen therapy and ventilatory support, and shorter hospital stays.
Conclusions:
- About one-third of COVID-19 diagnoses were PCR-negative, relying on clinical and radiographic evidence.
- PCR-negative COVID-19 patients demonstrate a more favorable clinical course and better outcomes.
- These findings highlight the importance of clinical and radiographic assessment in COVID-19 diagnosis and management.
Objective:
To evaluate the clinical features and outcomes of patients who were admitted with a diagnosis of coronavirus disease 2019 (COVID-19) but who were not confirmed with polymerase chain reaction (PCR) positivity.
Material And Methods:
This is a retrospective analysis of all patients admitted to two tertiary care centers between March 15 and May 15, 2020, with a diagnosis of COVID-19. From a common database prepared for COVID-19, we retrieved the relevant data and compared the clinical findings and outcomes of PCR-positive patients with those of PCR-negative cases who had been diagnosed on the basis of typical clinical and radiographic findings.
Results:
A total of 349 patients were included in the analysis, of which 126 (36.1%) were PCR-negative. PCR-negative patients were younger (54.6 ± 20.8 vs. 60.8 ± 18.9 years, P = .009) but were similar to PCR-positive patients in terms of demographics, comorbidities, and presenting symptoms. They had higher lymphocyte counts (1519 ± 868 vs. 1331 ± 737/mm3, P = .02) and less frequently presented with bilateral radiographic findings (68.3% vs. 79.4%, P = .046) than PCR-positive patients. Besides, they had less severe disease and better clinical outcomes regarding admission to the intensive care unit (9.6% vs. 20.6%, P = .023), oxygen therapy (21.4% vs. 43.5%, P < .001), ventilatory support (3.2% vs. 11.2%, P = .03) and length of hospital stay (5.0 ± 5.0 vs. 9.7 ± 5.9 days, P < .001).
Conclusion:
This study confirms that about one-third of the COVID-19 patients are PCR-negative and diagnosed based on clinical and radiographic findings. These patients have a more favorable clinical course, shorter hospital stays, and are less frequently admitted to the intensive care unit.
