How is hydronephrosis managed during pregnancy?

From the Guidelines

Management of hydronephrosis during pregnancy primarily involves conservative approaches unless complications arise, with a focus on observation, hydration, pain management, and antibiotics as needed, as supported by recent studies such as 1 and 1. The goal of management is to prevent complications such as acute kidney injury, preterm labor, and maternal or fetal death, while also minimizing the risk of interventions.

• Most cases of physiologic hydronephrosis during pregnancy require only observation and regular monitoring with ultrasound, as the condition typically resolves after delivery.
• For symptomatic patients, initial management includes:
  • Adequate hydration
  • Pain management 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) or amoxicillin-clavulanate (875/125mg twice daily) for 7-14 days should be prescribed, as suggested by 1.
• For severe cases with renal function deterioration, intractable pain, or persistent infection, temporary urinary diversion with ureteral stent placement or percutaneous nephrostomy may be necessary, as discussed in 1. These interventions are typically performed after the first trimester when possible, to minimize the risk of complications. The underlying cause of hydronephrosis during pregnancy is usually mechanical compression of the ureters by the enlarging uterus, particularly on the right side due to the anatomical positioning and the dextrorotation of the uterus, as well as hormonal influences from progesterone, which decreases ureteral peristalsis and tone, as noted in 1 and 1. Ultrasound is the first-line study for diagnosis of maternal hydronephrosis or renal anatomic abnormalities, and can help differentiate between obstructive and nonobstructive hydronephrosis, as reported in 1. In cases where intervention is necessary, a combination of renal resistive index (RI) measurement and ureteral jet evaluation may help predict the need for intervention, as suggested by 1.

From the Research

Management of Hydronephrosis During Pregnancy

Hydronephrosis during pregnancy can be managed through various approaches, including conservative and surgical methods. The primary goal is to alleviate symptoms and prevent complications while ensuring the health and safety of both the mother and the fetus.

Diagnostic Approaches

• Ultrasound is the preferred initial diagnostic tool for investigating hydronephrosis in pregnancy, as it is non-invasive and does not expose the fetus to radiation 2.
• Magnetic Resonance Imaging (MRI) can be used if the diagnosis remains uncertain after ultrasound, providing more detailed images without the use of ionizing radiation 2.
• Low-dose Computed Tomography (CT) scans may be considered in limited cases where ultrasound and MRI are inconclusive or not feasible 2.

Conservative Management

• Conservative approaches are the preferred initial management option for symptomatic hydronephrosis and ureteral calculi in well patients, including the use of analgesics, intravenous fluids, and antibiotics 3, 4.
• Positioning and analgesia can help alleviate pain and discomfort associated with hydronephrosis 4.

Surgical Interventions

• Ureteral stenting and nephrostomy can be used as intervention options when conservative management fails, with informed consent on the risks and benefits of each procedure 2, 3, 5.
• Primary ureteroscopy with definitive stone management can be safely performed in centers with appropriate expertise, offering excellent stone-free rates and symptomatic improvement 2.
• Percutaneous nephrostomy may be necessary in special cases, such as pyeloureteral stenosis or impacted ureteric stones 5.

Multidisciplinary Approach

• A multidisciplinary management approach involving renal ultrasonography, renography, and collaboration between obstetricians, anesthetists, and surgeons is recommended for the diagnosis and treatment of symptomatic hydronephrosis in pregnancy 6.
• Shared decision-making involving the patient, obstetrician, anesthetist, and surgeon is crucial at all stages of management to ensure individualized care plans 2.