The pelvis is located at the lowest position within the abdominal cavity, making it prone to the accumulation of inflammatory exudates or purulent fluid, which can lead to the formation of an abscess. Due to the small surface area of the pelvic peritoneum and its limited capacity for toxin absorption, systemic toxic symptoms in cases of pelvic abscess are relatively mild.
Clinical Manifestations and Diagnosis
During the treatment of acute peritonitis, such as after appendiceal perforation or colorectal surgery, the occurrence of fever accompanied by typical rectal or bladder irritation symptoms (tenesmus, frequent small-volume stools, mucus stools, frequent urination, and dysuria) suggests the possibility of pelvic abscess.
Abdominal examination often reveals no positive findings. On rectal examination, relaxation of the anal sphincter may be noted. A bulging, tender mass, sometimes with a sense of fluctuation, can usually be palpated on the anterior wall of the rectum. In married female patients, vaginal examination may assist in diagnosis. In cases of pelvic inflammatory masses or abscesses, posterior vaginal fornix puncture can also aid in both diagnosis and treatment. Lower abdominal ultrasound, transrectal ultrasound, or transvaginal ultrasound is helpful in confirming the diagnosis. CT scans may be performed when necessary to provide additional diagnostic clarity.
Treatment
When the pelvic abscess is small or has not yet fully formed, non-surgical treatment may be employed. This includes the use of antibiotics, complemented by abdominal hot compresses, warm saline enemas, and physical heating therapies. Larger abscesses require surgical intervention. Under sacral or epidural anesthesia, the lithotomy position is adopted. Using an anoscope to expose the anterior rectal wall, after cleaning and disinfection, a long needle is used to puncture the fluctuant area and aspirate the pus. A small incision is then made at the puncture site, and a hemostat is inserted to enlarge the opening, allowing the pus to drain. A rubber drainage tube is then inserted and retained for 3–4 days. In married female patients, posterior vaginal fornix incision and drainage may be performed after puncture.