The Use of Predictive Laboratory Tests in Rapid Triage of COVID-19 Pandemic Outpatient Clinic Patients.

Abstract

Patients who come to the emergency pandemic outpatient clinic with a pre-diagnosis of COVID-19 are still a burden on the health system. Rapid triage of patients is important to reduce transmission. The aim of this study is to evaluate the biochemistry and hemogram results of real-time reverse transcription-polymerase chain reaction (RT-PCR) positive and negative patients in the emergency pandemic outpatient clinic and to investigate predictive values of the initial tests that will help to make rapid diagnosis. Patients who applied to the emergency pandemic outpatient clinic with the suspicion of COVID-19 between November 01, 2020 and January 01, 2021 were evaluated with RT-PCR and laboratory examinations. A total of 551 patients were included in the study. The mean age of the patients was 50.31 ± 18.47 (min. 18 - max. 94), and 47.2% (n = 260) of the patients included in the study were male and 52.8% (n = 291) were female. In the comparison of hemogram parameters, we found that mean platelet volume (MPV) was significantly higher (p = 0.023), whereas white blood cell (WBC), platelet counts (PLT), lymphocyte and neutrophil values were significantly lower in RT-PCR positive patients (p < 0.001). There were no significant differences between the PCR positive and negative patients in terms of other parameters. In the comparison of biochemical parameters, we found that lactate dehydrogenase LDH (p = 0.001), creatinine (p = 0.002), and AST (p < 0.001) values were significantly higher in PCR positive patients, while there were no significant differences in terms of other biochemical parameters (p > 0.05). Our study results show that the practical quick-look hemogram and MPV can be used as a specially evaluated parameter in the rapid management of the first application COVID-19 patients. In addition, biochemically high levels of LDH and creatinine can be used to guide the clinician in terms of early hydration of the patient with a pre-diagnosis of COVID-19 to alleviate acute kidney damage.