DIAGNOSTIC PERFORMANCE OF SERUM C-REACTIVE PROTEIN, ASPARTATE AMINOTRANSFERASE, ALANINE AMINOTRANSFERASE, AND LACTATE DEHYDROGENASE AS ADJUNCTS TO RT-PCR IN DETECTION OF COVID-19
DOI:
https://doi.org/10.69656/pjp.v22i3.1873Keywords:
COVID-19, CRP, LDH, RT-PCR, Sensitivity, SpecificityAbstract
Background: COVID-19 is a highly transmissible viral infection caused by SARS-CoV-2, with clinical manifestations ranging from asymptomatic disease to severe pneumonia and multi-organ involvement, necessitating timely and accurate diagnosis. Aim was to determine the diagnostic accuracy of serum C-reactive protein (CRP), Aspartate Aminotransferase (AST), Alanine aminotransferase (ALT), and Lactate dehydrogenase (LDH) levels as detecting COVID-19, using RT-PCR as gold standard. Methods: This Cross-sectional study was conducted in Department of Pathology, Bahawal Victoria Hospital/Civil Hospital Bahawalpur, from 10th Jan to 9th Jul 2023. After informed consent nasopharyngeal swab for RT-PCR and blood samples for CRP, AST, ALT, and LDH were collected from 165 symptomatic patients suspected of COVID-19. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and diagnostic accuracy were calculated. Results: Sensitivity, specificity, PPV, NPV, and diagnostic accuracy of serum CRP in Detecting COVID-19 taking RT-PCR as a gold standard were 83.87, 69.44, 78.0, 76.92 and 77.58% respectively. Sensitivity, specificity, PPV, NPV and diagnostic accuracy of serum AST levels were 80.65, 68.06, 76.53, 73.13 and 75.15% respectively. Sensitivity, specificity, PPV, NPV and diagnostic accuracy of the serum ALT were 81.72, 68.06, 76.77, 74.24 and 75.76% respectively. Sensitivity, specificity, PPV, NPV and diagnostic accuracy of the serum LDH were 86.02, 72.22, 80.0, 80.0 and 80.0% respectively. Conclusion: CRP and LDH demonstrated relatively higher diagnostic performance than AST and ALT, therefore these serum markers may be used as an adjunct diagnostic tool in detecting COVID-19 in settings where RT-PCR is not available.
Pak J Physiol 2026;22(3):157–60, DOI: https://doi.org/10.69656/pjp.v22i3.1873
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