Stump appendicitis (SA) is a rare but serious complication that occurs after an appendectomy, a surgery performed to remove the inflamed appendix. This condition involves the inflammation and infection of a small portion of the appendix unintentionally left behind during the initial procedure. Although the initial surgery is intended to resolve appendicitis permanently, the residual tissue can become diseased, posing a significant health risk. Because of the potential for misdiagnosis and the high rate of associated complications, stump appendicitis is considered a dangerous condition requiring prompt medical attention.
The Mechanism of Stump Appendicitis
Stump appendicitis occurs when a segment of the appendix remains attached to the cecum, the beginning of the large intestine, following the original surgery. This remaining portion, referred to as the appendiceal stump, is typically inflamed because the surgeon was unable to completely remove the appendix flush with the cecal base. The risk of developing SA increases when the residual stump length is greater than 5 millimeters (0.5 cm).
The inflammatory process begins when the remaining stump becomes obstructed, often by a fecalith, a hardened piece of stool. This obstruction causes pressure to build up inside the stump, impairing blood flow and promoting bacterial growth. The resulting infection and inflammation mirror the process of acute appendicitis, just in a smaller, residual structure. Factors that may contribute to leaving a longer stump include severe inflammation or abscess formation during the initial appendectomy, which obscures the surgeon’s view of the appendix’s base.
Recognizing the Warning Signs
The clinical presentation of stump appendicitis closely mimics that of a standard appendicitis episode, making it difficult to distinguish without proper context. Patients typically experience abdominal pain that often localizes to the right lower quadrant, the same area where the original appendix was located. Other common symptoms include nausea, vomiting, loss of appetite, and a low-grade fever.
The timing of symptom onset is extremely varied and does not follow a predictable pattern. Symptoms can appear as early as a few days or weeks following the original appendectomy, or they may manifest decades later, with reported intervals ranging from two months up to 50 years. The crucial difference is the patient’s history of a previous appendectomy, which often leads medical providers to initially consider other causes for the abdominal pain. This prior surgical history can become a barrier to rapid diagnosis.
Why Stump Appendicitis Poses a High Risk
Stump appendicitis carries a high risk primarily because of the challenge in diagnosing it in a patient who has already undergone an appendectomy. Clinicians may overlook the possibility of SA, attributing symptoms to more common post-operative issues like scar tissue adhesions or other digestive disorders. This diagnostic delay is the largest factor increasing the potential for severe complications.
The inflammation in the stump progresses rapidly, and the delay in treatment results in a higher rate of perforation compared to typical acute appendicitis. Studies show that the perforation rate for SA can be as high as 55%, with reported ranges between 30% and 70%. Perforation leads to the release of infectious material into the abdominal cavity, which can cause abscess formation, peritonitis, and life-threatening sepsis. The increased morbidity associated with these advanced complications categorizes stump appendicitis as a dangerous condition.
Diagnosis and Definitive Treatment
Diagnosing stump appendicitis requires a high degree of clinical suspicion combined with advanced medical imaging. A Computed Tomography (CT) scan of the abdomen and pelvis is considered the most sensitive and specific imaging modality for confirming the condition. The CT scan can clearly visualize the inflamed, tubular remnant of the appendix and any associated inflammatory changes or abscesses in the surrounding tissue.
Once the diagnosis is confirmed, the definitive treatment is a surgical procedure known as a completion appendectomy. This operation involves surgically removing the remaining inflamed appendiceal stump in its entirety. Depending on the severity of the inflammation and complications like perforation, the surgeon may perform the procedure either laparoscopically or through an open incision. Pre-operative management includes administering broad-spectrum intravenous antibiotics and fluid resuscitation to stabilize the patient and control the infection before surgery.