Pseudomonas aeruginosa bacteremia over a 10-year period: multidrug resistance and outcomes in transplant recipients

Abstract: Aim. Transplant recipients are at risk for hospital‐acquired infections (HAIs), including those caused by Pseudomonas aeruginosa. Of all HAIs, bloodstream infection (BSI) remains one of the most life‐threatening. Methods. Over a 10‐year period, we studied 503 patients, including 149 transplant recipients, with pseudomonal BSI from the University of Pittsburgh Medical Center. Trends in antimicrobial susceptibility, risk factors for multidrug resistance (MDR), and outcomes were compared between transplant and non‐transplant patients. Results. Resistance to all antibiotic classes was significantly greater in pseudomonal blood culture isolates from transplant compared with non‐transplant patients (P<0.001). Of isolates from transplant recipients (n=207), 43% were MDR, compared with 18% of isolates from non‐transplant patients (n=391) (odds ratio [OR] 3.47; 95% confidence interval [CI] 2.34–5.14, P<0.001). Among all patients, independent risk factors for MDR P. aeruginosa BSI included previous transplantation (OR 2.38; 95% CI 1.51–3.76, P<0.001), hospital‐acquired BSI (OR 2.41; 95% CI 1.39–4.18, P=0.002), and prior intensive care unit (ICU) admission (OR 2.04; 95% CI 1.15–3.63, P=0.015). Mortality among transplant recipients was 42%, compared with 32% in non‐transplant patients (OR 1.55; 95% CI 0.87–2.76, P=0.108). For transplant recipients, onset of BSI in the ICU was the only independent predictor of mortality (OR 8.00; 95% CI 1.71–37.42, P=0.008). Conclusions. Transplant recipients are at greater risk of MDR P. aeruginosa BSI, with an appreciable mortality. Future management must concentrate on the implementation of effective preventative strategies.     

Risk factors for Pneumocystis jirovecii pneumonia in kidney transplant recipients and appraisal of strategies for selective use of chemoprophylaxis

M.G.J. de Boer, F.P. Kroon, S. le Cessie, J.W. de Fijter, J.T. van Dissel. Risk factors for Pneumocystis jirovecii pneumonia in kidney transplant recipients and appraisal of strategies for selective use of chemoprophylaxis.
Transpl Infect Dis 2011: 13: 559–569. All rights reserved Abstract: Risk stratification‐based duration of trimethoprim‐sulfamethoxazole (TMP‐SMX) chemoprophylaxis to prevent Pneumocystis pneumonia (PCP) in kidney transplant recipients is not a universally adapted strategy and supporting evidence‐based sources are limited. We performed a large retrospective study to identify risk factors for PCP in kidney transplant recipients and to define parameters for use in clinical prophylaxis guidelines. Fifty consecutive patients with confirmed PCP and 2 time‐matched controls per case were enrolled. All patients were participants of the kidney transplantation program of the Leiden University Medical Center, a tertiary care hospital in the Netherlands. Potential risk factors were compared between groups by uni‐ and multivariate matched analyses. At transplantation, age >55 years (adjusted odds ratio [OR] 2.7, 95% confidence interval [CI] 1.3–5.9) and not receiving basiliximab induction therapy (adjusted OR 4.3, 95% CI 1.1–17.1) predicted development of PCP. In the final multivariate analysis, only cytomegalovirus infection (adjusted OR 3.0, 95% CI 1.2–7.9) and rejection treatment (adjusted OR 5.8, 95% CI 1.9–18) were found to be independently associated with PCP. Using the variables identified by the multivariate analyses, effects of different hypothetical chemoprophylaxis strategies were systematically evaluated. Exploring different scenarios showed that chemoprophylaxis in the first 6 months for all renal transplant patients – and during the first year posttransplantation for patients >55 years of age or those treated for rejection – would result in very low PCP incidence and optimal avoidance of TMP‐SMX toxicity. The results provide a rationale for further prospective study on targeted provision of chemoprophylaxis to prevent PCP in kidney transplant patients.     

