Acute Pelvic Pain
Differential Diagnosis
Common Diagnoses
- Acute Pelvic Inflammatory Disease (PID)
- Urinary Tract Infection (UTI)
- Miscarriage
- Ectopic Pregnancy
- Ovarian Cysts: Torsion, Rupture
Occasional Diagnoses
- Pelvic Abscess (Appendix, PID)
- Endometriosis
- Pelvic congestion (exacerbation of pelvic pain syndrome)
- Prostatitis (Men)
- Functional (Psychosexual origin)
Rare Diagnoses
- Misplaced IUCD (Perforated Uterus)
- Referred (e.g. Spinal Tumour, Bowel Spasm)
- Proctitis
- Invasive Carcinoma of Ovaries or Cervix
- Fibroid Degeneration
- Strangulated Femoral or Inguinal Hernia
Ready Reckoner
Key distinguishing features of the most common diagnoses
| PID | UTI | Miscarriage | Ectopic | Ovarian Cyst | |
|---|---|---|---|---|---|
| Abnormal Vaginal Bleeding | Possible | No | Yes | Possible | No |
| Purulent Discharge PV | Yes | No | No | No | No |
| Fever | Yes | Yes | No | No | No |
| Palpable Mass | No | No | Possible | No | Possible |
| Tender Uterus PV | Yes | No | Possible | No | No |
Possible Investigations
Likely:HVS, cervical swab, urinalysis, MSU, pregnancy test.
Possible:FBC, ESR/CRP, ultrasound, laparoscopy (all usually arranged by hospital admitting team).
Small Print:None.
- Urinalysis: Look for nitrites and pus cells to make diagnosis of UTI
- MSU will confirm UTI and guide antibiotic treatment.
- HVS for bacteria including gonococcus and endocervical swab for Chlamydia if purulent discharge present
- ESR/CRP: Elevated in PID.
- Pregnancy test: Positive in ectopic and miscarriage
- FBC: Raised WCC helps confirm PID and UTI if not being admitted. Also elevated in pelvic abscess
- Urgent ultrasound helpful if miscarriage or ectopic pregnancy suspected.
- Cases referred to hospital may undergo laparoscopy.
Top Tips
- In miscarriage, pain follows bleeding. In ectopic pregnancy, the sequence is usually reversed.
- Remember that there may be no bleeding with an ectopic pregnancy – or that the vaginal loss may be a light, blackish discharge.
- PV bleeding will cause haematuria on urinalysis. Only diagnose UTI if the symptoms are suggestive and urinalysis also shows nitrites and pus cells.
Red Flags
- Severe unilateral pain in very early pregnancy suggests ectopic pregnancy, even with no bleeding. Admit urgently.
- If PID does not settle within 48 hours of appropriate antibiotic treatment, consider abscess formation.
- Don’t forget to check femoral and inguinal canals for a possible strangulated hernia.