Pelvic inflammatory disease

Pelvic inflammatory disease (PID) is an extremely broad term and essentially means is infection - inflammation 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 ⁷. 

Pathology

PID is defined as an acute clinical syndrome associated with ascending spread of micro-organisms, unrelated to pregnancy or surgery, from the vagina or cervix to the endometrium, fallopian tubes and / or contiguous structures. 

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 are out of proportion to what may be apparent from symptomatology.

Pelvic ultrasound

Ultrasound often only demonstrates ascitic fluid in the peritoneal cavity or, in the most severe cases, may show adnexal masses with a heterogeneous echopattern

Some sonographic signs associated with tubal inflammation include

• cogwheel sign
• beads on a string sign

CT

CT shows diffusely 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 intensity. 

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

Complications

Recognised complications of PID include

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

See also

• endometritis
• salpingitis