A pelvic abscess is a localized collection of pus, or infected fluid, that forms within the lower abdomen or the pelvic cavity. This pocket of infection typically develops in areas like the space between the rectum and uterus (the pouch of Douglas), the fallopian tubes, or the ovaries. Due to the risk of the infection spreading, a pelvic abscess requires immediate medical attention and urgent treatment.
Causes and Risk Factors
The most common source in women is Pelvic Inflammatory Disease (PID), an infection of the female reproductive organs that ascends from the lower genital tract. When this infection travels to the fallopian tubes and ovaries, it can lead to the formation of a tubo-ovarian abscess (TOA).
Another significant cause involves complications following abdominal or pelvic surgical procedures, such as a hysterectomy or a cesarean section, where bacteria are introduced or an existing infection is exacerbated. Infections originating from the gastrointestinal tract also frequently lead to pelvic abscesses.
Conditions like a ruptured appendix or diverticulitis can spill bacteria into the pelvic cavity. Inflammatory Bowel Disease (IBD) can also predispose individuals to abscess formation. Other risk factors include a compromised immune system or a history of sexually transmitted infections.
Recognizing the Signs
Symptoms often reflect a severe systemic infection, including high fever accompanied by chills. Malaise, nausea, and vomiting are also common.
Severe pain in the lower abdomen or pelvis is the most localized symptom, which may be sudden in onset. This pain can be constant and may worsen with movement or during sexual intercourse. In women, there may be an unusual or foul-smelling vaginal discharge or abnormal vaginal bleeding.
Pressure on nearby organs can lead to changes in bowel and bladder function. Patients may experience painful or frequent urination, diarrhea, or difficulty passing stool. A physical examination may reveal tenderness in the lower abdomen or a palpable mass in the pelvic area.
Diagnosis Procedures
Confirming the presence of a pelvic abscess begins with a thorough physical examination, often including a pelvic exam to check for tenderness or a mass. Laboratory tests identify signs of widespread infection; blood work typically shows leukocytosis (an elevated white blood cell count).
Imaging studies are the definitive tools used to locate and measure the infected fluid collection. A transvaginal or transabdominal ultrasound is often the first imaging method used, as it is non-invasive and effective for visualizing the reproductive organs. Ultrasound helps differentiate between a fluid-filled abscess and a solid mass.
For a more detailed assessment, or when the diagnosis remains uncertain, a Computed Tomography (CT) scan or Magnetic Resonance Imaging (MRI) may be performed. These techniques provide a clearer picture of the abscess’s size, structure, and exact location relative to adjacent organs. Imaging is essential for guiding drainage of the pus.
Treatment Approaches
Treatment focuses on controlling the infection with medication and physically removing the pus. The initial step involves immediate administration of broad-spectrum antibiotics, often delivered intravenously, selected to cover common pelvic pathogens until specific bacteria can be identified through culture.
For many patients, especially those with smaller abscesses or those who are otherwise stable, antibiotics alone can resolve the infection. If the abscess is large, complex, or fails to shrink after a few days of antibiotic therapy, drainage of the infected fluid becomes necessary. Drainage is a cornerstone of treatment and often involves a minimally invasive technique.
The preferred method is often image-guided percutaneous drainage, which uses ultrasound or CT imaging to precisely guide a thin needle or catheter through the skin and directly into the abscess cavity. The pus is then aspirated, and a small drainage tube may be left in place for continuous drainage. This technique offers a faster recovery time and fewer complications than traditional surgery.
Surgical drainage may be required for abscesses that are ruptured, very large, complex with multiple internal compartments, or situated in a location difficult to reach percutaneously. This may involve a minimally invasive laparoscopic procedure or, in complex cases, an open surgical approach. Following successful drainage, antibiotic treatment is typically continued for a short period to ensure the underlying infection is completely cleared.