When I started medical school, I was taught that the appendix was a useless little organ hanging off the start of the large intestine. Because of the sophistication of the modern world, the usefulness of the appendix had evolved out of existence. The theory at the time was that particulate matter from food or purely an infection blocked the appendix, causing appendicitis with a myriad of complications, including peritonitis and, rarely, death.

At one stage, it was a rule that you could not travel to the Antarctic unless you had your appendix removed.

Over the past decade, there has been emerging evidence that the appendix may well be a very important component of the immune system. Firstly, it appears that the appendix acts as a reservoir for beneficial gut bacteria. There is a much higher concentration of immune tissue in and around the appendix and the theory is that it is a safe house for beneficial bacteria to recolonise the bowel after a severe infection. For example, a common cause of childhood deaths in developing countries is infectious diarrhoea and thus the appendix could contribute healthy bacteria back into the bowel after a bout of this potentially lethal condition.

An even more surprising function of the appendix brings up the very topical concept of the Brain-Gut interaction. A study recently presented at the Digestive Disease week in San Diego, California looked at the link between having the appendix removed and Parkinson’s disease in 62 million people living in the US. Interestingly, having your appendix removed increases your risk for Parkinson’s disease three times. There is a particular protein known as alpha-synuclein which forms toxic clumps in the brain of people with Parkinson’s disease known as Lewy bodies. Interestingly this same protein is also found in the gastrointestinal tract of patients with Parkinson’s disease. The hypothesis is that the appendix through some immune function maintains lower levels of this protein and thus less Parkinson’s disease.

Finally, an interesting study from Sweden published a few years ago looked at the link between appendicectomy, tonsillectomy and risk for heart attack. This study reviewed the health history of every Swedish resident born between 1955 to 1970 with an average follow-up of just under 24 years. If your tonsils and appendix were removed before age 20, this increased the risk for a heart attack by 33% with appendicectomy and 44% with a tonsillectomy. The explanation is rather clear in that both organs are felt to play an important role in the immune system. Removing these organs changes the inflammatory response and it is possible that both the tonsils and the appendix play a role in a more appropriate inflammatory response and thus less vascular disease.

Thus, if your child develops either tonsillitis or appendicitis and the doctors involved in their care take a more conservative approach rather than rushing into surgery, they are probably doing your child a great favour in protecting them from future significant illnesses.

On Wednesday 29 May, Dr Ross Walker will be giving a talk on ‘The 5 keys to Ultimate Health’ at Sydney’s City Tattersalls Club to raise money for The Gut Foundation. Click here to buy tickets.