Leukocytosis in the Emergency Room -a Brief Overview !

Introduction : Leukocytosis in the absence of infection is a fragmentarily studied topic . Despite that it is widely considered as a marker of infection and inammation, the differential diagnosis of raised WBC count per se is an overlooked issue . (2,)Leukocytosis ( elevation of WBC count > 11×109/L ) is a common entity seen in patients presenting to emergency department . Its well described to be associated with many infectious conditions like pneumonia, soft tissue infections, urosepsis. It can also occur in wide variety of other conditions like myocardial infarction, acute pulmonary embolism, physiological stress, trauma, medications, poisoning, surgical stress, haematological malignancy.(1,6) Very few studies have described the association of leukocytosis with mortality and quiet a small number of them have been enumerated as the specic cause of this condition in the absence of overt infection. (6,7)The present study is undertaken to investigate the relationship between leukocytosis and all cause mortality and elucidate the different conditions associated with raised leukocyte counts and to nd the association between leukocytosis and mortality in a variety of conditions in the absence of overt infection. Methods : The present study is a prospective observational study. All the patients presenting to emergency department fullling the inclusion criteria , with q SOFA > 2 were included in the study . Patient details , history, total leukocyte counts and differential counts of patients were noted on day 1, day 2 and subsequently , detailed study of complete medical records of each patient , all conditions that cause fever and leukocytosis, trends of rise in WBC counts, laboratory tests, imaging studies, progress notes, diagnosis of primary care team, opinion of consultants was noted . TLC counts were noted on presentation (day 1, day 2 and day 5 ) ,presence or absence of sepsis and mortality was followed up , delta gap difference between leukocyte counts on day2 and day5) was calculated . Stratication and grouping of patients according to the level of rise in the WBC counts and as per the probable etiology of leukocytosis Separation of patients into survival and non survival groups ,presence or absence of sepsis and as per the other categories was done . Comparison between different groups of patients to nd the strength and validity of these conditions was done by using parametric and non parametric tests for continuous variables , univariate and multivariate logistic regression models were applied to assess the various conditions associated with leukocytosis. Results: The study results suggest that out of the total 818 patients recruited in the study after excluding 21 patients due to inadequate data , of the total study subjects (n =771 ) , survival group constituted 754 (92.1) % and non survival group 17(2.2)% of patients, and the mean leukocyte count in the survival group is 18123±9920 . Among the various causes of elevated leukocyte count sepsis was documented in 243 patients (31.5%). Of these 243 patients majority of them had pneumonia and urinary tract infection . Mean leukocyte counts of day 1 and day 5 did not show positive correlation with mortality (r value -0.003 and 0.018 respectively ) , however as per logistic regression analysis , delta gap (difference in leukocyte counts of day 2 and day 5) predicted the probability of death in the group as a whole. Conclusion : This study states that although the trends of rise in the leukocyte count had a positive association with mortality in few individual subgroups like sepsis , leukocytosis as such is a marker of pathological condition or serious infection only in extreme elevations with WBC count > 25000 only. Leukocytosis in the ER room as such does not show a positive association with mortality in the study group as a whole.