Serum Levels of Vitamin C and Thiamin in Children With Suspected Sepsis: A Prospective Observational Cohort Study.

Objectives: Vitamin C and thiamin have been trialed as adjunctive therapies in adults with septic shock but their role in critically ill children is unclear. We assessed serum levels of vitamin C and thiamin in children evaluated for sepsis.

Design: Single-center prospective observational study. Serum levels of vitamin C and thiamin were measured on admission and association with multiple organ dysfunction syndrome (MODS) was explored using logistic regression.

Setting: Emergency department and PICU in a tertiary children's hospital, Queensland, Australia.

Patients: Children greater than 1 month and less than 17 years evaluated for sepsis.

Interventions: Not applicable.

Measurements And Main Results: Vitamin levels were determined in 221 children with a median age of 3.5 (interquartile range [IQR] 1.6, 8.3) years. Vitamin C levels were inversely correlated with severity as measured by pediatric Sequential Organ Failure Assessment (Spearman's rho = -0.16, p = 0.018). Median (IQR) vitamin C levels on admission were 35.7 (17.9, 54.1) µmol/L, 36.1 (21.4, 53.7) µmol/L, and 17.9 (6.6, 43.0) µmol/L in children without organ dysfunction, single organ dysfunction, and MODS, respectively (p = 0.017). In multivariable analyses, low levels of vitamin C at the time of sampling were associated with greater odds of MODS (adjusted odds ratio [aOR] 3.04; 95% CI, 1.51-6.12), and vitamin C deficiency was associated with greater odds of MODS at 24 hours after sampling (aOR 3.38; 95% CI, 1.53-7.47). Median (IQR) thiamin levels were 162 (138, 192) nmol/L, 185 (143, 200) nmol/L, and 136 (110, 179) nmol/L in children without organ dysfunction, single organ dysfunction, and MODS, respectively (p = 0.061). We failed to identify an association between thiamin deficiency and either MODS at sampling (OR 2.52; 95% CI, 0.15-40.86) or MODS at 24 hours (OR 2.96; 95% CI, 0.18-48.18).

Conclusions: Critically ill children evaluated for sepsis frequently manifest decreased levels of vitamin C, with lower levels associated with higher severity.