Pneumocystis jirovecii pneumonia is rare in renal transplant recipients receiving only one month of prophylaxis

Prophylaxis against Pneumocystis jirovecii pneumonia (PCP) is recommended for at least 4–12 months after solid organ transplant. In our center, renal transplant recipients receive only 1 month of post‐transplant trimethoprim–sulfamethoxazole, which also may provide limited protection against Nocardia. We identified only 4 PCP cases and 4 Nocardia cases in 1352 patients receiving renal and renal‐pancreas transplant from 2003 to 2009 at the University of Michigan Health System. Two PCP cases were identified <1 year after transplant, and 2 PCP cases were identified >1 year after transplant (gross attack rate 4/1352, 0.3%). Two Nocardia cases were identified <1 year after transplant, and 2 cases were identified >1 year after transplant. All identified cases received induction therapy (7 of 8 with anti‐thymocyte globulin), whereas about one‐half of all renal transplant patients received induction therapy at our institution. No patient was treated for rejection within 6 months of PCP; 2 of 4 patients with PCP had recent cytomegalovirus infection. All patients with PCP and 3 of 4 patients with Nocardia survived. The benefits of prolonged PCP prophylaxis should be weighed against the adverse events associated with prolonged use of antimicrobials.     

Absence of Pneumocystis jiroveci pneumonia in liver transplantation recipients receiving short‐term (3‐month) prophylaxis

Abstract: Pneumocystis jiroveci (formerly known as Pneumocystis carinii) is a fungal pathogen that causes pneumonia (PCP) in liver transplant recipients. Consequently, prophylaxis with trimethoprim–sulfamethoxazole (TMP/SMZ) is typically administered for at least 1 year at most liver transplant programs. At our center we have utilized a short‐term (3‐month) prophylactic regimen with TMP/SMZ for the past decade and report our experience and speculate on the potential widespread application of this approach. Methods. For patients transplanted at our center between January 1997 and January 2007, we recorded all documented PCP infections by review of our liver transplant database and hospital‐based electronic medical records system, both of which record all infections and culture results. Results. We recorded no cases of PCP in any of the liver transplant recipients at our center during the study period. Conclusions. We report the absence of PCP in a large cohort of liver transplant recipients receiving a short‐term (3‐month) prophylaxis with TMP/SMZ. These findings provide a rational basis to consider short‐term (3‐month) PCP prophylaxis or avoidance of prophylaxis altogether in selected low‐risk patients.     

Risk factors for enterococcal bacteremia in allogeneic hematopoietic stem cell transplant recipients

M. Mikulska, V. Del Bono, R. Prinapori, L. Boni, A.M. Raiola, F. Gualandi, M.T. Van Lint, A. Dominietto, T. Lamparelli, P. Cappellano, A. Bacigalupo, C. Viscoli. Risk factors for enterococcal bacteremia in allogeneic hematopoietic stem cell transplant recipients.
Transpl Infect Dis 2010: 12: 505–512. All rights reserved Abstract: Bacteremia is a well known cause of morbidity and mortality in hematopoietic stem cell transplant (HSCT) recipients and enterococci are among the most frequently isolated pathogens. The aim of this study was to identify risk factors for enterococcal bacteremia during the first 30 days after allogeneic HSCT. A retrospective case–control study was performed; for each case, 3 controls were randomly selected among 306 patients transplanted during the study period (January 1, 2004 to December 31, 2007). Odds ratios (OR) with 95% confidence intervals (CI) were calculated for variables influencing the risk for bacteremia. Overall, 33 patients developed enterococcal bacteremia, within a median of 9 days after HSCT (range, 2–24). The cumulative incidence was 10.8%. Multivariate analysis identified the following variables as risk factors for enterococcal bacteremia: donor and transplant type (greater risk for mismatched related or cord blood) (OR=8.98, 95% CI, 1.65–48.99 and OR=7.52, 95% CI, 1.56–36.31, respectively, P=0.047); severe (grades 3–4) mucositis (OR=9.04, 95% CI, 1.97–41.52, P=0.018); pharyngeal enterococcal colonization (OR=4.48, 95% CI, 1.11–18.03, P=0.035); and previous empirical therapy with cephalosporins (OR=4.16, 95% CI, 0.93–18.66 for 1–7 days of therapy, and OR=7.31, 95% CI, 1.78–30.12 for 8–23 days, P=0.018). Higher Karnofsky score (≥50) and previous empirical therapy with glycopeptides were associated with a decreased risk (OR=0.25, 95% CI, 0.06–0.97, P=0.045 and OR=0.11, 95% CI, 0.02–0.59, P=0.010, respectively). The crude mortality at 7 and 30 days was 12% (4/33) and 24% (8/33), respectively. Enterococcal bacteremia is frequent after allogeneic HSCT. The factors associated with this infection are type of transplant, pharyngeal colonization, severe mucositis, and use of cephalosporins. Good general conditions and the use of vancomycin were associated with lower risk of enterococcal bacteremia.     

