Life-Threatening Hematuria as Initial Presentation of a Complicated Transplant Renal Artery Pseudoaneurysm.

In this case report, we describe the clinical course of a complicated transplant renal artery (TRA) pseudoaneurysm, clinically featured by gross and massive hematuria one month after a kidney transplant was performed on a 50 year-old male patient. TRA pseudoaneurysm is a rare but potentially life-threatening complication that may result in bleeding, infection, graft dysfunction/loss, lower limb ischemia/loss, hemorrhagic shock, and death. TRA pseudoaneurysm treatment remains challenging as it needs to be tailored to the patient characteristics including hemodynamic stability, graft function, anatomy, presentation, and pseudoaneurysm features. This publication discusses the clinical scenario of massive gross hematuria that derived from a retroperitoneal hematoma which originated from an actively bleeding TRA pseudoaneurysm. This case highlights the combined approach of endovascular stent placement and subsequent transplant nephrectomy as a last resort in the management of intractable bleeding from a complicated TRA pseudoaneurysm. To the best of our knowledge, this is the first published case report of an actively bleeding TRA anastomotic pseudoaneurysm that caused a massive retroperitoneal bleed that in turn evacuated via the bladder after disrupting the ureter-to-bladder anastomosis. A temporizing hemostatic arterial stent placed percutaneously allowed for a safer and controlled emergency transplant nephrectomy.

Principles of Virtual Crossmatch Testing for Kidney Transplantation.

Human leukocyte antigens (HLAs) are the primary determinants of alloimmunity. A crossmatch test is a test that determines the immunologic risk of a recipient with a potential donor by ensuring that there are no transplant-relevant circulating antibodies in the recipient directed against donor antigens. Physical crossmatch (PXM) tests, such as complement-dependent cytotoxicity crossmatch (CDCXM) and flow cytometry crossmatch (FCXM), require mixing of patient serum and donor cells, are labor intensive, and are logistically challenging. Virtual crossmatch (VXM) test assesses immunologic compatibility between recipient and potential donor by analyzing the results of 2 independently done physical laboratory tests-patient anti-HLA antibody and donor HLA typing. The goal of VXM is pretransplant risk stratification-though there is no consensus on whether such risk assessment involves predicting the PXM result or the posttransplant outcome. Although the concept of VXM is not new, the advent of solid-phase assays for detecting circulating antibodies in the recipient directed against individual HLA and DNA-based methods for typing donor HLA specificities at a higher resolution makes the routine use of VXM a reality. Accordingly, VXM may be applied at different scenarios-both for sensitized and nonsensitized patients. Implementation of VXM-based approach has resulted in statistically significant reduction in cold ischemia time without an increase in hyperacute rejection episodes. Though there are considerable challenges, VXM is expected to be used more often in the future, depending on the transplant center's tolerance of immunologic risk.

The effect of race coefficients on preemptive listing for kidney transplantation.

Background: Race coefficients of estimated glomerular filtration rate (eGFR) formulas may be partially responsible for racial inequality in preemptive listing for kidney transplantation. Methods: We used the Scientific Registry of Transplant Recipients database to evaluate differences in racial distribution of preemptive listing before and after application of the Modification of Diet in Renal Disease (MDRD) and the Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) race coefficients to all preemptively listed non-Black kidney transplant candidates (eGFR modulation). Odds of preemptive listing were calculated by race, with Black as the reference before and after eGFR modulation. Variables known to influence preemptive listing were included in the model. Results: Among 385 087 kidney-alone transplant candidates from 1 January 2010 to 2 December 2020, 118 329 (30.7%) candidates were identified as preemptively listed (71.7% White, 19% Black, 7.8% Asian, 0.6% multi-racial, 0.6% Native American and 0.3% Pacific Islander). After eGFR modulation, non-Black patients with an eGFR ≥20 mL/min/1.73 m2 were removed. Compared with Black candidates, the adjusted odds of preemptive listing for White candidates decreased from 2.01 [95% confidence interval (95% CI) 1.78-2.26] before eGFR modulation to 1.18 (95% CI 1.0-1.39; P = 0.046) with the MDRD and 1.37 (95% CI 1.18-1.58) with the CKD-EPI equations after adjusting for race coefficients. Conclusions: Removing race coefficients in GFR estimation formulas may result in a more equitable distribution of Black candidates listed earlier on a preemptive basis.

An early experience on the effect of solid organ transplant status on hospitalized COVID-19 patients.

We compared the outcome of COVID-19 in immunosuppressed solid organ transplant (SOT) patients to a transplant naïve population. In total, 10 356 adult hospital admissions for COVID-19 from March 1, 2020 to April 27, 2020 were analyzed. Data were collected on demographics, baseline clinical conditions, medications, immunosuppression, and COVID-19 course. Primary outcome was combined death or mechanical ventilation. We assessed the association between primary outcome and prognostic variables using bivariate and multivariate regression models. We also compared the primary endpoint in SOT patients to an age, gender, and comorbidity-matched control group. Bivariate analysis found transplant status, age, gender, race/ethnicity, body mass index, diabetes, hypertension, cardiovascular disease, COPD, and GFR <60 mL/min/1.73 m2 to be significant predictors of combined death or mechanical ventilation. After multivariate logistic regression analysis, SOT status had a trend toward significance (odds ratio [OR] 1.29; 95% CI 0.99-1.69, p = .06). Compared to an age, gender, and comorbidity-matched control group, SOT patients had a higher combined risk of death or mechanical ventilation (OR 1.34; 95% CI 1.03-1.74, p = .027).

