Association of Inflammatory Markers with Mortality in COVID-19 Infection

To evaluate the association of serum ferritin, lactate dehydrogenase, and C-reactive protein at admission with in-hospital mortality in COVID-19 infection; and to determine best predictive cut-offs.

Cross-sectional study.

Department of Medicine, Combined Military Hospital, Peshawar Cantt; Pakistan from March to June 2020.

Admitted patients with SARS-CoV-2 detectable by polymerase chain reaction (PCR) were included. Patients with suggestive radiological findings but negative PCR for SARS-CoV-2, those with incomplete data or those leaving against medical advice were excluded. Serum C-reactive protein, ferritin and LDH levels were tested on admission. SARS-CoV-2 viral load was checked on nasopharyngeal samples. Disease severity was assessed using World Health Organization guidelines.

There were 238 patients, aged 41.18 ± 16.74 years. Disease was mild in 157 (65.97%), moderate in 36 (15.13%), and severe in 45 (18.91%) cases. Twenty-two (9.24%) patients died in the hospital. Serum C-reactive protein, ferritin and lactate dehydrogenase levels were elevated in 122 (51.26%), 83 (34.87%) and 184 (77.31%) patients, respectively; more frequently amongst patients with moderate/severe disease or mortality. Areas under receiver operating characteristic curves  and 95% confidence intervals for serum C-reactive protein, ferritin and LDH were 0.909 (0.854-0.964), 0.915 (0.835-0.995) and 0.863 (0.785-0.942), respectively. C-reactive protein ≥45.5 mg/L had sensitivity 86.36% and specificity 88.89%; serum ferritin ≥723 ng/ml had sensitivity 95.45% and specificity 86.57%, and lactate dehydrogenase ≥428.5 U/L had sensitivity 90.91% and specificity 80.56% for predicting mortality.

Levels of the three inflammatory markers at admission can predict mortality in COVID-19 infection. Key Words: Coronavirus, Inflammation, Mortality, Outcome, Pakistan.