Clinical characteristics of hospitalized patients with false-negative severe acute respiratory coronavirus virus 2 (SARS-CoV-2) test results

MacKenzie, Erica L.; Hareza, Dariusz A.; Collison, Maggie W.; Czapar, Anna E.; Kraft, Antigone K.; Waxse, Bennett J.; Friedman, Eleanor E.; Ridgway, Jessica P.

OBJECTIVE: To determine clinical characteristics associated with false-negative severe acute respiratory coronavirus virus 2 (SARS-CoV-2) test results to help inform coronavirus disease 2019 (COVID-19) testing practices in the inpatient setting. DESIGN: A retrospective observational cohort study. SETTING: Tertiary-care facility. PATIENTS: All patients 2 years of age and older tested for SARS-CoV-2 between March 14, 2020, and April 30, 2020, who had at least 2 SARS-CoV-2 reverse-transcriptase polymerase chain reaction tests within 7 days. METHODS: The primary outcome measure was a false-negative testing episode, which we defined as an initial negative test followed by a positive test within the subsequent 7 days. Data collected included symptoms, demographics, comorbidities, vital signs, labs, and imaging studies. Logistic regression was used to model associations between clinical variables and false-negative SARS-CoV-2 test results. RESULTS: Of the 1,009 SARS-CoV-2 test results included in the analysis, 4.0% were false-negative results. In multivariable regression analysis, compared with true-negative test results, false-negative test results were associated with anosmia or ageusia (adjusted odds ratio [aOR], 8.4; 95% confidence interval [CI], 1.4–50.5; P = .02), having had a COVID-19–positive contact (aOR, 10.5; 95% CI, 4.3–25.4; P < .0001), and having an elevated lactate dehydrogenase level (aOR, 3.3; 95% CI, 1.2–9.3; P = .03). Demographics, symptom duration, other laboratory values, and abnormal chest imaging were not significantly associated with false-negative test results in our multivariable analysis. CONCLUSIONS: Clinical features can help predict which patients are more likely to have false-negative SARS-CoV-2 test results.