Altered profiles of serum amino acids in patients with sepsis and septic shock - Preliminary findings

Background: The clinical and diagnostic significance of systemic amino acids in sepsis and septic shock is unclear. Hence, the purpose of our study was to assess amino acids relationship with sepsis-related clinical data and to analyze whether they might have prognostic and discriminative value in sepsis and septic shock. Materials and methods: Prospective and observational study with 5-day follow-up. Circulating amino acids were measured in 20 patients with sepsis or septic shock diagnosis and 30 healthy volunteers by means of targeted metabolomics (LC-MS/MS). Results: Non-survivors were distinguished by significant elevated concentration of hPro (1st and 2nd day) and by mHis (5th day). Septic shock was associated with significant increased concentration of hPro (1st and 5th day) and Gly-Pro, His, Sarc and Phe (2nd day), Gly-Pro (3rd day) and Gly-Pro and mHis (5th day). In non-survivors was observed the rising trend in concentration of His (P = 0.04; 2nd day) and declining trend in concentration of Asn (P = 0.004; 5th day) and Pro (P = 0.03; 3rd day). In septic shock was observed mainly the declining trend in concentration of Arg (P = 0.03; 5th day), APA (P = 0.04; 2nd day), Lys (P = 0.02; 5th day), Sarc (P = 0.04; 5th day), Ser (P = 0.02; 5th day), Val (P = 0.04; 5th day), Trp (P = 0.03; 5th day) and Gly-Pro (P = 0.03; 2nd day; P = 0.02; 3rd day). Conclusion: Sepsis and septic shock are associated with altered concentration of serum amino acids indicative particularly of the intensified breakdown of muscle and connective tissue proteins leading to the accumulation of their characteristic degradation products. Some amino acids hold potential as predictors of sepsis progression and outcome but, in the light of discrepancies between studies, should be assessed in more numerous cohort study.