Muhammad S. Yaqub

The strength of donor-specific antibody is a more reliable predictor of antibody-mediated rejection than flow cytometry crossmatch analysis in desensitized kidney recipients.

Mujtaba MA, Goggins W, Lobashevsky A, Sharfuddin AA, Yaqub MS, Mishler DP, Brahmi Z, Higgins N, Milgrom MM, Diez A, Taber T. The strength of donor‐specific antibody is a more reliable predictor of antibody‐mediated rejection than flow cytometry crossmatch analysis in desensitized kidney recipients.
Clin Transplant 2011: 25: E96–E102.

Risk factors for native kidney dysfunction in patients with abdominal multivisceral/small bowel transplantation

Kidney dysfunction is a recognized complication after non‐renal solid organ transplantation, particularly after intestinal transplant. In our study, we reviewed data on 33 multivisceral transplant (MVT)‐ and 15 isolated small bowel (ISB)‐transplant patients to determine risk factors for kidney dysfunction. Kidney function was estimated by modified diet in renal disease (MDRD) and Schwartz formula for adults and children, respectively. Acute kidney injury (AKI) was defined as an increase in the serum Cr (sCr) greater than twofold. Kidney function declined significantly at one yr after transplantation with 46% of subjects showing an estimated GFR (eGFR) <60 mL/min. Patients with an episode of AKI were more likely to have reduced eGFR than those without AKI (p < 0.025). In linear regression analyses, age, pre‐transplant sCr, eGFR at postoperative day (POD) 30, 90, 180, 270, and tacrolimus level at POD 7 showed significant correlation with one yr post‐transplant eGFR (p < 0.05). Pediatric patients and patients with MVT had lesser decline in kidney function compared with adults or patients with ISB. In conclusion, risk factors for post‐transplant kidney dysfunction in intestinal transplantation included age, pre‐transplant sCr, AKI episode, eGFR at POD 30, 90, 180, 270, and tacrolimus level at POD 7.

BK virus nephropathy in simultaneous pancreas kidney transplant: A potentially preventable cause of kidney allograft loss

More than half of the simultaneous pancreas kidney transplant (SPK) patients afflicted with BK virus nephropathy (BKVN) lose their kidney allograft. Fear of pancreatic rejection limits the ability to reduce immunosuppression; this may result in inadequate treatment of BKVN.

Correlation between CT-based measured renal volumes and nuclear-renography-based split renal function in living kidney donors. Clinical diagnostic utility and practice patterns

Living donor evaluation involves imaging to determine the choice of kidney for nephrectomy. Our aim was to study the diagnostic accuracy and correlation between CT‐based volume measurements and split renal function (SRF) as measured by nuclear renography in potential living donors and its impact on kidney selection decision.

Impact of tacrolimus-sirolimus maintenance immunosuppression on proteinuria and kidney function in pancreas transplant alone recipients

Background Nephrotoxicity is a major complication with immunosuppression regimens used in transplantation. Calcineurin inhibitor–sparing or reduction regimens using sirolimus (SRL) have shown variable success in kidney transplantation. There is limited data on the role of SRL on native kidney function in pancreas transplantation. Methods All patients undergoing pancreas transplantation from 2003 to 2010 were enrolled in this study (n=65). Patient demographic characteristics were identified and divided into two groups: those receiving tacrolimus (Tac) in combination with mycophenolate mofetil (MMF) and those maintained on a regimen of Tac and SRL with or without MMF. The slopes for estimated glomerular filtration rate (eGFR), serum creatinine level (sCr), and proteinuria changes over time were assessed between groups. Urine protein and creatinine ratio (uPr/uCr) was used to assess proteinuria. Results There was no difference in baseline demographic characteristics. Patients were followed for a median of 3 years. Baseline sCr and eGFR were similar between groups. Differences in uPr/uCr and rate of change in sCr and eGFR were not significant between the groups overall or for any specific time. There was worsening of sCr, eGFR, and uPr/uCr within the groups over the period of study. There were no significant differences when groups were split by age or gender or when the SRL group was split further based on MMF inclusion. Conclusions Our study findings suggest that using a Tac-SRL regimen in patients with pancreas alone transplantation is a safe approach and may not lead to worsening proteinuria and kidney function when compared with regimens using Tac with MMF.

