Clinical impact of pre-kidney transplant pulmonary hypertension on post-transplant outcomes.

Outcomes of kidney transplant (KT) patients with pre-transplant pulmonary hypertension (PH) are poorly understood. PH patients are often considered high risk and excluded from KT. We investigated the association of pre-transplant PH with KT recipient's outcomes. A single-center, retrospective study that reviewed all patients transplanted from 2010 to 2016, who had a transthoracic echocardiogram (TTE) before KT and at least one TTE post-KT. The TTE closest to the KT was used for analyses. PH is defined as pulmonary artery systolic pressure (PASP) ≥ 40 mm Hg. Of 204 patients, 61 had PASP ≥ 40 mm Hg (with PH) and 143 had PASP < 40 mm Hg (without PH) prior to KT. No statistically significant differences existed between the two groups in baseline demographics, renal failure etiologies, dialysis access type, and cardiovascular risk factors. The mean difference in pre-KT PASP was 18.1 ± 7 mm Hg (P < 0.001). Patients with PH had a statistically significant decrease in PASP post-KT compared to the patients without PH with a mean change of -7.03 ± 12.28 mm Hg vs. + 3.96 ± 11.98 mm Hg (p < 0.001), respectively. Moderate mitral and moderate-severe tricuspid regurgitation were the only factors found to be independently associated with PH (p = 0.001) on multivariable analysis. No statistically significant difference was notable in patient survival, graft function, and creatinine post-KT in both groups. PH pre-KT particularly mild-moderate PH did not adversely affect intermediate (90-day) and long-term allograft and patient survival. Patients with mild-moderate PH should not be excluded from KT.

Mucormycosis in a renal transplant recipient: case report and comprehensive review of literature.

Mucormycosis is a rare but devastating infection. We present a case of fatal disseminated mucormycosis infection in a renal transplant patient. Uncontrolled diabetes mellitus and immunosuppression are the major predisposing factors to infection with Mucorales. Mucorales are angioinvasive and can infect any organ system. Lungs are the predominant site of infection in solid organ transplant recipients. Prompt diagnosis is challenging and influences outcome. Treatment involves a combination of surgical and medical therapies. Amphotericin B remains the cornerstone in the medical management of mucormycosis, although other agents have been used. Newer agents are promising.

Safety of regadenoson as a pharmacologic stress agent for myocardial perfusion imaging in chronic kidney disease patients not on hemodialysis.

BACKGROUND: Pharmacokinetic studies suggest delayed clearance of Regadenoson (REG), a new selective A2A receptor agonist in chronic kidney disease (CKD). The safety of REG in large series of CKD patients in daily clinical practice remains unstudied. METHODS: Retrospective study of patients with eGFR < 60 mL/min (n = 411, Grp 1, CKD) were compared to patients with eGFR ≥ 60 mL/min (n = 638, Grp 2, Control) undergoing REG-SPECT from Jan to Nov 2009. Patient demographics, REG-SPECT data, side effects, and arrhythmia occurrences were evaluated. RESULTS: No major adverse events were noted immediately after REG-SPECT or at 1 week of follow-up. There were no differences in any arrhythmias in between the two groups (Grp 1, 47.2% vs Grp 2, 42.9%, P = ns). Ninety-nine percent of arrhythmias in CKD patients were PACs or PVCs. Transient junctional rhythm was observed in one CKD patient. There were no occurrences of second degree or higher degree AV block. Grp 1 had a blunted heart rate response (16.6 ± 16.1 vs 24.9 ± 20.3 bpm, P ≤ .001) and greater systolic blood pressure drop response (-7.4 ± 21.1 vs -1.4 ± 20.9 mm Hg, P ≤ .001) compared to Grp 2. Transient headache was more in Grp 2 (15.8% vs 22.6%, P ≤ .007). Aminophylline use to ward-off the side effects was comparable (9.5% vs 9.9%, P = ns). CONCLUSION: REG-SPECT can be safely performed in CKD non-dialysis patients with excellent tolerability, minimal side effects, and favorable hemodynamic responses compared to control group.

