Dynamic lymphocyte-CRP ratio as a predictor: a single-centre retrospective study on disease severity and progression in adult COVID-19 patients.

OBJECTIVE: To assess the efficacy of dynamic changes in lymphocyte-C-reactive protein ratio (LCR) on differentiating disease severity and predicting disease progression in adult patients with Coronavirus disease 2019 (COVID-19).

METHODS: This single-centre retrospective study enrolled adult COVID-19 patients categorized into moderate, severe and critical groups according to the Diagnosis and Treatment of New Coronavirus Pneumonia (ninth edition). Demographic and clinical data were collected. LCR and sequential organ failure assessment (SOFA) score were calculated. Lymphocyte count and C-reactive protein (CRP) levels were monitored on up to four occasions. Disease severity was determined concurrently with each LCR measurement.

RESULTS: This study included 145 patients assigned to moderate ( n  = 105), severe ( n  = 33) and critical groups ( n  = 7). On admission, significant differences were observed among different disease severity groups including age, comorbidities, neutrophil proportion, lymphocyte count and proportion, D-Dimer, albumin, total bilirubin, direct bilirubin, indirect bilirubin, CRP and SOFA score. Dynamic changes in LCR showed significant differences across different disease severity groups at different times, which were significantly inversely correlated with disease severity of COVID-19, with correlation coefficients of -0.564, -0.548, -0.550 and -0.429 at four different times.

CONCLUSION: Dynamic changes in LCR can effectively differentiate disease severity and predict disease progression in adult COVID-19 patients.