eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2026-05-13 19 2 71824 article Mohammed Hasan Mukhtar 1 Wesam Ahmed Nasif 1 Abdullatif Taha Babakr 1 Sameer Hasan Fatani 1 Mohammad Althubiti 1 Soud Abdulraof Khogeer 1 Department of Biochemistry, Faculty of Medicine, Umm Al-Qura University, Makkah, K.S.A Faculty of Medicine, Ain-Shams University, Egypt Molecular Biology Department, Genetic Engineering and Biotechnology Research Institute, Sadat City University, Sadat City, Egypt. The search for reliable biomarkers to predict the severity and outcomes of COVID-19 remains critical. Aim: to evaluate the diagnostic and prognostic value of LDH in patients with COVID-19. A retrospective cohort study was conducted on 2184 confirmed COVID-19 patients from hospitals in Makkah, Saudi Arabia. Demographic, clinical, and laboratory data, including LDH levels, were collected.  Statistical analyses were performed using SPSS. The overall recovery rate was 96.4%, with a 3.6% mortality rate.  Mean LDH levels were significantly higher in severe cases (399.8 ± 80.60 U/L) compared to non-severe cases (272.9 ± 72.4 U/L) and in deceased patients (488 ± 77 U/L) compared to survivors (250 ± 45 U/L) (p < 0.001). LDH levels were also significantly elevated in COVID-19 patients versus controls. ROC curve analysis demonstrated that LDH could discriminate between COVID-19 patients. Furthermore, LDH showed significant positive correlations with CRP, D-dimer, and ferritin. So Elevated LDH is strongly associated with COVID-19 severity and mortality. https://biomedpharmajournal.org/vol19no2/longitudinal-trends-in-lactate-dehydrogenase-levels-and-covid-19-outcomes/ COVID-19 Disease Severity Lactate Dehydrogenase (LDH) Prognostic Biomarker Risk Stratification