Rofo 2022; 194(10): 1110-1118
DOI: 10.1055/a-1779-9230
Chest

CT Findings in Patients with COVID-19-Compatible Symptoms but Initially Negative qPCR Test

CT-Manifestationen in Patienten mit COVID-19-typischen Symptomen trotz initial negativem qPCR-Test
1   University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf, Germany
,
1   University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf, Germany
,
Tobias Wienemann
2   University Dusseldorf, Medical Faculty, Institute of Medical Microbiology and Hospital Hygiene, D-40225 Dusseldorf, Germany
,
Marcel Andree
3   University Dusseldorf, Medical Faculty, Institute of Virology, D-40225 Dusseldorf, Germany
,
Verena Keitel
4   University Dusseldorf, Medical Faculty, Department of Gastroenterology, Hepatology and Infectious Diseases, D-40225 Dusseldorf, Germany
,
1   University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf, Germany
,
Elisabeth Appel
1   University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf, Germany
,
Marie-Helen Köhler
1   University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf, Germany
,
Christin Rademacher
1   University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf, Germany
,
Gerald Antoch
1   University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf, Germany
,
Joel Aissa
1   University Dusseldorf, Medical Faculty, Department of Diagnostic and Interventional Radiology, D-40225 Dusseldorf, Germany
› Author Affiliations

Abstract

Purpose To assess whether it is possible to reliably detect patients with strong suspicion of COVID-19 despite initially negative quantitative polymerase-chain-reaction (qPCR) tests by means of computed tomography (CT).

Materials and Methods 437 patients with suspected COVID-19 but initially negative qPCR and subsequent chest CT between March 13 and November 30, 2020 were included in this retrospective study. CT findings were compared to results of successive qPCR tests (minimum of 3 qPCR tests if CT suggested infection) to determine the sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of CT for diagnosing COVID-19.

Results COVID-19 was diagnosed correctly with a sensitivity of 100 % [95 % confidence interval (CI): 65–100] and a specificity of 88 % [95 % CI: 84–90]. A PPV of 12 % [95 % CI: 6–22] and an NPV of 100 % [95 % CI: 99–100] were determined.

Conclusion CT is able to detect COVID-19 before qPCR in initially negative patients in this special study setting. Similar CT findings in COVID-19 and other atypical pneumonias can lead to high numbers of false-positive patients, reducing the specificity of CT.

Key Points:

  • Low-dose chest CT is able to diagnose COVID-19 in symptomatic patients even in cases of an initially negative quantitative PCR result and therefore is a fast support method to detect COVID-19, especially in early disease.

  • Low-dose chest CT can reliably exclude COVID-19 in a pandemic setting.

  • CT does not always ensure a reliable differentiation from other viral diseases.

Citation Format

  • Valentin B, Steuwe A, Wienemann T, et al. CT Findings in Patients with COVID-19-Compatible Symptoms but Initially Negative qPCR Test. Fortschr Röntgenstr 2022; 194: 1110 – 1118

Zusammenfassung

Ziel Mittels dieser Studie soll evaluiert werden, ob Patienten mit starkem Verdacht auf eine SARS-CoV-2 Infektion trotz eines bereits erfolgten negativen quantitativen Polymerase-Kettenreaktion (qPCR)-Tests mittels Computertomografie (CT) verlässlich diagnostiziert werden können.

Material und Methoden In dieser retrospektiven Studie wurden 437 Patienten mit Verdacht auf COVID-19, aber initial negativer qPCR und anschließend durchgeführter Thorax-CT zwischen dem 13. März und 30. November 2020 eingeschlossen. Der Referenzstandard zu den CT-Befunden war die qPCR (mindestens 3 aufeinander folgende qPCR-Tests, im Falle eines Infektionsverdachtes durch die CT), um die Sensitivität, Spezifität, den positiven prädiktiven Wert (PPV) und den negativen prädiktiven Wert (NPV) des CT zu bestimmen.

Ergebnisse Die CT erzielte eine Sensitivität von 100 % (95 % Konfidenzintervall [KI]: 65–100), eine Spezifität von 88 % (95 % KI: 84–90), einen PPV von 12 % (95 % KI:6–22), einen NPV von 100 % (95 % KI: 99–100) und eine diagnostische Genauigkeit von 88 % (95 % KI: 84–91).

Schlussfolgerung In diesem speziellen Studiensetting kann die CT trotz initial negativer qPCR eine SARS-CoV-2 Infektion detektieren. Alle Patienten mit einem positiven CT-Befund zeigten einen fortgeschrittenen pulmonalen Befall trotz aktueller negativer qPCR. Die CT kann als diagnostische Methode bei weiterbestehendem klinischen Verdacht auf eine SARS-CoV-2 Infektion trotz negativem qPCR-Test eingesetzt werden und eine Infektion sicher ausschließen.

Kernaussagen:

  • Die Low-Dose-Thorax-CT kann infizierte Patienten trotz vorliegendem negativen qPCR-Test erkennen und eignet sich aus diesem Grund, besonders im frühen Krankheitsstadium, als additive diagnostische Methode.

  • Die Low-Dose-Thorax-CT kann eine SARS-CoV-2 Infektion in einer Pandemie verlässlich ausschließen.

  • Eine zuverlässige Differenzierung zu anderen viralen Parenchymveränderungen ist schwierig.



Publication History

Received: 08 June 2021

Accepted: 13 February 2022

Article published online:
11 May 2022

© 2022. Thieme. All rights reserved.

Georg Thieme Verlag KG
Rüdigerstraße 14, 70469 Stuttgart, Germany

 
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