Appendicitis occurs when the appendix, a small pouch attached to the large intestine, becomes blocked, inflamed, and infected. The blockage is the primary cause and can result from several factors:

• A small piece of undigested food or hardened stool (fecalith or appendicolith) getting stuck in the appendix opening

• Swelling of lymphoid tissue in the appendix due to infection or immune response, which can obstruct the appendix

• Infections caused by viruses, bacteria, or parasites in the digestive tract that lead to inflammation and swelling, potentially blocking the appendix

• Rarely, tumors or foreign bodies can block the appendix

Once blocked, mucus builds up inside the appendix, increasing pressure and cutting off blood flow. This environment allows bacteria to multiply, causing infection and inflammation. If untreated, the appendix can become necrotic and rupture, leading to serious complications like peritonitis and sepsis

. Risk factors include being between 10 and 30 years old, male sex, and having a family history of appendicitis, although the condition itself is not directly inherited

. In summary, appendicitis is caused by obstruction of the appendix lumen, usually by fecal matter or lymphoid swelling, leading to infection and inflammation