Appendix may play a key role in immune system: Researchers

Scientists in the US have taken a step closer to solving the mystery of the human appendix and the reason for its existence.

A team of researchers from the Midwestern University Arizona College had published a study claiming the tiny intestinal organ might work as a secondary immune organ, providing a ''safe house'' for helpful gut bacteria.

The appendix was earlier believed to exist as a forgotten organ having no obvious function, similar to wisdom teeth and the tailbone, a leftover of the evolution process that spanned millions of years.

The ''useless appendix'' concept has, however, been rebuffed in the latest study.

Mapped data on the appendix from 533 species of mammals, revealed that those with an appendix possessed ''higher average concentrations of lymphoid (immune) tissue in the cecum.'' This had led the team to believe that the appendix played a key role in the immune system, assisting the growth of beneficial gut bacteria.

The findings support what a 2012 study by researchers at Winthrop University-Hospital found that patients with Clostridium difficile colitis, a bacterial infection of the intestine and colon, were more likely to have their condition recur if their appendix had been removed.

Only 11 per cent of patients studied with an appendix saw a recurrence, as against 48 per cent without the tiny gut organ.

This was not the first time that the appendix had been associated with immune function but it was the first time that it had been statistically validated. Good bacteria are resident in the appendix, a tiny organ in the digestive tract and these bacteria help fend off infectious stomach bugs that cause diarrhea, vomiting, and abdominal pain.

The appendix had been found to be responsible for overall health improvement as it enhanced the body's natural defense system.