Outcome of kidney transplantation alone versus synchronous pancreas-kidney transplantation in type 1 diabetics

Imaging in pancreatic transplants

Pancreatic transplantation, performed alone or in conjunction with kidney transplantation, is an effective treatment for advanced type I diabetes mellitus and select patients with type II diabetes mellitus. Following advancements in surgical technique, postoperative management, and immunosuppression, pancreatic transplantation has significantly improved the length and quality of life for patients suffering from pancreatic dysfunction. While computed tomography (CT) and magnetic resonance imaging (MRI) have more limited utility, ultrasound is the preferred initial imaging modality to evaluate the transplanted pancreas; gray-scale assesses the parenchyma and fluid collections, while Doppler interrogation assesses vascular flow and viability. Ultrasound is also useful to guide percutaneous interventions for the transplanted pancreas. With knowledge of the surgical anatomy and common complications, the abdominal radiologist plays a central role in the perioperative and postoperative evaluation of the transplanted pancreas.

Role of sonography in pancreatic transplantation

Despite recent advancements in surgical technique and immunosuppressive therapy, postoperative complications of pancreatic transplantation are still common. A complex spectrum of such adverse events includes graft rejection, peripancreatic fluid collections, pancreatitis, exocrine leaks, vascular thrombosis, and hemorrhage. Sonography plays a key role in the initial evaluation of the transplanted pancreas. Gray-scale sonography, duplex Doppler imaging, and sonographic guidance for percutaneous biopsy all contribute to posttransplantation evaluation and detection of sequelae. Color and power Doppler imaging offer valuable information regarding the regional vasculature and potential vascular complications. Because gray-scale sonographic findings alone are often nonspecific, several clinical criteria, including those from biochemical analysis of the urine and serum, must be reviewed with the sonographic findings to provide a thorough evaluation of the transplanted pancreas. When used in conjunction with serologic and urinary markers, the findings from sonography can help direct management options or suggest the need for further examination. Therefore, an understanding of the spectrum of complications combined with knowledge concerning the limitations of this imaging modality are essential for proper diagnosis and effective treatment.

Dialysis, kidney transplantation, or pancreas transplantation for patients with diabetes mellitus and renal failure: a decision analysis of treatment options

Patients with type 1 diabetes mellitus and end-stage renal disease may remain on dialysis or undergo cadaveric kidney transplantation, living kidney transplantation, sequential pancreas after living kidney transplantation, or simultaneous pancreas-kidney transplantation. It is unclear which of these options is most effective. The objective of this study was to determine the optimal treatment strategy for type 1 diabetic patients with renal failure using a decision analytic Markov model. Input data were obtained from the published medical literature, the United Network for Organ Sharing registry, and patient interviews. The outcome measures were life expectancy (in life-years [LY]) and quality-adjusted life expectancy (in quality-adjusted life-years [QALY]). Living kidney transplantation was associated with 18.30 LY and 10.29 QALY; pancreas after kidney transplantation, 17.21 LY and 10.00 QALY; simultaneous pancreas-kidney transplantation, 15.74 LY and 9.09 QALY; cadaveric kidney transplantation, 11.44 LY and 6.53 QALY; dialysis, 7.82 LY and 4.52 QALY. The results were sensitive to the value of several key variables. Simultaneous pancreas-kidney transplantation had the greatest life expectancy and quality-adjusted life expectancy when living kidney transplantation was excluded from the analysis. These data indicate that living kidney transplantation is associated with the greatest life expectancy and quality-adjusted life expectancy for type 1 diabetic patients with renal failure. Treatment strategies involving pancreas transplantation should be considered for patients with frequent metabolic complications of diabetes and for those patients who favor kidney-pancreas transplantation over kidney transplantation alone. For patients without a living donor, simultaneous pancreas-kidney transplantation is associated with the greatest life expectancy.

Pancreas after kidney transplants

BACKGROUND

For certain uremic diabetic patients, a sequential transplant of a kidney (usually from a living donor) followed by a cadaver pancreas has become an attractive alternative to a simultaneous transplant of both organs. The purpose of this study was to compare outcomes with simultaneous pancreas-kidney (SPK) versus pancreas after kidney (PAK) transplants to determine advantages and disadvantages of the two procedures.

METHODS

Between January 1, 1994, and June 30, 2000, we performed 398 cadaver pancreas transplants at our center. Of these, 193 were SPK transplants and 205 were PAK transplants. We compared these two groups with regard to several endpoints, including patient and graft survival rates, surgical complications, acute rejection rates, waiting times, length of hospital stay, and quality of life.

RESULTS

Overall, surgical complications were more common for SPK recipients. The total relaparotomy rate was 25.9% for SPK recipients versus 15.1% for PAK recipients (P = 0.006). Leaks, intraabdominal infections, and wound infections were all significantly more common in SPK recipients (P = 0.009, P = 0.05, and P = 0.01, respectively, versus PAK recipients). Short-term pancreas graft survival rates were similar between the two groups: at 1 year posttransplant, 78.0% for SPK recipients and 77.9% for PAK recipients (P = not significant). By 3 years, however, pancreas graft survival differed between the two groups (74.1% for SPK and 61.7% for PAK recipients), although this did not quite reach statistical significance (P = 0.15). This difference in graft survival seemed to be due to increased immunologic losses for PAK recipients: at 3 years posttransplant, the incidence of immunologic graft loss was 16.2% for PAK versus 5.2% for SPK recipients (P = 0.01). Kidney graft survival rates were, however, better for PAK recipients. At 3 years after their kidney transplant, kidney graft survival rates were 83.6% for SPK and 94.6% for PAK recipients (P = 0.001). The mean waiting time to receive the pancreas transplant was 244 days for SPK and 167 days for PAK recipients (P = 0.001).

CONCLUSIONS

PAK transplants are a viable option for uremic diabetics. While long-term pancreas graft results are slightly inferior to SPK transplants, the advantages of PAK transplants include the possibility of a preemptive living donor kidney transplant, better long-term kidney graft survival, significantly decreased waiting times, and decreased surgical complication rates. Use of a living donor for the kidney transplant expands the donor pool. Improvements in immunosuppressive regimens will hopefully eliminate some of the difference in long-term pancreas graft survival between SPK and PAK transplants.