Two kidney-transplant women with therapy-resistant hypertension: diagnostic error of a renal artery stenosis

This was a 57-year-old woman with end-stage renal disease (ESRD) due to chronic pyelonephritis who had received a cadaver kidney graft in July 1980 after 42 months of haemodialysis. Maintenance immunosuppression included azathioprine and prednisolone. Hypertension appeared a few months after kidney transplantation (KT) and was treated by methyldopa 250 mg three times a day. A systolo-diastolic murmur was noticed 6 months after KT. A first graft arteriography was performed in 1982. It revealed parietal irregularities with a -20% stenosis involving the first 2 cm of the transplant renal artery stenosis (RAS). In 2000, hypertension became resistant to a treatment combining isradipine and atenolol. Cockroft creatinine clearance and 24 h proteinuria were 72 mlumin and 150 mg, respectively. A colour Doppler ultrasound (CDU) using a HDI 3000 machine with a 3.5 or 5 MHz sectorial transducer was performed. Peak systolic velocity (PSV) was measured at 3.36 mus in the ostial part of the transplant renal artery, raising the suspicion of the existence of transplant RAS, since truncal angle-corrected PSV above 2 mus is a generally accepted criterion for this diagnosis [1–3]. A magnetic resonance angiography (MRA) was also performed, using a breath-hold gadolinium (GD)-enhanced fast 3D gradient echo sequence with multiplanar and maximum intensity projection reconstructions (3D-GD-MRA) (1.5 Tesla Philips Gyroscan magnet). An 80% post-ostial stenosis of the transplant renal artery was demonstrated (Figure 1A). Intra-arterial digital subtraction angiography (IADSA) was then repeated. Surprisingly, the image was unchanged as compared to the examination performed 18 years earlier, showing a -20% narrowing on the upper edge of the transplant renal artery. Moreover, pressure measurement between iliac artery and transplant renal artery revealed no gradient. Notably, metal clips were present at some distance from the transplant artery (Figure 1B).