Influence of COVID-19 on lymphocyte and platelet parameters among patients admitted to intensive care unit and emergency.

Objective: The aim of the study was to detect the effect of COVID-19 on lymphocyte and platelet parameters among Sudanese patients admitted to Intensive Care unit (ICU) and emergency (ER).

Patients And Methods: This cross-sectional study was carried out on a total of 787 Sudanese individuals (487 confirmed COVID-19 cases and 300 apparently healthy individuals as controls, in duration between April 2020 to December 2020). Platelets (PLTs) and platelet indices, mean platelet volume (MPV), platelet distribution width (PDW), plateletcrit (PCT) and platelet larger cell ratio (PLCR) were investigated as part of the complete blood count (CBC) for the case and control group. Also, the neutrophil lymphocyte ratio (NLR) and platelet lymphocyte ratio (PLR) were calculated, and the results were statistically analyzed by SPSS version 21.

Results: The severity of the disease was also affected by the patient's age: 262 COVID-19 cases admitted to ICU were over 50 years old, compared to only four patients in the mild group. Regarding hematological parameters, the absolute lymphocyte count, PLTs, MPV, PDW, and P-LCR were significantly different between cases and control groups (p-values = 0.000, 0.002, 0.000, 0.000, and 0.000, respectively). PLR and NLR levels were found to be significantly higher as disease severity increased; p-values = 0.000 and 0.000, respectively. The study also demonstrated that lymphopenia was associated with severe COVID-19 infection (in 93% of ICU patients, 59.9% of ER, and 9% of the mild group), while thrombocytopenia was detected only among 30.8% of ICU patients.

Conclusions: Lymphopenia and thrombocytopenia are associated with severe COVID-19 infection. NLR and PLR were markedly increased with COVID-19.