Immature platelet fraction as predictive index of sepsis

Introduction

The incidence of sepsis is reported around 37% in European ICUs [1]. The mortality rate depends on the severity of organ failure, up to 65% if four or more organs are involved. Multiple organ failure (MOF) is due to microcirculatory dysfunction with microthrombosis resulting from coagulation disorders including platelets' activation. An early diagnosis should identify the microcirculatory dysfunction before MOF became clinically evident. The diagnosis of sepsis is commonly based on clinical criteria, pathogen identification and use of markers like procalcitonin (PCT) and C-reactive protein (PCR) associated with infection. The aim of our study is to evaluate whether the routine measurement of immature platelet fraction (IPF), considered a precocious marker of platelet production, is associated with sepsis and its severity and/or whether it could be used as a predicting marker of sepsis.

Methods

We enrolled 66 consecutive patients admitted to the ICU, dividing them into two groups: septic (n = 44) and no septic (n = 22). The severity of sepsis was evaluated. The exclusion criterion was a platelet count <150,000/mm3. Blood count, coagulation, PCR, PCT, and IPF were collected every day.

Results

The IPF values between septic (4.6 ± 3.1) and no septic patients (3.3 ± 1.5) did not differ (P = 0.16). No correlation was found between IPF values and the severity of septic condition (no sepsis 11.7 ± 10.1; sepsis 14.3 ± 10.5; severe sepsis 10.5 ± 9.1; septic shock 19.5 ± 12.4; P = 0.3). When we considered only subjects who did not have sepsis at the ICU admission we found that patients who developed sepsis during the recovery had IPF values higher than patients who did not develop sepsis (Table 1).

Table 1

Conclusions

From our results IPF cannot be considered a marker of sepsis. Conversely it could be used as predictive index of sepsis because it can identify patients who will develop sepsis.