Clinical relevance of cytokines Il-6, Il-8, and C-reactive protein in the blood of patients with acute pancreatitis

Abstract

The detection of cytokines may elucidate the pathophysiological mechanisms that produce early systemic complications in acute interstitial (i) or necrotizing (n) pancreatitis (AP). The increase in the level of cytokines in the blood of patients with AP may correlate with the severity of the disease. In a prospective clinical trial from October 1992 to August 1993, 23 patients with AP were recruited and blood samples taken for cytokine detection by commercially available Elisa kits and C-reactive protein (CRP) by laser nephelometry. Six of 11 patients with nAP died either early (n = 1) or of late septic complications. None died of iAP. The peak of cytokine and CRP level in the first 3 days of hospitalization was used for calculation. The IL-6 concentration in the blood reached up to 2600 pg/ml in the 1st few days, depending on the severity of AP, and dropped to almost zero in the next days, independently of the clinical course. The differentiation of i- versus nAP, using a cut-off line of 600 pg/ml, was correct in 20 patients [87%, sensitivity (SE): 82%, specificity (SP): 91%, P < 0.001]. The blood levels of IL-8 reached a maximum of 1381 pg/ml in the 1st few days, depending on the severity of AP, and showed a correlation with the clinical course in the following days. The peak of IL-8 blood levels indicated correctly the severity of AP in 18 out of 23 patients using a cutoff level of 200 pg/ml (accuracy: 78%, SE: 82%, SP: 75%, P < 0.01). The CRP levels increased up to a maximum of 535 mg/l and indicated the course of AP correctly in 18 out of 22 patients (SE and SP 82%, P < 0.01). There was no correlation between cytokine blood levels and mortality. In the blood samples of five patients with i- or nAP, no TNF-alpha was detectable. The blood levels of IL-6, and to a lesser extent of IL-8 and CRP, can predict the severity and early systemic complications of AP. The excessive rise in cytokines can be explained by the stimulation of immunological cells (macrophages, lymphocytes and endothelial cells) in the course of AP, inducing early systemic complications.

Correlation between ranson score and red cell distribution width (RDW) in acute pancreatitis

“…[21] Variety of results (sensitivity: 72-100%, specificity: 75-81%) have been reported for prediction of infected necrosis in AP. [22,23] Despite high prediction rates, however, it still has limited use in daily clinical practice.…”

The predictive value of C-reactive protein (CRP) in acute pancreatitis – is interval change in CRP an additional indicator of severity?

“…12 In addition to clinical scoring systems, numerous individual biomarkers have been proposed as having predictive value in AP: C-reactive protein (CRP), blood urea nitrogen (BUN), haematocrit and interleukins 6 and 8. [13][14][15][16][17] CRP is one of the most commonly used biomarkers as it is routinely recorded, is relatively inexpensive and has been shown to correlate well with severity. 13,[18][19][20] Though CRP at time of admission has been shown to be a poor predictor of severity, 10 levels of >150 mg/L within the first 48 h have a high sensitivity for predicting severe disease.…”

Acute pancreatitis

“…When compared directly with CRP, TNF α , IL-1B and IL-8, IL-6 (using a cut-off >400 pg/mL at 24 h) was superior with an overall accuracy of 88%. 132 Stoelben et al 133 found that late elevation of IL-6 (>600 pg/L at 72 h) was also a useful predictor of PN with a PPV and NPV of 89% and 85%, respectively. The limitations of IL-6 are the complexity of the assay and that accuracy diminishes if measured on admission rather than at 24 h with a reported sensitivity and specificity of 70% and 79%, respectively.…”