Sirolimus Monotherapy Versus Sirolimus in Combination with Steroids and/or MMF for Immunosuppression After Liver Transplantation

Calcineurin inhibitor (CI)-associated renal dysfunction has emerged as a major cause of morbidity and mortality after liver transplantation. In this retrospective study, we compared the efficacy, safety, and renal protective effect of sirolimus monotherapy (Group A; n=26) with sirolimus in combination (Group B; n=34) with steroids and/or mycophenolate mofetil (MMF) in liver transplant recipients who were switched from CI. Patients were switched abruptly or over a period of 2–4 weeks and followed for 17±10 months. Preconversion renal biopsies in five of six patients showed histological features consistent with CI nephrotoxicity. Serum creatinine increased in the year prior to conversion from 1.7±0.4 to 2.1±0.7 mg/dl (P=0.009) and improved thereafter (1 month, 1.7±0.6, P < 0.001; 6 months, 1.6±0.5, P < 0.001; last follow-up, 1.7±0.9, P=0.02); only four patients showed a significant decline in renal function after conversion. Seven (11.3%) patients experienced acute rejection (Group A, two; Group B, five; P=NS) and this resulted in the discontinuation of sirolimus in one patient. Fifty-four adverse events occurred in 40 (67%) patients, with similar numbers of adverse events in Group A and Group B. Most episodes of rejection (5/7; 71%), adverse events (45/54; 83%), and discontinuations (5/8; 63%) occurred within 6 months of conversion. We conclude that both sirolimus monotherapy and sirolimus in combination with prednisone and/or MMF are efficacious and safe in liver transplant recipients. Conversion to sirolimus was associated with an immediate improvement in renal function that was sustained during the follow-up.     

Evolution of heart rate variability in cardiac transplant recipients: a clinical study

Koskinen P, Virolainen J, Koskinen Pk, Häyry P, Kupari M (Division of Cardiology, Department of Medicine, Helsinki University Central Hospital, and Transplantation Laboratory, University of Helsinki, Helsinki, Finland). Evolution of heart rate variability in cardiac transplant recipients: a clinical study. J Intern Med 1996; 239 : 443–9. Objectives. To investigate in cardiac transplant patients whether post-transplantation time, graft arteriosclerosis, allograft rejection, or earlier cytomegalovirus infection affect the neural regulatory mechanisms of the donor heart. Design. A consecutive series of heart transplant patients during a 12-month period. Setting. A university hospital in Finland. Subjects. Consecutive cardiac transplant recipients (n=38) attending the hospital for their annual clinical examintaion were studied. Their mean (SD) age was 45.4 (11.5) years, 37 were male, and the median (range) time since transplantation was 36 (12–72) months. Interventions. Power spectral analysis of R–R intervals (during 5 min of controlled breathing, the Valsalva manoeuvre, and deep breathing), routine coronary arteriography, cytomegalovirus serology. Results. R–R interval (r=0.67; P<0.001), the root mean square difference of successive R–R intervals (r=0.38; P<0.05), the total R–R interval power (r=0.45; P<0.01), the power of the very low frequency (0.0–0.07 Hz) component (r=0.53; P<0.01), and the power of the nonrespiratory (0.0–0.15 Hz) component (r=0.49; P<0.01) were related to the length of time since the operation. Patients having had a transplantation 3 years ago or more had significantly greater median (range) total R–R interval power than those having had the operation less than 3 years ago (59 [10–265] vs. 20 [3–113] ms²; P=0.02). There was also a difference between the two groups in the very low frequency component (18 [1–226] vs. 5 [0–45] ms²; P=0.01), in the nonrespiratory component (30 [1–227] vs. 9 [0–53] ms²; P=0.02), and in the Valsalva ratio (0.995 [0.955–1.065] vs. 1.020 [0.975–1.155]; P=0.03). Patients with and without graft arteriosclerosis, episodes of rejection, or earlier cytomegalovirus infection showed no difference in the power spectral measures. Conclusions. The donor heart rate variability increases with post-transplantation time. Heart rate variability in transplant recipients is not related to the extent of graft arteriosclerosis, episodes of allograft rejection, or earlier cytomegalovirus infection.     

