Mild chronic renal failure with a family history of kidney disease

A 31-year-oldwoman (Figure 1: III-1) was evaluated for mild renal failure. The serum creatinine was 1.5 mg/dL and the creatinine clearance 55 mL/min (Cockcroft formula). The blood urea nitrogen and urate levels were 52 and 4.8 mg/dL, respectively. There was a mild microalbuminuria (57 mg/24 h); urinalysis was unremarkable. Renal ultrasonography showed a right kidney of 9.5 cm and a left kidney of 9.2 cm, with normal echogenicity and no cysts; Doppler examination was normal. The patient’s father (II-2) had a 20-year history of slowly progressive renal failure of unknown origin, leading to dialysis initiation at age 58. A CT scan revealed the existence of small kidneys with several cysts. One month before starting dialysis, he underwent unilateral nephrectomy for renal cell carcinoma. He had suffered a few attacks of gout starting at age 55. The father has one brother (II-4), apparently healthy. The paternal grandfather of the proband (I-1) died at age 60 of uraemia, after a history of gout and heart disease.