C-reactive protein for differential diagnosis of sepsis and systemic inflammatory response syndrome

I. M. Yachnyk


C-reactive protein (CRP) is an acute-phase protein found in the blood, which is synthesized by the liver in response to systemic inflammatory response syndrome (SIRS) of infectious or non-infectious genesis, mainly due to the influence of interleukin-6. The role of this protein is to facilitate the removal of microorganisms and necrotic tissue by activating cell-mediated cytotoxic cascades. It causes the intense interest in CRP as a marker of sepsis and its complications.

The objective of the research was early diagnosis of septic complications in children on the basis of clinical and laboratory tests including CRP as a marker for differential diagnosis of SIRS and sepsis, as well as its severe course.

Materials and methods. In the article the possibility of using CRP for early diagnosis of septic complications of surgical and somatic profiles in 146 children (92 patients with sepsis, 54 patients with SIRS) being hospitalized in serious condition in an intensive care unit was investigated. To determine serum CRP levels quantitative method was used.

Results. The CRP level significantly increased in patients with sepsis by 46.89 ±1.5 mg/l compared to 31.08 ±2.1 mg/l in patients with SIRS (p<0.05). Elevated CRP level was typical for patients with sepsis with a sensitivity of 78.7% and specificity of 57.4%. An increase in the “diagnostic level” of CRP by 45 mg/l (46.9 mg/l) allowed us to increase the specificity of biochemical diagnosis of sepsis by 66.4% due to decreased sensitivity. When the CRP level was 58 mg/l (58.3 mg/l) severe sepsis with a sensitivity of 42.3% and specificity of 57.6% could be stated. Even in the absence of other signs of dysfunction of organs and systems in patients with sepsis serum CRP level of 50 mg/l (51 mg/l) with a sensitivity of 41.3% and specificity of 58.6% allows us to predict the development of severe sepsis in the future.

Conclusions. Thus, increased concentration of CRP is a biochemical marker of SIRS in general and sepsis in particular.


C-reactive protein; diagnostic marker; sepsis; systemic inflammatory response syndrom; multiple organ failure

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Copyright (c) 2017 I. M. Yachnyk

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