What is the significance of a computed tomography (CT) scan showing no hydronephrosis in a mature individual, as evaluated by nephrologists (kidney specialists)?

From the Guidelines

The patient's CT results showing no evidence of hydronephrosis is a positive finding, indicating no blockage causing urine to back up into the kidneys, and this is reassuring as hydronephrosis can lead to kidney damage if left untreated, as noted in the study by 1. The absence of hydronephrosis suggests that there is no obstruction in the urinary tract, which is a common cause of kidney damage. However, it is essential to consider that normal CT findings without hydronephrosis do not necessarily rule out other kidney issues, such as chronic kidney disease, glomerulonephritis, or early stages of kidney disease, which may not show structural changes visible on CT, as discussed in the study by 1. Some key points to consider in this scenario include:

• The patient should follow up with their nephrologist to discuss these results in the context of their overall kidney function, including blood tests like creatinine and GFR.
• The nephrologist may recommend regular monitoring, lifestyle modifications, or medications depending on the underlying reason for the CT scan and other clinical findings, as suggested by the study by 1.
• It is crucial to note that CT urography (CTU) is an imaging study that can help improve visualization of both the upper and lower urinary tracts, and it may be used to further evaluate the patient's kidney function, as mentioned in the study by 1. The patient's clinical context and overall health status should be taken into account when interpreting the CT results and determining the next steps in management, as emphasized in the study by 1.

From the Research

Nephrologist Care without Hydronephrosis

• Patients with hematuria without clear benign causes should be referred to urologists for workup to rule out urologic malignancies, as stated in the study 2.
• Asymptomatic microscopic hematuria after negative workup should be followed with annual urinalysis with repeat urologic evaluation if it persists after 5 years, according to the study 2.
• The management of patients with an acute stone episode is similar to that for those with hydronephrosis, and patients with first stone episodes need evaluation for risk factors for stone formation 2.

CT Results and Nephrologist Care

• Computed tomography (CT) scans can be used to diagnose hydronephrosis, and patients with incidentally found kidney masses should be referred to urology for possible intervention when they have solid kidney masses or cystic masses that need further evaluation 2.
• A CT scan can show findings suggestive of retroperitoneal fibrosis involving the ureteral region, as seen in a case study where a patient presented with severe acute kidney injury without hydronephrosis 3.

Obstructive Nephropathy without Hydronephrosis

• Urinary tract obstruction leading to acute kidney injury is usually associated with bilateral hydroureters and hydronephrosis, but atypical cases can present without these features, as seen in a case study where a patient presented with severe acute kidney injury without hydronephrosis 3.
• Suspicion is key in diagnosing obstructive nephropathy without hydronephrosis, and a high index of suspicion is necessary to diagnose and treat this condition promptly 3.