The appendix is a small, worm-like pouch that is located at the junction between the small and the large intestines in the lower right side of the abdominal cavity. It is believed that the appendix is a vestigial organ, with no useful biological function in the human body. This conjecture is supported by the fact that surgical removal of the appendix does not seem to have any discernible effects on the normal functioning of the human body.
The appendix is not an empty pouch. It is usually teeming with bacteria, and also comes in contact with digested food wastes in the intestine. The appendix is also surrounded by the lymphatic system, which plays an important role in gut immunity. Recent research has suggested that the appendix may have certain beneficial functions for the human body after all. One of the theories suggests that the appendix might serve as a “safe house” for good commensal gut bacteria.
After a bout of dysentery or cholera, the bacteria from the appendix may help in reconstituting the normal flora of the gut. Another theory is that the appendix might be an important component of mucosal immunity in the gut, helping maintain digestive health. Despite these new theories, the most widely held belief still considers appendix as a vestigial organ that has lost its biological function during evolution of the modern humans.
What is an Appendicular Abscess?
Despite its reputation of being a useless relic of evolution, inflammation of the appendix can cause life-threatening complications. The two most common diseases that afflict the appendix in humans are appendicitis and appendicidal carcinoid tumors. Appendicitis is more common than cancers of the appendix.
Appendicitis refers to an inflammation of the appendix. The exact cause of appendicitis is not known. However, obstruction to the flow of food wastes and bacterial infection may contribute to appendicitis. Left untreated, appendicitis can lead to rupture of the appendix and spilling of the infectious contents into the peritoneum. This can cause peritonitis, shock, and eventually, death.
Abscess is one of the many complications of acute appendicitis. Other possible complications of appendicitis include appendicular masses, gangrene, rupture of appendix, and peritoneal infection. These complications are more likely to occur if there is a delay in seeking treatment following the onset of appendicitis.
Appendicular abscess is characterized by accumulation of pus in a local pocket following the rupture of the appendix. Even after rupture of the appendix, the pus remains within a pocket near the ruptured appendix. This localization of the abscess after rupture of appendix prevents the immediate spread of infection throughout the abdominal cavity.
Signs and Symptoms
The signs and symptoms of appendicular abscess are similar to that of appendicitis. There is usually a history of severe pain (colic) in the lower abdominal region on the right side (a region known as the right iliac fossa). The lower abdominal region on the right side also displays swelling. Rigidity and swelling in this area of the abdomen can be discovered during a physical examination.
Read more about appendix pain.
In addition to the localized signs and symptoms, rigor, chills, and high-grade fever may also be present in patients with abscess. Vomiting and constipation may also occur. Although possible, diarrhea is less frequent. It is important to note that these signs and symptoms are not specific to appendicular abscess. Other abscesses in the abdomen may also display similar signs and symptoms.
How does an abscess form in the appendix?
As mentioned previously, appendicular abscess is a downstream complication of untreated appendicitis. Left untreated, appendicitis in some individuals progresses to gangrene. In many such cases, the omentum and the intestines cover the gangrenous appendix, forming an appendicular mass. The suppuration process goes on within the appendicular mass. The abscess formation occurs after the rupture of the gangrenous appendicular mass.
However, even after the rupture of the appendix, the abscess remains constrained within a local pocket surrounded by the inflamed intestinal coils, caecum and omentum in the right side of lower abdominal region. Appendicular abscess may also be localized to other areas behind the caecum and within the pelvis. Even though the majority of cases of abscess occur in patients who delay treatment, appendicular abscess may also occur in patients of appendicitis who are being managed with antibiotic treatment.
Diagnosing Appendicular Abscess
Diagnosing appendicular abscess requires the use of multiple diagnostic techniques, including patient’s medical history, clinical findings, and laboratory investigations. Analysis of blood taken from patients with appendicular abscess shows an increase in the number of white blood cells, which is a general indication of infection in the body. X-ray imaging may be able to show the abscess in the appendix. However, CT scan and ultrasound are used more frequently to confirm the presence of appendicular abscess. These radiological techniques also allow an estimation of the size of the abscess.
Treatment of Appendicular Abscess
When the appendicular abscess is small and the patient is not very ill, antibiotics may be given to treat the condition. However, if the abscess is larger than four centimeters and the patient has high fever, draining the abscess becomes necessary. This is to prevent the rupture of the large appendicular abscess, which would lead to a highly dangerous infection in the peritoneum.
In order to drain the abscess, radiological techniques are used to first locate the abscess in the abdominal cavity. Depending on the location of the abscess, different routes of drainage are chosen. These routes of drainage could be through the rectum (referred to as transrectal), the vagina (referred to as transvaginal) or through the skin (referred to as percutaneous).
Transrectal or transvaginal routes of drainage are chosen when the location of the appendicular abscess is in the pelvis. A retroceacal location requires retroperitonial drainage of the abscess. An open surgical drainage (known as laparotomy) may be required in some patients. Antibiotics are also given as supportive therapy.
The removal of the appendix is done only after the patient recovers from the abscess drainage treatment. This reduces the risk of complications that might arise due to suturing of an inflamed caecum.