ROLE OF PLATELET PARAMETERS IN DENGUE FEVER IN CHILDREN

Abstract

Aim: To evaluate the role of platelet parameters in dengue fever and also to determine relationship of platelet parameters with platelet count and the severity of the disease. The platelet para Materials and methods: meters [platelet count, plateletcrit, mean platelet volume (MPV), platelet distribution width (PDW)] of 50 dengue infected children were calculated using BC 3000 plus Mindray Automated Hematology Analyzer. Normal range of MPV is 7.5-11.5 . Plateletcrit cut off value in thrombocytopenia is 0.2-0.36%. The PDW reported varies with reference intervals ranging from 8.3 to 56.6%. Subjects were divided into four groups according to their platelet count on day 3 of illness (<20,000 cells/cumm, 20,000 to 50,000 cells/cumm, 50,000 to 100,000 cells/cumm and >100,000 cells/cumm). Platelet indices were studied among these groups and also the indices were evaluated with respect to the severity of disease as group A (dengue without warning signs), group B (dengue with warning signs and group C (severe dengue). Results: Male: female ratio was 28:22. Mean age of presentation was 7.8 + 2.2 years. Thirty-ve patients belonged to Group A, 26 to group B and 2 belonged to group C. PLT (cells/cumm) on Day 3 and Day 7 was 91,828 ±33,532 vs 195,371 + 70,586 in Group A patients (p<0.0001), 69,076 ±45,904 vs 163,230 + 85,053 in Group B patients (p=0.0018) 38,500 + 38,890 vs 86,000 + 28,284 in Group C patients (p=0.29). PCT (%) on Day 3 and Day 7 was 0.09 + 0.04 vs 0.18 + 0.06 in Group A patients (p<0.0001), 0.07 + 0.04 vs 0.15 + 0.07 in Group B patients (p=0.0009) and 0.04 + 0.04 vs 0.08 + 0.28 in Group C patients (p=0.84). MPV () on Day 3 and Day 7 was 10.73 + 1.07 vs 11.34 + 1.09 in Group A patients (p=0.0212), 10.41 + 1.39 vs 10.87 + 0.99 in Group B patients (p=0.3389), 9.35 + 1.62 vs 10.3±1.41 in Group C patients (p=0.59). PDW () on Day 3 and Day 7 was 14.46 ± 1.35 vs 13.22 + 1.10 in Group A patients (p=0.0001), 14.61 + 1.36 vs 13.0 + 0.76 in Group B patients (p=0.0011) and 14.5 + 1.84 vs 13.5 + 0.71 in Group C (p=0.54). Though MPV was lower in patients with platelet count <20,000 cells/cumm (8.57 + 0.5 ) as compared to other groups, it was not statistically signicant (p=0.325). PCT increases with increase in platelet count on Day 3 and Day 7 (p=0.000). Though PDW was lower on Day 3 in patients with platelet count <20,000 cells/cumm as compared to the other 3 groups, it was not statistically signicant (p=0.0740). Conclusion: Lower platelet count and low PCT are seen with severe dengue, increasing platelet count and PCT suggest recovery phase of dengue. MPV had no correlation with severity of dengue or level of thrombocytopenia suggestive that there is no role to predict severity of dengue. PDW does not uctuate with severity of dengue or level of thrombocytopenia