Coronary computed tomography angiography in dialysis patients undergoing pre-renal transplantation cardiac risk stratification.

BACKGROUND: This study addresses the safety, feasibility, and interpretability of coronary computed tomography angiography (CCTA) in excluding significant coronary artery disease in end-stage renal disease patients on dialysis undergoing pre-renal transplant cardiac risk evaluation. METHODS: Twenty nine patients (55.5 +/- 10.2 years) undergoing cardiac risk assessment prior to renal transplantation, underwent research CCTA with calcium scoring and formed the study group. All CCTAs were performed using retrospective acquisition, with beta-blockade provided one hour prior to scanning. RESULTS: No major complications occurred in this group up to 30 days after CCTA. Of the total of 374 segments interpreted by both readers, only 36 (10%) were uninterpretable by both readers. Of these, 31 (86%) were from distal segments or branches. On a segmental level, there was 95% concordance between both readers for < 50% stenosis detection. Only three out of 28 (11%) CCTAs were deemed uninterpretable. Ten patients (36%) had zero calcium score, despite being on dialysis with no evidence of obstructive coronary artery disease by CCTA. CONCLUSIONS: CCTA is feasible and safe in end-stage renal disease dialysis patients with the advent of 64-slice CCTA. Despite significant calcium burden, there was excellent inter-observer agreement at segment level for the left main and all three proximal-mid coronary arteries in excluding obstructive coronary artery disease (> 50% stenosis).

Coronary risk assessment and management options in chronic kidney disease patients prior to kidney transplantation.

Cardiovascular disease remains the most important cause of morbidity and mortality among kidney transplant recipients. Nearly half the deaths in transplanted patients are attributed to cardiac causes and almost 5% of these deaths occur within the first year after transplantation. The ideal strategies to screen for coronary artery disease (CAD) in chronic kidney disease patients who are evaluated for kidney transplantation (KT) remain controversial. The American Society of Transplantation recommends that patients with diabetes, prior history of ischemic heart disease or an abnormal ECG, or age >/=50 years should be considered as high-risk for CAD and referred for a cardiac stress test and only those with a positive stress test, for coronary angiography. Despite these recommendations, vast variations exist in the way these patients are screened for CAD at different transplant centers. The sensitivity and specificity of noninvasive cardiac tests in CKD patients is much lower than that in the general population. This has prompted the use of direct diagnostic cardiac catheterization in high-risk patients in several transplant centers despite the risks associated with this invasive procedure. No large randomized controlled trials exist to date that address these issues. In this article, we review the existing literature with regards to the available data on cardiovascular risk screening and management options in CKD patients presenting for kidney transplantation and outline a strategy for approach to these patients.

Stress echocardiography for risk stratification in patients with end-stage renal disease undergoing renal transplantation.

BACKGROUND: The predictive accuracy of stress echocardiography (SE) for adverse cardiac events has been variable in the population with end-stage renal disease undergoing renal transplantation (RT). METHODS: We performed a retrospective study of 149 patients who had pretransplant SE before RT between 1997 and 2003. Patients were followed up for a mean of 2.85 years for major adverse cardiovascular events (MACE). RESULTS: Of 149 patients studied, 139 had a negative SE, 65% were African American; 12 underwent cardiac catheterization. Only 1 patient required pre-RT revascularization. Sixteen MACE occurred over the follow-up period. SE had 37.5% sensitivity, 95.3% specificity, 33.3% positive predictive value, and 96.1% negative predictive value for MACE in the first year post-RT. First-year posttransplant event rates were 4.0% versus 30% (P < .001) for patients with a negative SE and positive SE, respectively. Multivariate predictors of MACE were positive SE (hazard ratio [HR] 7.64), hemoglobin less than 11 g/dL post-RT (HR 4.44), and calcium channel blocker use posttransplant (HR 2.90). CONCLUSIONS: A negative SE has low incidence of MACE in this intermediate- to high-risk patient subset. A positive SE predicts a sevenfold higher risk of cardiovascular events regardless of the need for revascularization before the transplant.