Early findings of prospective anti-HLA donor specific antibodies monitoring study in pancreas transplantation: Indiana University Health Experience

The significance of donor‐specific antibodies (DSA) is not well known in the setting of pancreas transplantation. Since December 2009, we prospectively followed pancreas transplant patients with single‐antigen‐luminex‐bead testing at one, two, three, six, and then every six months for the first two yr. Thirty‐five of the 92 patients that underwent pancreas transplantation (13 pancreas‐alone [PTA], 20 with a kidney [SPK], and two after a kidney [PAK]) agreed to participate in study. Median age at transplant was 45 yr and follow‐up was 23 months. Majority were Caucasian (n = 33) and male (n = 18). Rabbit anti‐thymocyte globulin induction was used. Median HLA‐mismatch was 4.2 ± 1.1. Eight patients (7SPK, 1PAK) developed post‐transplant DSA at median follow‐up of 76 d (26–119), 1 SPK had pre‐formed DSA. Seven patients had both class I and class II DSA, one with class I and one with class II only. Mean peak class I DSA‐MFI was 3529 (±1456); class II DSA‐MFI was 5734 (±3204) whereas cumulative DSA MFI (CI + CII) was 9264 (±4233). No difference was observed in the patient and donor demographics among patients with and without DSA. One patient in non‐DSA group developed acute cellular rejection of pancreas. From our data it appears that post‐transplant DSA in pancreas allograft recipients may not impact the early‐pancreatic allograft outcomes. The utility of prospective DSA monitoring in pancreatic transplant patients needs further evaluation and long‐term follow‐up.

Pre-transplant angiotensin receptor II type 1 antibodies and risk of post-transplant focal segmental glomerulosclerosis recurrence

Post‐kidney transplant recurrence of focal segmental glomerulosclerosis (FSGS) is a major problem. AT1R is expressed on podocyte; its expression is elevated in the proteinuric state. Using an ELISA, we tested pre‐transplant sera of 28 patients with history of idiopathic FSGS for anti‐AT1R levels and serum soluble urokinase‐type plasminogen activator receptor (suPAR) as a biomarker for risk of recurrence of FSGS. Sera from 11 patients with polycystic kidney disease (PKD) were used as controls. Twelve patients had biopsy proven post‐transplant FSGS recurrence at 1.5 months. No difference was found in the pre‐transplant suPAR levels of FSGS patients (5993 ± 2292 pg/mL) vs. PKD (7334 ± 4538 pg/mL) (p = 0.23). Serum suPAR levels in patients with FSGS recurrence (5786 ± 1899 pg/mL) vs. no FSGS recurrence (6149 ± 2598 pg/mL) (p = 0.69) were not different. Anti‐AT1R levels in patients with FSGS were 12.66 ± 11.85 U/mL vs. 8.69 ± 6.52 U/mL in PKD (p = 0.32); however, a difference was found in patients with and without FSGS recurrence 20.41 ± 14.36 U/mL 6.84 ± 4.181 U/mL, respectively (p < 0.01). Area under curve for suPAR and anti‐AT1R to predict post‐transplant FSGS recurrence was 0.51 and 0.84, respectively. Pre‐transplant anti‐AT1R levels appear to be a helpful biomarker in identifying patients at high risk of post‐transplant FSGS recurrence.

Trends and outcomes in right vs. left living donor nephrectomy: an analysis of the OPTN/UNOS database of donor and recipient outcomes – should we be doing more right-sided nephrectomies?

Discussion continues about right vs. left donor nephrectomy (LDN). Left side is preferred due to longer renal vein while right side has been associated with renal vein thrombosis and shorter vessels.

Long-term outcomes of transplant recipients referred for angiography for suspected transplant renal artery stenosis

Our aim was to study the long‐term outcomes of all transplant recipients who underwent angiography for suspected TRAS at our institution. The patients were divided into TRAS+ve and TRAS−ve groups based upon angiographically confirmed results. TRAS was confirmed in 58.1% of 74 patients with median time of 8.9 months. Primary angioplasty alone was performed in 56% of patients with TRAS, while the remaining had PTA with stent (PTAS). There was reduction in systolic and diastolic BP (165 ± 19–136 ± 15 mmHg and 82 ± 14 mmHg to 68 ± 12 mmHg; p < 0.05) and number of antihypertensive drugs (3.5 ± 0.9–2.7 ± 1.0; p < 0.05). Overall, graft survival and patient survival from time of transplant were similar in both groups. Graft function was similar for the patients with treated TRAS+ve as compared to TRAS−ve over time. Graft survival and patient survival when compared to an age‐ and year of transplant‐matched cohort control group were also similar. In conclusion, angiography for suspected TRAS is more likely to yield a confirmatory result early in the transplant course as compared to late. Treatment of TRAS in these patients had sustained long‐term graft function. Alternative etiologies of HTN and graft dysfunction should be sought for recipients further out from transplant.

Early fatal cutaneous lower extremity angiosarcoma associated with deep venous thrombosis in a renal transplant recipient

Angiosarcomas are extremely rare malignant tumors of vascular origin. We describe a 63-year-old recipient after a kidney transplant who had an angiosarcoma in the lower extremity that presented after new-onset deep venous thrombosis and was not associated with any fistula. There was rapid progression to metastasis and death. We reviewed the literature of this rare malignant tumor in kidney transplant patients.