Mean Platelet Volume (MPV), Platelet Distribution Width (PDW), Platelet  Count and Plateletcrit (PCT) as predictors of in-hospital paediatric mortality:  a case-control Study.

Zainab Mohammedi Golwala, Hardik Shah, Neeraj Gupta, V. Sreenivas, Jacob. M. Puliyel
1. Department of Pediatrics and Neonatology, St. Stephens Hospital, New Delhi.
2. Department of Biostatistics, All India Institute of Medical Sciences, New Delhi.

Abstract
Background: Thrombocytopenia has been shown to predict mortality. We hypothesize that platelet indices may be more useful prognostic indicators. Our study subjects were children one month to 14 years old admitted to our hospital.

Aim: To determine whether platelet count, plateletcrit (PCT), mean platelet volume (MPV) and platelet distribution width  (PDW) and their ratios can predict mortality in hospitalised children.

Methods: Children who died during hospital stay were the cases. Controls were age matched children admitted contemporaneously. The first blood sample after admission was used for analysis. Receiver operating characteristic (ROC) curve was used  to identify the best threshold for measured variables and the ratios studied. Multiple regression analysis was done to identify  independent predictors of mortality.

Results: Forty cases and forty controls were studied. Platelet count, PCT and the ratios of MPV/Platelet count, MPV/PCT,  PDW/Platelet count, PDW/PCT and MPV x PDW/Platelet count x PCT were significantly different among children who  survived compared to those who died. On multiple regression analysis the ratio of MPV/PCT, PDW/Platelet count and MPV/ Platelet count were risk factors for mortality with an odds ratio of 4.31(95% CI, 1.69-10.99), 3.86 (95% CI, 1.53-9.75), 3.45 (95% , 1.38-8.64) respectively. In 67% of the patients who died MPV/PCT ratio was above 41.8 and PDW/Platelet count was above  3.86. In 65% of patients who died MPV/Platelet count was above 3.45.

Conclusion:The MPV/PCT, PDW/Platelet count and MPV/Platelet count, in the first sample after admission in this case  control study were predictors of mortality and could predict 65% to 67% of deaths accurately.

Keywords:SICK Score, PRISM, severity of illness scores PIM, in-hospital mortality; platelet indices.