Infectious complications in renal transplant recipients.

Post-kidney transplant infection is the most common life-threatening complication of long-term immunosuppressive therapy. Optimal immunosuppression, in which a balance is maintained between prevention of rejection and avoidance of infection, is the most challenging aspect of posttransplantation care. The study of infectious complications in immunologically compromised recipients is changing rapidly, particularly in the fields of prophylactic and preemptive strategies, molecular diagnostic methods, and antimicrobial agents. In addition, emerging pathogens such as BK polyomavirus and West Nile flavivirus infections and the introduction of newer immunosuppressive agents that constantly change the risk profiles for opportunistic infections has added layers of complexity to this burgeoning field. Although remarkable progress has been made in these disciplines, comprehensive understanding of the clinical manifestations of infections remains limited, and the standardization of prophylaxis, diagnosis, and treatment of most infections is yet inadequately defined. The long-term goal for optimal care of transplant recipients, with respect to infection, is the prevention and/or early recognition and treatment of infections while avoiding drug-related toxicities.

The burden of chronic kidney disease in renal transplant recipients.

The National Kidney Foundation has developed guidelines for the diagnosis and classification of chronic kidney disease (CKD) but it is not known whether these are applicable to renal transplant recipients. This study determined the prevalence of CKD according to the stages defined in the guidelines, the complications related to CKD and whether the prevalence of complications was related to CKD stage in 459 renal transplant recipients. CKD was present in 412 patients (90%) and 60% were in CKD Stage 3 with a glomerular filtration rate (GFR) between 30 and 59 mL/min/1.73 m2. The prevalence of anemia increased from 0% in Stage 1 to 33% in Stage 5 (p<0.001). Hypertension was present in 86% and increased from 60% in Stage 1 to 100% in Stage 5 (p=0.02). The number of anti-hypertensives per patient increased from 0.7 in Stage 1 to 2.3 in Stage 5 (p<0.001). The number of CKD complications per patient increased from 1.1 in Stage 1 to 2.7 in Stage 5 (p<0.001). We conclude that CKD and the complications of CKD are highly prevalent in renal transplant recipients. The classification of renal transplant patients by CKD stage may help clinicians identify patients at increased risk and target appropriate therapy to improve outcomes.

Outcome of plasma exchange therapy in thrombotic microangiopathy after renal transplantation.

Thrombotic microangiopathy (TMA) in renal transplant recipients is commonly associated with calcineurin inhibitors (CNIs), though several factors such as vascular rejection, viral infections and other drugs may play a contributory role. We report a series of 29 patients with TMA, all of whom were on CNIs. Though plasma exchange (PEx) is widely used to treat TMA, therapeutic guidelines are not well defined. All our patients were treated with PEx and discontinuation of CNIs. Thrombotic microangiopathy was diagnosed at a median of 7 days post-transplant. The mean decrease in Hgb and platelets during TMA was 66% and 64%, respectively, and peak serum creatinine during TMA was 7.4 +/- 2.9 mg%. Mean duration of PEx therapy was 8.5 (range 5-23) days. Recovery of platelet count to 150K/mcL and Hgb to 8-10 g/dL were used as endpoints for PEx. Twenty-three/29 (80%) patients recovered graft function after PEx. Twenty/23 (87%) patients who recovered were placed back on CNl. Nineteen/20 (95%) patients tolerated reinstitution of CNl without recurrence of TMA. In post-transplant TMA, PEx was associated with a graft salvage rate of 80%, reversal of hematological changes can be used as the endpoint for PEx therapy and CNl can be reintroduced without risk of recurrence in the majority of patients.