Most common site: Fallopian tubes (Salpingitis). This is the hallmark of PID and is responsible for the most severe long-term complications.
Epidemiology
Etiology
Pathogens
Most common: Chlamydia trachomatis, Neisseria gonorrhoeae
Risk factors
Multiple sexual partners, unprotected sex
History of prior STIs and/or adnexitis
Intrauterine devices
Patients with long-term intrauterine devices (IUDs) are at increased risk for developing an active Actinomyces infection, as evidenced by this patient’s culture that reveals acute-angle branching, gram-positive bacilli. t
Pathophysiology
Clinical features
History:
Lower abdominal or pelvic pain (bilateral, dull, constant).
Purulent or mucopurulent vaginal discharge.
Intermenstrual or postcoital bleeding (cervical friability).
Purulent cervical discharge, cervical erythema and friability.
Diagnostics
Empiric Clinical Diagnosis: Low threshold for treatment. Sexually active female at risk w/ lower pelvic/abdominal pain + ≥ 1 minimum criterion:
Cervical motion tenderness OR Uterine tenderness OR Adnexal tenderness.
Key Labs:
Urine β-hCG: First step in any reproductive-age female to r/o ectopic pregnancy.
NAAT for N. gonorrhoeae & C. trachomatis: Endocervical/vaginal swab or urine.
Saline wet mount: Abundant leukocytes (absence of WBCs strongly argues against PID).
Inflammatory markers: ↑ ESR, ↑ CRP, leukocytosis w/ left shift.
Imaging:
Pelvic Ultrasound (TVUS): Initial imaging modality of choice. Indicated if severe presentation, palpable adnexal mass, uncertain diagnosis, or failed response to initial Abx.
Findings: Thickened, fluid-filled fallopian tubes (hydrosalpinx/pyosalpinx), pelvic fluid, or complex adnexal mass (tubo-ovarian abscess).
Gold Standard / Diagnostic Confirmation:
Laparoscopy: Definitive diagnostic modality (shows tubal erythema, edema, purulent exudate); reserved for ambiguous cases, surgical emergencies, or treatment failures.