The prognostic significance of iliac vessel calcification in renal transplantation

BACKGROUND

Peripheral vascular disease and major extremity amputation are common in patients with established renal failure and are associated with considerable morbidity. Several studies have shown high rates of amputation following simultaneous pancreas-kidney transplantation, but there is minimal literature on the incidence of amputation following renal transplantation. Furthermore, there is little evidence regarding the best method of predicting which patients might be at risk of developing peripheral vascular complications after transplantation.

METHODS

We undertook a 5 year follow-up on the cohort of patients who were on our renal transplant waiting list 5 years ago (January 2007). At this time, it was standard practice within our unit for all patients to have routine pelvic x-rays to assess for vascular calcification of the iliac vessels at the time of activation onto the transplant waiting list. Any patients with moderate/severe calcification on x-ray, which may complicate transplantation, were referred for computed tomography angiogram (CTA) of their aorto-iliac vessels. Mortality, transplantation outcomes, and amputation rates at 5 years were correlated with the severity of calcification on preoperative imaging.

RESULTS

One hundred eighty-seven patients were on the waiting list for renal transplantation in January 2007 (92 men; mean age, 58.3 +/- 6.2 years). Ninety-three patients received a transplant during the subsequent 5 years. By January 2012, 82 patients had a functioning transplant, 45 remained on the waiting list (5 suspended), 40 patients had died, and 20 were alive but no longer on the waiting list. Seventy-three (39.5%) had moderate or severe calcification on plain x-ray and went on to have CTA. Of these patients, 16 (21.9%) had extensive calcification affecting all the iliac vessels and were removed from the waiting list as a result. Preoperative imaging was useful in determining the side for surgery in a further 18 patients (24.3%). Twenty-two patients developed vascular complications. Nineteen (86.4%) had moderate-severe vascular calcification on imaging. Four of the patients with vascular complications (18.2%) underwent transplantation (2 had below knee amputation (BKA) prior to transplantation; 1 developed distal ischemia on the same side as the transplantation 2 years postoperatively; 1 had bilateral above knee amputation (AKA) approximately 2 years after transplantation). Eleven (50%) of the patients with vascular complications were dead at 5 years of follow-up. Mortality and amputation rates were higher in patients with moderate-severe calcification than minimal calcification (30.1% vs 16.6%; P = .02 and 10.9% vs 1.8%; P = .003, respectively). There was no difference in rates of delayed graft function (DGF), biopsy-proven acute rejection (BPAR), or creatinine at 1 year between patients who underwent transplantation with moderate-severe calcification and those without, however, intraoperative vascular complications (26.7% vs 3%; P < .001), graft loss (28.1% vs 3.4%; P = .01), and death with a functioning transplant (9.7% vs 1.6%; P = .04) rates were higher in patients with extensive calcification compared with those without.

CONCLUSIONS

Plain x-ray of the pelvis is a useful screening tool to identify those patients who may require further detailed vascular imaging prior to transplantation. Amputation rates following renal transplantation are low and peripheral vascular disease (PVD) in isolation should not preclude transplantation. Nevertheless, significant vascular calcification is predictive of mortality both with and without transplantation and graft loss in patients with a renal transplant.

An unusual abdominal mass in an elderly patient

Adult intussusception is rare and is often not included in the differential diagnosis. Patients who have previously undergone some form of gastric bypass procedure are more susceptible. We report a case of retrograde intussusception following a Roux-en-Y gastric bypass in an elderly patient, who presented with an abdominal mass. Her initial provisional diagnosis was bowel obstruction. As the number of bariatric gastric bypass procedures continues to rise, we are likely to see more of this kind of post-operative complication. Hence, it is crucial for surgeons to consider intussusception as a cause of abdominal pain, obstruction or mass in patients who have undergone some form of gastric bypass procedure.

Lobar nephronia in a transplanted kidney

We report a patient who presented with a solid mass in her graft 15 years after renal transplantation. The appearances by ultrasound were consistent with either malignancy or lobar nephronia (focal acute bacterial nephritis). Biopsy confirmed the diagnosis of a lobar nephronia with marked inflammatory infiltrate and frank pus formation. Treatment with antibiotics was associated with resolution of the mass. Lobar nephronia is a diagnosis based upon renal ultrasonography and must be considered in a patient with a solid mass in the kidney.

FK 506 versus cyclosporin in the prevention of renal allograft rejection--European pilot study: six-week results

FK 506 was compared with cyclosporin in a randomised trial in good-risk cadaveric renal transplant recipients. The objective was to evaluate whether oral FK 506 dosing was viable and whether blood concentrations in the range 10-20 ng/ml would prove to be practical. Thirty-one adult patients were randomised to FK 506 and 16 to cyclosporin. Both groups received an identical regimen of azathioprine and corticosteroids. Serum creatinine concentrations decreased rapidly in both groups with mean values below 200 mumol/l within 2 weeks. One graft in the cyclosporin group was lost due to renal vein thrombosis. During the 6-week study period, 19.4% of patients on FK 506 and 31.3% on cyclosporin experienced acute rejection. One patient in each group experienced corticosteroid-resistant rejection that responded to anti-lymphocyte therapy. Infections were reported in 51.6% of the FK 506 group compared with 37.5% of the cyclosporin group. The spectrum of adverse events was similar in both groups. However, minor neurological disorders were more common in the FK 506 group (54.8% versus 6.3%) whereas hypertension was less common (48.8% versus 75.0%). The results indicate that oral FK 506 rapidly achieves therapeutic blood concentrations and is an effective immunosuppressant for the initial treatment of renal allograft recipients.

Metastatic calcification and cytomegalovirus infection

We report a patient who developed hypercalcaemic metastatic cutaneous calcification in association with a cytomegalovirus infection after a liver transplant. The skin nodules disappeared as the hypercalcaemia resolved and the cytomegalovirus infection subsided.