Correlation of abnormal histology with endoscopic findings among mycophenolate mofetil treated patients.

AIM: To describe all abnormal histological findings and their associated endoscopic presentation in patients using mycophenolate mofetil (MMF). METHODS: A retrospective review of all individuals prescribed MMF within 6 mo of a colonoscopy or flexible sigmoidoscopy between 07/2009 and 09/2015 was performed within Northwell Health system. Records were analyzed for age, gender, procedure indication, MMF indication, and both gross and microscopic findings. Only reports with abnormal histology were included. RESULTS: One hundred and eighty-four procedures from 170 patients were found, of which 39 met inclusion criteria. Fifty-one point three percent were female. MMF was used for solid organ transplant in 71.8%. Diarrhea was the indication for 71.8% of colonoscopies. Fifty-nine percent of reports revealed gross and microscopic abnormalities while 41.0% had only microscopic findings. Only 11 patients' reports (28.2%) indicated a specific histopathology of MMF colitis. Among the entire group, only 23.1% of abnormal histology was isolated proximal to the splenic flexure. CONCLUSION: Our results demonstrate a high rate of left sided disease and microscopic findings without gross mucosal abnormalities among patients using MMF. Also, a broader definition of MMF-colonopathy may be appropriate, with a majority of our abnormal histology falling outside of the more narrowly defined MMF-colitis category. Given the high frequency of isolated microscopic abnormalities and distal disease, sigmoidoscopy with random biopsies may be an appropriate, less invasive initial endoscopic examination in selected MMF patients.

Adenocarcinoma arising at ileostomy sites: Two cases and a review of the literature.

Total colectomy with ileostomy placement is a treatment for patients with inflammatory bowel disease or familial adenomatous polyposis (FAP). A rare and late complication of this treatment is carcinoma arising at the ileostomy site. We describe two such cases: a 78-year-old male 30 years after subtotal colectomy and ileostomy for FAP, and an 85-year-old male 50 years after colectomy and ileostomy for ulcerative colitis. The long latency period between creation of the ileostomies and development of carcinoma suggests a chronic metaplasia due to an irritating/inflammatory causative factor. Surgical excision of the mass and relocation of the stoma is the mainstay of therapy, with possible benefits from adjuvant chemotherapy. Newly developed lesions at stoma sites should be biopsied to rule out the possibility of this rare ileostomy complication.

Presurgical pulmonary evaluation in renal transplant patients.

Patients with chronic renal failure (CRF) due to various mechanisms are prone to significant pulmonary comorbidities. With the improvements in renal replacement therapy (RRT), patients with CRF are now expected to live longer, and thus may develop complications in the lung from these processes. The preferred treatment of CRF is kidney transplantation and patients who are selected to undergo transplant must have a thorough preoperative pulmonary evaluation to assess pulmonary status and to determine risk of postoperative pulmonary complications. A MEDLINE(®)/PubMed(®) search was performed to identify all articles outlining the course of pre-surgical pulmonary evaluation with an emphasis on patients with CRF who have been selected for renal transplant. Literature review concluded that in addition to generic pre-surgical evaluation, renal transplant patients must also undergo a full cardiopulmonary and sleep evaluation to investigate possible existing pulmonary pathologies. Presence of any risk factor should then be aggressively managed or treated prior to surgery.

Significance of elevated transplant renal artery velocities in the postoperative renal transplant patient.

INTRODUCTION: Non-invasive imaging studies can provide visualization of allograft perfusion in the postoperative evaluation of newly transplanted renal allografts. AIM: The purpose of our study was to evaluate the significance of elevated renal artery velocities in the immediate postoperative period. METHODS: Peak systolic velocities (PSVs) were obtained in the transplanted renal artery of 128 patients immediately after transplantation. Repeat allograft Doppler ultrasonography was performed on patients with elevated values. RESULTS: Of the 128 patients, 57 (44.5%) had severely elevated Doppler velocities >400 cm/s on the initial studies. Three patients within this category had persistently elevated values of >400 cm/s, warranting angiographic visualization of the renal vessels. Stent placement within the transplanted renal artery was required in two of these patients. There was normalization of the PSV in the remaining patients. CONCLUSIONS: Routine allograft Doppler ultrasonography in the immediate postoperative period allows for visualization of allograft perfusion. Elevated renal artery velocities in the immediate postoperative period do not necessarily represent stenosis requiring intervention. Failure of the PSV to normalize may require further intervention, and angiography continues to be the gold standard.

Transitory peaked waveforms with elevated velocities in Doppler sonography after renal transplant.

Vascular complications after a renal transplant are rare and critical. Duplex Doppler evaluation constitutes the primary imaging modality in renal transplant. Early diagnosis and appropriate intervention to address potential complications are crucial in graft survival. This report describes a 25-year-old woman who underwent a live-donor renal transplant. During a routine study 4 hours after surgery, she was found to have high peak flow velocities suggestive of stenosis. An angiogram obtained as a result of this finding showed no abnormalities. A repeat duplex Doppler sonogram performed 12 hours later revealed normal waveforms and velocities. Postrenal transplant vascular complications are rare but may represent a significant morbidity factor for patients and grafts. Peak wave forms, elevated velocities, and a tardus-parvus configuration are suggestive of vascular disorders that require aggressive evaluation. In our patient, the Doppler ultrasound, angiogram, and lack of clinical signs were compatible with a renal artery vasospasm. This entity, despite its reversibility in the majority of instances, may cause severe graft injury if it does not regress promptly.