Emergency urology in pregnancy

Special considerations

• Physiological hydronephrosis, especially on the right, may mask obstruction.
• Increased risk of UTI and pyelonephritis.
• Diagnostic limitations related to ionizing radiation.

Common emergencies

• Pyelonephritis in pregnancy.
• Renal colic.
• Acute urinary retention.
• Acute cystitis.

Diagnosis

• Ultrasonography is the modality of choice.
• Noncontrast MRI if needed.
• CT is not a first-line investigation, but should not be rejected if the result will substantially change management and ultrasonography or MRI is inconclusive. Make the decision jointly with the obstetric and radiology teams, optimizing the radiation dose.
• Laboratory tests: CBC, creatinine, urinalysis, culture.

Emergency management

• Pyelonephritis: hospital admission and an antibiotic approved for the gestational age, taking account of allergies, kidney function, culture results, the local protocol, and obstetric assessment.
• Renal colic: paracetamol is the preferred analgesic under the obstetric protocol. Avoid NSAIDs where possible from 20 weeks; between 20 and 30 weeks, use only when clinically necessary, at the lowest dose and for the shortest duration, and avoid them from 30 weeks. If use exceeds 48 hours between 20 and 30 weeks, consider monitoring amniotic fluid volume.
• Persistent or infected obstruction requires urgent drainage with a stent or nephrostomy; the choice depends on anatomy, gestational age, anesthetic risk, and available expertise.
• Urinary retention: catheterization.
• In sepsis, start treatment immediately; if infected urinary tract obstruction is present, simultaneously arrange urgent urinary tract drainage.

Algorithm