What is the best course of treatment for a pregnant patient with renal stone fever and potential complications such as sepsis or preterm labor?

Management of Renal Stone Fever in Pregnancy

In a pregnant patient with renal stone fever, immediate urinary tract decompression via either retrograde ureteral stenting or percutaneous nephrostomy must be performed urgently, with concurrent broad-spectrum antibiotics and close coordination with obstetrics. 1, 2

Immediate Management Algorithm

Step 1: Emergency Decompression and Infection Control

• Urgent decompression of the obstructed collecting system is mandatory when sepsis is present, as this represents a life-threatening emergency for both mother and fetus 1, 2
• Collect urine for culture and antibiogram testing both before and immediately after decompression 1
• Administer broad-spectrum antibiotics immediately, then adjust based on culture results and institutional resistance patterns 1
• Monitor closely for signs of worsening sepsis during and immediately after the decompression procedure 1
• Intensive care monitoring may become necessary 1

Step 2: Choice of Decompression Method

Retrograde ureteral stenting is the preferred first-line decompression method when technically feasible, as it provides effective drainage with minimal radiation exposure 2, 3

Alternative: Percutaneous nephrostomy (PCN) should be used when retrograde catheterization is not technically possible 2, 3

• PCN can be performed using ultrasound guidance alone to avoid radiation exposure to the fetus 1, 3
• The incidence of spontaneous abortion or preterm labor from PCN placement is exceedingly low 1, 3

Step 3: Coordinate with Obstetrics

• All interventions must be coordinated with the patient's obstetrician before proceeding 1, 2
• Monitor for signs of preterm labor, which is the most significant risk of stone disease during pregnancy 1, 2
• The risk of preterm labor completely resolves once the stone passes or is removed 1, 3

Step 4: Delay Definitive Stone Treatment

Definitive treatment of the stone must be delayed until the sepsis has completely resolved 1

• Do not attempt ureteroscopic stone removal during active infection 1
• Temporary drainage (stent or nephrostomy) should remain in place until infection clears 1

Technical Considerations for Procedures

Radiation Minimization

• Avoid fluoroscopy during stent placement whenever possible 1, 3
• Use ultrasound guidance to confirm appropriate catheter or stent positioning 1, 3
• If fluoroscopy is absolutely necessary for safe placement, use the minimum exposure required 1

Stent Management

• Pregnant patients require frequent stent exchanges (typically every 6 weeks) due to rapid encrustation 1, 2
• Stents typically remain in place until after delivery 3
• Monitor for complications including ureteral injury, perforation, or recurrent sepsis that could trigger preterm labor 1, 3

Analgesia During Pregnancy

• NSAIDs (ketorolac, diclofenac, ibuprofen) are absolutely contraindicated in pregnancy 1, 2
• Use opioids as primary analgesics: hydromorphine, pentazocine, or tramadol are preferred over pethidine 1, 2
• Pethidine has higher rates of vomiting and need for additional analgesia 1

Definitive Treatment After Infection Resolution

Once sepsis has cleared and the patient is stable:

• Ureteroscopy is the preferred definitive intervention if the stone has not passed spontaneously and symptoms persist 1, 2, 4
• Ureteroscopy can be performed safely during all trimesters of pregnancy with modern equipment and techniques 1, 4
• Extracorporeal shock wave lithotripsy and percutaneous nephrolithotomy are contraindicated during pregnancy 5

Critical Pitfalls to Avoid

• Never delay decompression in the presence of infection/sepsis - this is a true urologic emergency that can rapidly progress to maternal septic shock and fetal demise 1, 2
• Do not rely on ultrasound sensitivity alone (only 45% for ureteral stones) - clinical judgment and correlation with symptoms are essential 2
• Do not attempt definitive stone removal during active infection - this increases risk of systemic inflammatory response syndrome 1, 3
• Avoid prolonged manipulation during initial decompression procedures, as this can worsen sepsis 1