How is hydronephrosis managed in pregnancy?

From the Guidelines

Management of hydronephrosis during pregnancy primarily involves conservative approaches unless complications arise, with a focus on regular monitoring with ultrasound and intervention only when necessary to prevent morbidity, mortality, and impact on quality of life. Most cases of physiologic hydronephrosis in pregnancy require only observation, as the condition typically resolves after delivery 1. For symptomatic patients, initial management includes:

• Adequate hydration
• Pain control with acetaminophen (500-1000mg every 6 hours as needed)
• Position changes such as lying on the side opposite to the affected kidney If urinary tract infection develops, appropriate antibiotics like cephalexin (500mg four times daily for 7-14 days) or amoxicillin-clavulanate (875/125mg twice daily for 7-14 days) should be prescribed 1. For severe cases with persistent pain, fever, or impaired renal function, temporary drainage with a ureteral stent or percutaneous nephrostomy may be necessary, with the choice of intervention guided by the severity of symptoms and the presence of underlying kidney dysfunction, as indicated by renal resistive indices (RI) on renal ultrasound 1. Double-J stents typically require replacement every 4-6 weeks due to rapid encrustation during pregnancy. Percutaneous nephrostomy (PCN) can safely provide temporary urinary tract decompression when ureteral catheterization is not technically possible, with a low incidence of spontaneous abortion or preterm labor related to PCN tube placement 1. Regular follow-up is essential, with more frequent monitoring in the third trimester when physiologic hydronephrosis typically peaks due to maximum uterine compression of the ureters. Key considerations in the management of hydronephrosis during pregnancy include:
• The use of ultrasound as the first-line imaging modality to diagnose and monitor hydronephrosis
• The measurement of renal resistive indices (RI) to distinguish between benign pregnancy-related hydronephrosis and pathologic causes of urinary tract dilation
• The potential need for temporary drainage with a ureteral stent or percutaneous nephrostomy in severe cases
• The importance of regular follow-up and monitoring to prevent complications and ensure the best possible outcomes for both the mother and the fetus.

From the Research

Management of Hydronephrosis in Pregnancy

• Hydronephrosis in pregnancy is a condition that requires careful management to prevent complications such as premature labor, fetal loss, and caesarian sections 2.
• The management of symptomatic hydronephrosis in pregnancy typically involves a multidisciplinary approach, including renal ultrasonography to verify hydronephrosis and renography to diagnose obstructive hydronephrosis 3.
• Conservative management is often the preferred initial approach, including regular analgesia, positioning, and antibiotics, with close follow-up using ultrasound 4.
• Intervention with ureteric stent insertion or nephrostomy tube insertion may be necessary in certain cases, such as persistent pain or pyonephrosis 5, 6.

Diagnostic Approaches

• Ultrasound is the cornerstone of initial investigation for hydronephrosis in pregnancy, with MRI and low-dose CT imaging used in reserve if the diagnosis remains uncertain 2.
• Renal ultrasonography can verify hydronephrosis, while renography can diagnose obstructive hydronephrosis 3.
• Sonographically guided percutaneous nephrostomy is a safe and effective method for treating pregnant women with symptomatic obstructive hydronephrosis associated with pyosepsis or azotemia 6.

Treatment Options

• Conservative management is successful in most cases, but intervention may be necessary in certain cases, such as persistent symptoms or pyonephrosis 4.
• Ureteral double-J stenting or percutaneous nephrostomy are effective and safe treatment methods in the minority of patients with persistent symptoms not responding to conservative management 5, 4.
• Primary ureteroscopy with definitive stone management can safely deliver excellent stone-free rates and symptomatic improvement in centers with the appropriate expertise 2.