Clinical meaning
Pelvic inflammatory disease (PID) is an ascending polymicrobial infection of the upper female genital tract, involving the endometrium (endometritis), fallopian tubes (salpingitis), ovaries (oophoritis), and pelvic peritoneum (peritonitis). The primary causative organisms are Neisseria gonorrhoeae and Chlamydia trachomatis, though the infection is typically polymicrobial, involving anaerobes (Bacteroides, Prevotella, Peptostreptococcus), facultative gram-negative rods (E. coli), genital mycoplasmas (M. genitalium, M. hominis), and Gardnerella vaginalis. The pathogenesis involves bacterial ascent from the lower genital tract through the cervical os into the endometrial cavity and fallopian tubes. This process is facilitated by cervical mucus disruption during menstruation, endocervical instrumentation, or bacterial mucinase production. N. gonorrhoeae directly damages ciliated tubal epithelium through lipooligosaccharide (LOS)-mediated inflammatory cascades, activating complement, recruiting neutrophils, and triggering TNF-α and IL-1β release. C. trachomatis induces a delayed-type hypersensitivity response through chlamydial heat shock protein 60 (cHSP60), which shares molecular homology with human HSP60 - this molecular mimicry drives chronic inflammatory damage and autoimmune tubal destruction even after the organism is cleared. Fitz-Hugh-Curtis syndrome occurs when infection spreads from the fallopian tubes to the liver capsule (Glisson capsule) via peritoneal or...