Bindi Irwin was rushed to hospital for appendix surgery. But what is appendicitis?

Bindi Irwin has reportedly been rushed to hospital in the United States to undergo emergency surgery for a ruptured appendix.

According to brother Robert Irwin, “she’s going to be OK”, however the 26-year-old was forced to miss an annual gala event honouring her late father Steve Irwin.

So what is the role of the appendix, and in what circumstances can it rupture? Here’s what you need to know about appendicitis.

What is the appendix?

The appendix is a finger-like pouch attached to the large intestine. It can be found on the right of our lower abdomen.

For a long time, there was a theory that the appendix was an evolutionary remnant which may have played a role in our ancestors’ digestion, but wasn’t overly useful for modern humans following contemporary diets.

However emerging research has shown the appendix could play a role in the body’s immune function and microbiome, particularly in the gut. The gut microbiome may be disrupted by infection or antibiotics and the appendix may help the gut flora replenish and recover.

That said, most people who need to have their appendix removed to treat appendicitis do completely fine without it.

What is appendicitis, and what are the symptoms?

Appendicitis is typically a bacterial infection. Most commonly, appendicitis starts with blockage of the appendix, caused for example by a hardened piece of stool or swelling. Once blocked, bacteria in the appendix are not cleared as normal, but build up. In turn this leads to inflammation and infection of the appendix, and in some instances the appendix can burst or rupture.

The more time that elapses before someone with appendicitis is treated, the greater the risk the appendix may rupture.

Rupture is more common in children, accounting for roughly one-quarter of all cases. This is especially so for younger children, who might not have the words to describe their symptoms and might not show the classic signs, both of which can delay diagnosis.

But even in adults, sometimes the symptoms can be hard to discern from other things.

Typically, early symptoms of appendicitis can be vague, and can easily be mistaken for something else, such as viral gastroenteritis. They might include a lack of appetite, vomiting, diarrhoea, low grade fever, together with general tummy pain around the belly button.

Over hours or days the pain increases in severity and becomes localised to the right lower part of the abdomen.

How common is appendicitis?

Across the country, more than 40,000 Australians are hospitalised with appendicitis each year. The condition is responsible for around 180 of every 100,000 hospitalisations.

It’s estimated that about one in 12–15 people will experience appendicitis in their lifetime.

Appendicitis is more common in children and young people. The “peak” age group for appendicitis is between about age 10 and 30, but it can certainly happen in other age groups too.

How is appendicitis diagnosed and treated?

For the most part the diagnosis of appendicitis is made clinically – in other words, by talking to the patient and examining them. There may be a role for blood tests and scans to help make the diagnosis, but these tests may not be able to distinguish between appendicitis and other causes of abdominal pain.

For most people, appendicitis is treated with a surgery called an appendicectomy (where the appendix is removed) together with intravenous antibiotics.

Some people may be treated only with antibiotics. However research suggests removing the appendix, alongside antibiotics, is more effective.

Nowadays an appendicectomy is generally a keyhole (or laproscopic) surgery, meaning it’s minimally invasive, doesn’t leave a big scar, and sees patients back on their feet sooner.

Some patients will be able to be discharged from hospital the day after surgery, while others will stay a few days. Hospital-in-the-home is a positive alternative which can help patients get home sooner, even many children treated for a ruptured appendix.

An appendicectomy can be performed whether the appendix has burst or not. But the surgery is more complex, and the recovery longer, if the appendix has ruptured.

For a minority of people, appendicitis can have complications, for example infections and scars inside the abdomen or at the site of surgery. Untreated, appendicitis can be life-threatening and even in the setting of well-organised health systems such as ours in Australia, there are instances of death due to appendicitis. This is thankfully rare, with mortality rates as low as 0.02% of appendicetomies performed in Australia.

Fortunately, for most people, a bout of appendicitis and its treatment with surgery does not leave a long-lasting legacy and a return to full health and life is a few quieter weeks away. Hopefully this will be the case for Bindi Irwin, and we join the rest of Australia in wishing her a quick and complete recovery.