Kidneys
2. Findings and Diagnosis
CT Chronic Renal Failure Persistent Nephrograms
CT in the axial plane through the kidneys shows bilateral small irregular kidneys, left smaller than right with persistent nephrograms a day after a cardiac catheterization. While the larger right kidney does show some excretion into the calyces, there is no identifiable excretory phase in the left kidney. Neither the aorta nor the IVC has contrast and there is vicarious excretion of contrast in the gallbladder which is further evidence of chronic renal failure.
Ashley Davidoff MD TheCommonVein.net 130983c
CT in the axial plane through the kidneys shows bilateral small irregular kidneys, left smaller than right with persistent nephrograms a day after a cardiac catheterization. While the larger right kidney does show some excretion into the calyces, there is no identifiable excretory phase in the left kidney. Neither the aorta nor the IVC has contrast and there is vicarious excretion of contrast in the gallbladder which is further evidence of chronic renal failure.
Ashley Davidoff MD TheCommonVein.net 130983c
Findings
Delayed Function Persistant Nephrograms
Note Vicarious Excretion
Small Periphertral Cysts
🧠 Glomerulocystic Kidney Disease (GCKD) – Imaging and Clinical Features
| Feature | Details |
|---|---|
| Cyst location | Cortical, often subcapsular or peripheral |
| Cyst size | Small (<5 mm), uniform or mildly variable |
| Distribution | Diffuse or scattered across the cortex |
| Renal size | May be normal or slightly enlarged |
| Corticomedullary differentiation | Often preserved or mildly altered |
| Cause / association | – May be familial, sporadic, or syndromic – Linked with tuberous sclerosis, congenital nephrotic syndromes, or obstructive uropathy in infants |
| Clinical presentation | – Proteinuria – Renal insufficiency – Hypertension (variable onset) |
🔍 Differential Diagnosis of Small Cortical Cysts
| Condition | Key Clues |
|---|---|
| Glomerulocystic kidney disease | Small peripheral cysts Family history or syndromic features |
| Nephronophthisis | Tiny cysts at corticomedullary junction, childhood renal failure |
| Acquired cystic kidney disease | Multiple cysts, usually in chronic dialysis patients |
| Localised renal cystic disease | Unilateral, non-progressive cluster of cysts (no family history) |
| Multicystic dysplastic kidney | Nonfunctioning kidney, irregular cortex, cystic mass in neonates |
✅ Summary:
-
Small peripheral cortical cysts in an appropriate clinical context are highly suggestive of glomerulocystic kidney disease, especially in young patients or those with a relevant family or syndromic history.
-
If the renal function is stable and cysts haven’t progressed, it could also represent a stable developmental anomaly or localised cystic disease.