Pelvic inflammatory disease

Pelvic inflammatory disease (PID) is an extremely broad broad term that encompasses a spectrum of infection and essentially means is infection-inflammationinflammation of the upper female genital tract, resulting in a spectrum of abnormalities. 

Epidemiology

The highest incidence is seen among sexually active women in their teens, with 75% cases being under 25 years of age.  In the United States approximately 1 million females are thought to be afflicted with pelvic inflammatory disease (PID) per year and nearly 275,000 of them are thought to be hospitalised ⁷.

Clinical presentation

More common presentations include acute pelvic pain (of variable intensity), cervical motion tenderness, vaginal discharge, fever, and leukocytosis. Right upper quadrant pain from the perihepatis in Fitz-Hugh-Curtis syndrome is possible.

Pathology

PID is defined as an acute clinical syndrome associated with ascending spread of micro-organisms, unrelated to pregnancy or surgery, from. The infection generally ascends from the vagina or cervix to the endometrium (endometritis), fallopianthen to the fallopian tubes (salpingitis), and then to and/or contiguous structures (tubo-ovarian abscess). 

It can result from number of causative organisms:

• common
  • Chlamydia trachomatis: pelvic chlamydial infection
  • Neisseria gonorrheae: pelvic gonococcal infection
  • polymicrobial infection: can account for ~30-40% of cases ³
• less common
  • Mycobacterium tuberculosis: pelvic tuberculous infection
  • Actinomyces sp.: pelvic actinomyces infection

Pelvic inflammatory disease is usually bilateral, except when it is caused by the direct extension of an adjacent inflammatory process such as appendiceal, diverticular, or post-surgical abscesses.

Radiographic features

General

Imaging features often non-specific but but are out of proportion to what may be apparent from symptomatology. May often showIf imaged early (e.g. during the cervicitis stage), there may be no finding. If imaged very late, there may be an adnexal adnexal mass like-like region with surrounding inflammatory change, and the tube and ovary may not be able to be distinguished.

Other associated findings include ⁷:

• soft-tissue stranding and infiltration of pelvic floor fascial planes
• thickening of uterosacral ligaments
• thickened/dilated fallopian tubes

Pelvic ultrasoundUltrasound

Ultrasound often only demonstrates ascitic fluid in the peritoneal cavity or, in nonspecific thickening and increased vascularity of the endometrium ⁸.

In the most severe cases, may show adnexal masses with a heterogeneous echo-pattern.

Some sonographic signs associated with tubal inflammation include:

• thickened/dilated fallopian tubes
  • incomplete septa in the tube
  • increased vascularity around the tube
  • echogenic fluid in the tube (pyosalpinx)

• cogwheel sign
• beads on a string sign

CT

CT shows a diffusely enhancing-enhancing ill-defined pelvic mass, which may be difficult to differentiate from malignancy.

Pelvic MRI

May show an ill-defined adnexal mass containing fluid with various signal intensityintensities. 

• T1 C++C (Gd): the wall and the surrounding tissues may enhance

ComplicationsTreatment and prognosis

Recognised complications of PID include:

• tubo-ovarian abscess formation
• pyosalpinx formation
• infertility
• peritonitis
• adhesion formation with resultant bowel obstruction
• Fitz-Hugh-Curtis syndrome