Mean platelet volume and uric acid levels in neonatal sepsis.

Objectives: To determine the role of mean platelet volume (MPV) and uric acid levels in the diagnosis of neonatal sepsis (NS).

Methods: A total of 146 newborns with suspected NS were prospectively included in the study and infants without NS (n = 142) were assigned as controls. The patients were divided into three groups: Group I (n = 64): clinical NS, Group II (n = 82): culture-proven NS, and Group III (n = 142): healthy controls.

Results: The patients in Group II had the highest C-reactive protein (CRP) levels (54.6 ± 5.4 mg/L), lowest platelet counts (199,329 ± 135,952/mm(3)) and lowest uric acid levels (2.6 ± 1.8 mg/dL) when compared to Groups I and III (p < 0.05, for all comparisons). MPV values were higher in Group I (10.6 ± 1.1 fL) and Group II (10.4 ± 0.9 fL) when compared to Group III (9.2 ± 1.2 fL) (p = 0.001), although there was no difference between Groups I and II. Area under curve (AUC) values for CRP, MPV, and uric acid were 0.92 (p = 0.001), 0.76 (p = 0.001) and 0.28 (p = 0.001), respectively. The diagnostic cut-off values for CRP and MPV were 9.5 mg/dL and 10.4 fL. Sensitivity and specificity of MPV in NS were 54 % and 82 % respectively. When combined with CRP its sensitivity and specificity increased to 89 % and 79 % respectively.

Conclusions: The combined use of CRP and MPV should be considered in the early diagnosis of NS, but uric acid levels may only be utilized as an additional tool to support diagnosis. CRP is shown to be more sensitive and specific than MPV and uric acid in diagnosing neonatal sepsis.