The complement system: history, pathways, cascade and inhibitors.

Since its discovery in the 19th century, the complement system has developed into a clinically significant entity. The complement system has been implicated in a variety of clinical conditions, from autoimmune diseases to ischemia-reperfusion injury in transplantation. This article charts the historical progress of our understanding of the complement system and provides a synopsis on the activation pathways and its inherent regulators.

Natural orifice translumenal endoscopic surgery (N.O.T.E.S).

Natural orifice translumenal endoscopic surgery (N.O.T.E.S) is a technique that allows access to the peritoneal cavity through natural orifices (oral, rectal, vaginal, vesical) without passing through the anterior abdominal wall. Rapid strides have been made in developing this technique, especially in animal models. Majority of research work in this field is originating from USA, while human clinical trials are being reported from India and Southern America. Morbidly obese patients and ITU patients are two target groups where N.O.T.E.S if implemented, will have the highest potential and bearing. With increasing evidence of safe practice in human models, questions on indications and feasibility of practice need to be addressed by rigorous research, strong evidence and collaboration between surgical centers worldwide.

Immunoprophylaxis in asplenic patients.

The asplenic patient is at risk of overwhelming post-splenectomy infection (OPSI) due to encapsulated bacteria, namely pneumococcus, haemophilus influenza B and meningococcal C pathogens. The lifetime risk is 1-2% with the estimated mortality being in the region of 40-70% (Davidson RN, Wall RA. Prevention and management of infections in patients without a spleen. Clin Microbiol Infect 2001;7:657-60). Preventative measures include appropriate prophylactic vaccination, long term antibiotics and patient education. Guidelines for the prevention and treatment of infection in patients with an absent or dysfunctional spleen were first published by the British Committee for Standards in Haematology in 1996, with a revised edition published in 2002. There are a number of permutations of these guidelines published by a number of professional bodies and consequently this has led to variable adherence rates to such guidelines. We review the perioperative administration of prophylactic vaccinations.