Differences in the clinical characteristics of Pneumocystis jirovecii pneumonia in immunocompromized patients with and without HIV infection

Background and objective: The incidence of Pneumocystis jirovecii pneumonia (PCP) in patients with predisposing immunodeficiencies other than AIDS is growing. Knowing the different characteristics and outcomes of PCP according to HIV status would help physicians manage and treat patients with PCP. Methods: The medical charts of all patients with a proven first episode of PCP, diagnosed between 1997 and 2007 were retrospectively reviewed, and clinical and laboratory data abstracted. Results: Of the 35 patients with PCP, 18 were HIV‐positive and 17 were HIV‐negative with other immunosuppressive conditions. HIV‐negative patients were significantly older than HIV‐positive patients. The WCC (10 952 ± 5669 vs 9750 ± 3133/µL; P = 0.015), neutrophil counts (9631 ± 5421 vs 5680 ± 2628/µL; P = 0.01) and CD4+ lymphocyte counts (329 ± 502 vs 47 ± 50/µL; P < 0.001) were significantly higher in HIV‐negative patients. Six of the 17 HIV‐negative patients had a CD4+ lymphocyte count >300/µL. Serum IgG levels were lower in HIV‐negative patients (943 ± 379 vs 1635 ± 657 mg/dL; P = 0.017). Mortality was higher in HIV‐negative (52.9%) than in HIV‐positive patients (0%). On univariate analysis, risk factors for mortality from PCP were the presence of underlying pulmonary disease (odds ratio 4.000, 95% CI: 1.501–10.658) and HIV‐negative status (odds ratio 2.125, 95% CI: 1.283–3.518). Conclusions: The characteristics and outcomes of PCP differ significantly depending on HIV status. The existence of underlying pulmonary diseases may be associated with the prognosis of HIV‐negative patients with PCP.     

Pneumocystis jirovecii pneumonia in kidney transplantation

Pneumocystis jirovecii pneumonia (PCP) remains an important cause of morbidity and mortality in immunocompromised renal transplant recipients. In recent years, PCP outbreaks in renal transplant centers have been reported in many countries. Person‐to‐person transmission between PCP patients and other recipients lacking prophylaxis is one of the possible sources of infection. To prevent infection, effective prophylaxis in susceptible patients is recommended. Trimethoprim‐sulfamethoxazole (TMP‐SMX) is the most effective drug for PCP prophylaxis, but its recommended duration of use after transplantation varies among the different guidelines. The European Renal Association recommends a prophylaxis period of 4 months after transplantation, the American Society of Transplantation (AST) 6–12 months, and the Kidney Disease Improving Global Outcomes guidelines 3–6 months. Lifelong prophylaxis with TMP‐SMX is not recommended in renal transplant recipients; however, in many cases, PCP has occurred after the recommended prophylaxis periods after transplantation. In this minireview, we discuss the risk factors including environmental‐nosocomial exposure; state‐of‐the‐art diagnosis, treatment, prophylaxis and isolation; and references to the AST 2009 guidelines with the aim of integrating our experience with PCP outbreaks into recent reports, and we discuss how renal transplant recipients can be protected from PCP.     

