Figure 2.

These cases illustrate the importance of an accurate diagnosis of the renal cystic disease, particularly when the renal cystic burden is not congruent with the renal function. Five cases (A–E) could have qualified as ADPKD per ultrasound/MRI imaging criteria but renal phenotype and function were inconsistent in four of them. Genetic testing revealed the presence of mutations in genes other than PKD1 or PKD2. (A) A 41 year old (y.o) man with seven and ten cysts in the right and left kidney, respectively. His htTKV was 274 ml/m. His eGFR was 48 ml/min per 1.73 m². He had a strong family history of renal cystic disease reaching ESRD (early fifth decade). Genetic studies revealed a mutation in the MUC1 gene. (B) A 29 y.o woman with bilateral renal cysts (more than ten cysts in each kidney) with htTKV of 186 ml/m. Her eGFR was 70 ml/min per 1.73 m². Her 66 y.o mother had 13 cysts on her CT scan. She was found to have a mutation in the HNF1B gene. (C) A 40 y.o woman with more than ten cysts in each kidney and htTKV of 210 ml/m and eGFR 92 ml/min per 1.73 m². She was found to have a mutation in DNAJB11. (D) A 48 y.o woman with negative family history of renal disease was found to have bilateral renal cysts incidentally on her MRI scan. Her htTKV was 179 ml/m. Her eGFR was 67 ml/min per 1.73 m². She had gout at age 44 years. She was found to have a mutation in the UMOD gene. (E) A 50 y.o woman with numerous small bilateral small cysts on ultrasound and family history of renal cystic disease and intracranial aneurysm. Her eGFR was 39 ml/min per 1.73 m². She was enrolled in Halt Progression of Polycystic Kidney Disease study B and was later found to have a mutation in DNAJB11.