PB2273: ANALYSIS OF THE HAEMATOLOGICAL PARAMETERS AND BLOOD PICTURE FINDINGS AND THEIR IMPACT ON THE DURATION OF STAY IN A COHORT OF PATIENTS WITH COVID 19 INFECTION IN A TERTIARY CARE HOSPITAL IN SRI LANKA

Background: COVID-19 an infectious disease caused by the SARS-CoV-2 virus reveal a multi-systemic involvement, including the hemopoietic system. The haematological manifestations include blood count anomalies notably lymphopenia and neutrophilia which are of prognostic significance. Common viral infections often cause a leucopenia and frequently, thrombocytopenia. Bacterial infections are typically associated with a neutrophil leukocytosis, and raised CRP. Studies on morphological changes in peripheral blood smears in COVID-19 and their impact on clinical severity are limited. FBC and a peripheral blood smear are inexpensive, easily performed, rapid tests which could add some novelty as effective markers of disease progress. Aims: To analyze the full blood count (FBC) parameters and blood picture findings in patients with Covid 19 infection and identify the association of these parameters with the hospital stay of these patients. Methods: A retrospective analytical study done during a period January 2021 – January 2022 at the haematology department of Sri Jayewardenepura General hospital. 154 Covid PCR positive patients were randomly selected and their data in relation to age, sex, FBC parameters, CRP, D dimers, blood picture findings and days of hospitalization were obtained from the hospital records and entered into a data extraction sheet and statistically analyzed using SPSS version 20 and Pearson’s Correlation with a P value of <0.05 considered statistically significant. Ethical clearance was Obtained from the hospital ethical committee Results: The patients were in the age range of 15 to 95 years with a male preponderance of 2:1. The WBC count ranged from 2500/cu mm to 36,000/cu mm and counts < 4,000/cu mm were 12.3%. WBC counts were normal in 63.6% and high in 24%. Neutrophils were predominant but normal in 48.1% and 33.1% had neutrophilia. 96.8% revealed a lymphocyte count of <3,500/cu mm of which 52.6% had counts <1,500/cu mm. Thrombocytopenia was seen in only 38.3%. CRP was in the range of 10 -200 mg/L in 72% of patients. 53.8% revealed D dimer values ranging from100-5000 ng/ml with 13.6% having values greater than 5000ng/ml. 31.2% had no D dimer values. The blood pictures revealed a moderate rouleaux formation in 65.6%, toxic neutrophils in 85%, myelocytes in 37% and reactive lymphocytes in 55.8%. In 68.8%, comment was a bacterial infection and viral infection in 5.2%. Regards to hospital stay 3 and 5 days was of the highest frequency (25% each). A positive correlation noted between the duration of stay and age of patient (P value 0.05) with a negative correlation between the stay and lymphocyte count (P value -0.024). A positive correlation observed between WBC count and neutrophils (P value 0.00), with both demonstrating a positive correlation with platelets, CRP and D dimer, having P values of, 0.00,0.00 and 0.012/0.010 respectively with a negative correlation between WBC and lymphocytes (P value -0.025). Summary/Conclusion: Our study revealed, the FBC, blood picture and other parameters in COVID 19 depict a bacterial infection with predominance of neutrophils, lymphopenia, high CRP and normal to high platelet counts. The negative correlation between hospital stay and lymphopenia was significant, which could be considered a poor prognostic marker.