Humoral and cellular immune monitoring might be useful to identify liver transplant recipients at risk for development of infection

Abstract: Orthotopic liver transplantation (OLT) is a successful therapy for patients with end‐stage liver disease, and infection remains a significant cause of morbidity and mortality for patients undergoing this procedure. To assess humoral and cellular immunity markers as potential risk factors for development of infection, 46 consecutive liver transplant recipients (hepatitis C virus cirrhosis [n=17], alcoholic liver disease [n=15], hepatocellular carcinoma [n=9], autoimmune hepatitis [n=2], and other [n=3]) performed at a single center were prospectively studied. Maintenance therapy included tacrolimus (n=37) or cyclosporine (n=9) and prednisone. During follow‐up, 27 patients had at least 1 episode of infection (58.7%). Pre‐OLT immunoglobulin G (IgG) hypergammaglobulinemia (relative risk [RR] 2.78; 95% confidence interval [CI], 1.17–6.60, P=0.02), pre‐OLT IgA hypergammaglobulinemia (RR 2.77, CI=1.24–6.19, P=0.012), and pre‐OLT C3 hypocomplementemia (RR 3.02, CI=1.21–7.55, P=0.018) were associated with an increased risk for development of infection. Monitoring of Ig and complement levels might help to identify the risk of developing infection in OLT.     

Analysis of plasma surfactant protein D levels in lung transplant recipients

In lung transplant recipients (LTRs), severe clinical complications, such as microbial infections of the lung or transplant rejection, may occur. Surfactant protein D (SP‐D) is a C‐type lectin that is mainly produced in alveolar type II cells. Plasma SP‐D levels are usually low, but may increase when the lung–blood barrier is impaired. In this study, we analyzed whether plasma SP‐D concentrations reflect rejection or infection of the lung allograft. An enzyme‐linked immunosorbent assay was used to measure SP‐D levels in plasma samples from 58 LTRs during intervals without pathologic respiratory findings and during episodes of acute cellular rejection (ACR), microbial colonization, and microbial pneumonia. Median plasma SP‐D levels were significantly increased during episodes of microbial pneumonia, but not in the absence of pathologic respiratory findings, during microbial colonization, or during ACR up to grade A2–A3 (P < 0.05). During pneumonia, an increased plasma SP‐D level was detected in 60% of LTRs and this was further associated with a significantly higher risk for the patients to develop stage III bronchiolitis obliterans syndrome (BOS III) or to die within the subsequent 6 months after pneumonia (P = 0.0093). All patients with a plasma SP‐D level of >300 ng/mL during pneumonia developed BOS III and/or died within 6 months of follow‐up (P = 0.001). The determination of SP‐D levels in plasma during pneumonia in LTRs may be of prognostic value and warrants further evaluation.     

Risk factors and clinical outcomes of pediatric liver transplant recipients with post‐transplant lymphoproliferative disease in a multi‐ethnic Asian cohort

Background

We aimed to evaluate clinical characteristics, risk factors, and disease outcomes for liver transplant recipients (LTR) with post‐transplant lymphoproliferative disease (PTLD) at our center.

Methods

Retrospective review of data of all pediatric LTR (1991‐2015) was conducted.

