Reliability of Haematological Parameters and Ratios Obtained from Automated Haematology Analysers in Predicting the Clinical Condition of the Patient - A Study from a Tertiary Care Hospital in New Delhi

Abstract

BACKGROUND Modern automated analysers provide various haematological parameters which have gained a lot of clinical significance. Of these, platelet indices are the most recent one which need to be explored in various diseases. The present study was conducted to evaluate the significance of platelet indices, neutrophil-tolymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), and mean platelet volume–to-platelet count in critically ill patients. METHODS This is a prospective study carried out in emergency laboratory of pathology department. 100 patients of intensive care units (ICU) and non-intensive care units (Non-ICU) visiting to the emergency department were included in the study. Fortyfive age and sex matched control patients were taken. The ethylenediamine tetra acetic acid (EDTA) blood sample was analysed on automated analyser. Platelet indices, NLR, MLR and mean platelet volume to platelet counts were calculated in ICU, Non-ICU and control groups. All these values were compared among these groups. RESULTS The study included 400 patients (200 critically ill and 200 non-critically ill) and 45 healthy controls from normal population. The male to female ratio in critically ill and non-critically ill patients was 1.3 : 1 (113 : 87) and 1.08 : 1 (104 : 96) respectively. The critically ill patients had significant leucocytosis (P = 0.019) with neutrophilia (P = 0.005) and lymphopenia (P = 0.048) when compared to noncritically ill patients. There was a significant difference of NLR (P = 0.010), MLR (P = 0.027) and MPV : Platelet count (P = 0.045) in these two groups. However, platelet count and platelet indices were not showing any significant difference in these groups. CONCLUSIONS In the era of modern auto analysers, we should try to utilize the maximum information that could be provided by these machines in forms of various indices and ratios. The present study highlights that neutrophilic leucocytosis with lymphopenia is seen in critically ill patients when compared to non-critically ill patients and normal control population. NLR, MLR and MPV to platelet ratios are also of great importance whereas platelet count and platelet indices are always not helpful in categorization of severity of the patient’s condition. KEYWORDS Intensive Care Unit Patients, Neutrophil Lymphocyte Ratio, Monocyte Lymphocyte Ratio, Mean Platelet Volume