P38 – Study of complement system in erysipelas patients

Author(s):
Oleg Chernyshev, Alexander Petrov, Michail Shatil, Vladislav Kotlov, Natalia Serebrynaya, Natalia Bubnova, city Hospital of Saint-George

Background: Erysipelas is an inflammatory disorder that can be complicated with SIRS and sepsis. The latter may be explained by the hyperactivation of the complement system. The complement system in erysipelas patients hasn’t been explored thoroughly. Previously a reduction of the general hemolytic activity of different complement components was reported.

Hypothesis: The activation of complement correlates with clinical features and course of erysipelas.

Methods: Plasma samples from 38 patients with different clinical erysipelas forms (26 – primary erysipelas, 12 – recurrent erysipelas) were taken on Day 1 and on Days 7-10.
The components studied were: C1-inhibitor (C1-INH) (mcg/ml), C4 (mg/ml), C3 (mg/ml), C5 (mcg/ml), anafilatoxins C3a (ng/ml) and C5a (ng/ml) and a hydrolysed form of the C3 component C3[H20] (mg/ml and % of total C3).

Results: There were significantly increased concentrations of C3a and C5a, C1-INH and C3[H20] in patients compared to healthy individuals. Correlations were found between serum concentrations of C4 and C3 (r=0,89; p<0,01) and C3a and C5a (r=0,55; p<0,01). Significant differences were found in different clinical erysipelas forms: patients with primary erysipelas (erythematous form) had significantly higher concentrations of C3a than patients with more severe bullous-hemorrhagic form (p=0,02). The portion of C3[H20] was significantly lower in patients with recurrent erysipelas (erythematous form) than in combined group of erythematous-hemorrhagic and bullous- hemorrhagic erysipelas forms (p=0,04). After treatment period we observed significantly decreased percentage of C3[H20] in patients with primary erysipelas (p=0,02) and in patients with recurrent erysipelas (p=0,02).

Conclusions: The complement system is significantly activated in erysipelas patients due to increased concentrations of the C3a (~ 3-5 times), C5a (~ 1,5 times), C1-INH (~ 1,5 times) and % C3[H20] (~ 100 times) compared to healthy individuals. Higher C3a levels are observed in patients with milder clinical forms of primary erysipelas. In recurrent erysipelas spontaneous complement activation via alternative pathway is less frequent in patients with mild forms of the disease. C3 hydrolysis is decreased during treatment in severe forms of erysipelas. We suggest that further investigation of the complement activity may allow to improve the estimation of inflammation severity, predict development of SIRS and effectiveness on therapy of erysipelas.