Alternative pathway activation of complement in laparoscopic and open rectal surgery

Area of Science:

• Immunology
• Surgical Oncology

Background:

• The complement system plays a crucial role in immune responses.
• Rectal surgery can potentially trigger inflammatory pathways, including complement activation.
• Understanding complement activation in different surgical techniques is important for patient outcomes.

Purpose of the Study:

• To investigate complement system activation in patients undergoing rectal surgery.
• To compare the impact of open versus laparoscopic surgical techniques on complement activation.

Main Methods:

• Prospective, randomized study of 24 rectal cancer patients.
• Patients were assigned to either open (n=12) or laparoscopic (n=12) surgery.
• Complement activation markers (C4d, Bb, C3bc, TCC) were measured at multiple time points.

Main Results:

• Rectal surgery significantly increased alternative pathway (Bb) and terminal pathway (TCC) complement activation over time in both groups.
• Bb levels peaked early and normalized post-operatively, while TCC levels increased steadily.
• No significant differences in overall complement activation were observed between open and laparoscopic surgery, except for lower perioperative Bb levels in the laparoscopic group.

Conclusions:

• Rectal surgery activates the complement system, predominantly via the alternative pathway.
• Laparoscopic and open rectal surgery demonstrate similar patterns of complement activation.
• Minor differences in factor Bb levels suggest potentially less complement activation with laparoscopic surgery in the perioperative phase.