Serum levels of interleukin‐6 may predict organ dysfunction earlier than SOFA score

• Published in: Acute medicine & surgery 2017-07, Vol.4 (3), p.255-261
• Main Authors: Shimazui, Takashi, Matsumura, Yosuke, Nakada, Taka‐aki, Oda, Shigeto
• Format: Article
• Language: English
• Subjects: critical illness; Cytokines; C‐reactive protein; interleukin‐6; Original; procalcitonin; sequential organ failure assessment scores
• ISSN: 2052-8817; 2052-8817
• DOI: 10.1002/ams2.263

Aim To investigate the clinical utility of interleukin‐6 (IL‐6), procalcitonin (PCT), and C‐reactive protein (CRP) as predictive markers in consideration of the time‐course changes in critically ill patients with organ dysfunction. Methods Serum levels of IL‐6, PCT, CRP, and Sequential Organ Failure Assessment (SOFA) scores were measured sequentially in 92 patients during their initial 5 days following admission to the intensive care unit. Maximum values were analyzed. Patients were assigned to a low ( ≤ 8), intermediate ( > 8 and ≤ 16), or high ( > 16 and ≤ 24) SOFA score group. Results There were significant differences in the maximum serum levels of IL‐6 and PCT among the three SOFA score groups (IL‐6, P < 0.0001; PCT, P = 0.0004). Specifically, comparisons between the groups revealed significant differences in IL‐6 levels (low versus intermediate, P = 0.0007; intermediate versus high, P = 0.0010). The probability of patients with the maximum value was greatest on day 1 (56.5%) for IL‐6, on day 1 (39.1%) or day 2 (38.0%) for PCT, on day 3 (39.1%) for CRP, and on day 1 (43.5%) for SOFA score. The median (interquartile range) peak day of IL‐6 was day 1 (1–2), which was significantly earlier than that of SOFA score at day 2 (1–3) (P = 0.018). Conclusion Serum levels of IL‐6 reflected the severity of organ dysfunction in critically ill patients most accurately compared to PCT and CRP. Interleukin‐6 elevated soonest from the insult and reached its peak earlier than SOFA score. IL‐6 reflected SOFA score more accurately and increased earlier than PCT or CRP. IL‐6 is useful to assess severity in the early phase of critical illness.