Etiology and Pathology
Most cases of chronic appendicitis originate from acute appendicitis, though a small number may begin as a chronic process. The primary pathological changes involve varying degrees of fibrosis in the appendiceal wall and infiltration of chronic inflammatory cells. The mucosal and muscularis layers often show infiltration mainly by lymphocytes and eosinophils, replacing the polymorphonuclear leukocytes typically observed during acute inflammation. Foreign-body giant cells may also be present within the appendiceal wall. Additionally, due to fibrous tissue proliferation and increased fatty deposits, the appendiceal wall may thicken, and the lumen may become narrowed, irregular, or even obstructed. These changes impair the emptying of the appendix and may compress nerves within the appendiceal wall, leading to symptoms of pain. Many patients with chronic appendicitis have appendiceal fecaliths, appendiceal adhesions, or excessive lymphoid follicular hyperplasia resulting in lumen narrowing.
Clinical Manifestations and Diagnosis
Patients often have a history of previous acute appendicitis episodes, though the symptoms may have been mild or atypical. Right lower abdominal pain is frequently reported, though some patients describe only a dull ache or discomfort. Acute exacerbations may be triggered by vigorous physical activity or irregular dietary habits. Some patients also report a history of recurrent acute exacerbations.
The key clinical sign is localized tenderness in the region of the appendix, which tends to be persistent and well-defined anatomically. In a small number of cases, a cord-like mass may be palpable in the right lower abdomen when the patient is examined in the left lateral decubitus position. Barium enema X-ray studies may confirm the diagnosis of chronic appendicitis if findings include signs such as appendiceal deformation, twisting, irregular or rough edges, or segmented changes, along with one or multiple filling defects. Thin-slice CT scans can reveal findings such as appendiceal fecaliths, irregular thickening of the lumen, or adhesions, providing additional diagnostic support.
Treatment
Once the diagnosis is confirmed, appendectomy is required, followed by histopathological examination to substantiate the diagnosis.