From the Guidelines
A follow-up renal ultrasound is recommended to monitor your mild persistent left hydronephrosis and determine if there is intermittent obstruction causing it. Hydronephrosis refers to swelling of the kidney due to urine buildup, which can occur when urine cannot properly drain from the kidney to the bladder. Since the cause (etiology) of your condition is currently unclear, periodic imaging is necessary to track any changes and prevent potential kidney damage, as suggested by the American College of Radiology 1. The follow-up ultrasound should be scheduled within 3-6 months, depending on your symptoms and physician's assessment.
While waiting for the follow-up, ensure adequate hydration (2-3 liters of water daily), report any symptoms like flank pain, fever, or changes in urination to your doctor immediately, and take any prescribed medications as directed. If pain occurs, over-the-counter pain relievers like acetaminophen may help temporarily, but consult your doctor first. This monitoring approach is important because untreated obstruction can lead to kidney function deterioration, while mild hydronephrosis without obstruction may not require intervention beyond surveillance, as noted in recent studies 1.
Some key points to consider in the management of hydronephrosis include:
- The condition can be caused by various factors, including urolithiasis, malignant obstruction, stricture, upper urinary tract infection, and others 1.
- Imaging studies such as CT urography (CTU) and MR urography (MRU) can be useful in evaluating the cause of hydronephrosis, especially in symptomatic patients 1.
- In asymptomatic patients, ultrasound of the kidneys and bladder with Doppler imaging may be a suitable initial imaging study, as it is non-invasive and does not involve radiation exposure 1.
- Scintigraphic evaluation with mercaptoacetyltriglycine (MAG3) imaging can also be used to differentiate nonobstructive hydronephrosis from hydronephrosis due to true functional obstruction 1.
Overall, the goal of management is to prevent kidney damage and improve quality of life, and the approach should be individualized based on the patient's symptoms, underlying cause of hydronephrosis, and other factors, as emphasized in recent guidelines 1.
From the Research
Etiology of Hydronephrosis
- The etiology of hydronephrosis can be unclear, and further investigation is recommended to define the precise etiology 2.
- Hydronephrosis can be caused by various factors, including obstruction of the urinary tract, which can lead to acute kidney injury and permanent nephron loss if not corrected 3.
Diagnosis of Hydronephrosis
- Ultrasonography (US) can be used as a screening test for the diagnosis of hydronephrosis, with a diagnostic accuracy of 85.2% 4.
- Other imaging modalities, such as computed tomography (CT) and magnetic resonance imaging (MRI), can also be used to diagnose hydronephrosis 5.
- The grading scale for hydronephrosis can be used to assess the severity of the condition 5.
Follow-up and Management
- Follow-up renal US is advised to rule out intermittent obstruction in cases of mild persistent left hydronephrosis with unclear etiology.
- Patients with hematuria and weight loss should be considered as having poor predictive factors during diagnosis, and further investigation is recommended 2.
- Treatment options for hydronephrosis depend on the underlying cause and severity of the condition, and may include surgical intervention or other interventions to relieve obstruction 5.