Endometriosis (EM) is a gynecological disorder that presents significant immune dysregulation in its pathophysiology. Recent studies indicate that the Complement System may play a significant role in the immune processes involved in peritoneal clearance and inflammation in EM patients. C5a is a potent anaphylatoxin molecule of complement associated with the development of inflammatory disorders, however its possible impact on EM development requires further investigation. The aim of this study was to determine the concentration of serum C5a in women with EM and to investigate its possible association with severity, symptoms, age and the timing of infertility. Ninety-four patients with EM (from stage I to IV) and 50 healthy controls were assessed for C5a serum levels. Clinical and demographic data were included in the analysis. C5a serum levels were higher in patients with EM than in controls (39.5 ng/mL vs. 26.0 ng/mL; p < .0001), but not different between the EM stages. No association was observed between C5a serum concentration and the presence of symptoms, age, symptom time or infertility time. The C5a serum levels were higher in patients with EM than in controls but not associated with the severity or clinical findings.
Keywords: Autoimmunity; complement system proteins; endometriosis; inflammation; pathophysiology.