Evaluation of predictive value of total leukocyte count in acute serious bacterial infections in children 1 month to 5 years

Abstract

Background: Fever in a young child is a frequently encountered clinical problem with various causes. Most of them run a benign self-limiting course that requires only symptomatic treatment. However, in a few children the underlying etiology can be a life threatening serious bacterial infection (SBI). Early identification of SBI is warranted because of the need to start antibiotic therapy, often empirical, as soon as possible to prevent morbid sequela. Total leukocyte count (TLC) is with neutrophil predominance is considered to be a surrogate marker of a bacterial infection and facilitating decision - making regarding further evaluation and empiric antibiotic therapy. The purpose of this study was to determine the utility of leukocyte in predicting SBI in a young febrile child and to correlate the leukocyte count with non-serious infection.Methods: One fifty children, age of 1 month to 60 months with fever > 38°c are included and were analyzed for demographic details, presenting symptoms, physical examination findings, clinical diagnosis, total leukocyte count, peripheral smear study, blood culture, stool culture, CSF analysis, x-ray chest, abdominal ultrasound, CT-brain. Results: Out of 150 children included in the study, the mean age was 26.7±14.54 months and the average duration of fever was 4.3±1.02 days. The mean leukocyte count was 15016.43±5801.98 cells/cu.mm. 74 children had proven serious bacterial infection (49.3%) and were categorized in Group I and remaining non-serious infection were 50.66% are belonged to Group 2. Urinary tract infection and pneumonia were the most common SBI encountered (31/20/68.91%). The highest TLC counts were seen in children with UTI. Analysis of variance (ANNOVA) did not reveal significant differences in TLC between children with different diagnosis. In Group 2, majority of the etiology was lower respiratory tract infection/inflammation and short febrile illness.Conclusions: SBI comprise only half of the febrile children with leukocytosis. The predictive accuracy of leukocytosis in diagnosing SBI is poor. Vomiting and seizures probably incite stress mediated leukocytosis and are commonly encountered in febrile child with a high TLC without SBI. Further models with addition of clinical data and other surrogates of infection need to be developed to improve prediction of SBI in a febrile child.