Results

The overall incidence of PTLD was 16.4% (18/110), the majority (13/18) were early lesions, while 3/18 were polymorphic/monomorphic PTLD. The risk factors significant on univariate analysis were as follows: mean age (years) at transplant (1.66 vs 4.76, P = .006); age <2 years at transplant (odds ratio [OR] 3.53 [95% confidence interval [CI]: 1.16‐10.73], P = .026); cytomegalovirus (CMV) primary infection (OR 11.39 [95% CI: 3.44‐37.7], P < .001); recipient CMV seronegativity (OR 7.50 [95% CI: 2.02‐27.78], P = .003); presence of CMV end‐organ disease (OR 4.00 [95% CI: 1.22‐13.16], P = .022); Chinese ethnicity; and higher mean duration of intravenous ganciclovir prophylaxis. In multivariate analysis, CMV primary infection (OR 5.22 [95% CI: 1.25‐21.87], P = .024), CMV seronegativity (OR 5.91 [95% CI: 1.13‐30.90, P = .035]), and having acute cellular rejections (ACR) prior to PTLD (OR 5.53 [95% CI: 1.43‐21.48, P = .013]) were significant risk factors for PTLD, with the latter two factors having a synergistic effect in increasing PTLD risk in a stratified analysis. The final multivariate model in predicting the risk of PTLD, utilizing CMV primary infection, recipient CMV seronegativity, and ACR before PTLD as predictive variables, was statistically significant (likelihood ratio chi square statistic = 25.18, P < .0001 with df = 3).

Conclusions

We report a unique clinicopathologic and risk factor profile in our cohort—early lesion PTLD accounts for the majority and the incidence of monomorphic PTLD remains low. In addition, we show a synergism between CMV naivety and ACR on PTLD risk, a higher prevalence of gastrointestinal manifestations, and a lack of significant association with Epstein‐Barr virus seronegativity.     

Predictors of bacterial pneumonia in Evaluation of Subcutaneous Interleukin‐2 in a Randomized International Trial (ESPRIT)

Background and Objectives

Bacterial pneumonia still contributes to morbidity/mortality in HIV infection despite effective combination antiretroviral therapy (cART). Evaluation of Subcutaneous Interleukin‐2 in a Randomized International Trial (ESPRIT), a trial of intermittent recombinant interleukin‐2 (rIL‐2) with cART vs. cART alone (control arm) in HIV‐infected adults with CD4 counts ≥300 cells/μL, offered the opportunity to explore associations between bacterial pneumonia and rIL‐2, a cytokine that increases the risk of some bacterial infections.

Methods

Baseline and time‐updated factors associated with first‐episode pneumonia on study were analysed using multivariate proportional hazards regression models. Information on smoking/pneumococcal vaccination history was not collected.

Results

IL‐2 cycling was most intense in years 1–2. Over ≈7 years, 93 IL‐2 [rate 0.67/100 person‐years (PY)] and 86 control (rate 0.63/100 PY) patients experienced a pneumonia event [hazard ratio (HR) 1.06; 95% confidence interval (CI) 0.79, 1.42; P=0.68]. Median CD4 counts prior to pneumonia were 570 cells/μL (IL‐2 arm) and 463 cells/μL (control arm). Baseline risks for bacterial pneumonia included older age, injecting drug use, detectable HIV viral load (VL) and previous recurrent pneumonia; Asian ethnicity was associated with decreased risk. Higher proximal VL (HR for 1 log₁₀ higher VL 1.28; 95% CI 1.11, 1.47; P<0.001) was associated with increased risk; higher CD4 count prior to the event (HR per 100 cells/μL higher 0.94; 95% CI 0.89, 1.0; P=0.04) decreased risk. Compared with controls, the hazard for a pneumonia event was higher if rIL‐2 was received <180 days previously (HR 1.66; 95% CI 1.07, 2.60; P=0.02) vs.≥180 days previously (HR 0.98; 95% CI 0.70, 1.37; P=0.9). Compared with the control group, pneumonia risk in the IL‐2 arm decreased over time, with HRs of 1.41, 1.71, 1.16, 0.62 and 0.84 in years 1, 2, 3–4, 5–6 and 7, respectively.

Conclusions

Bacterial pneumonia rates in cART‐treated adults with moderate immunodeficiency are high. The mechanism of the association between bacterial pneumonia and recent IL‐2 receipt and/or detectable HIV viraemia warrants further exploration.     

Hospitalized poisonings after renal transplantation in the United States

Background

The national incidence of and risk factors for hospitalized poisonings in renal transplant recipients has not been reported.

Methods

Historical cohort study of 39,628 renal transplant recipients in the United States Renal Data System between 1 July 1994 and 30 June 1998. Associations with time to hospitalizations for a primary diagnosis of poisonings (ICD-9 codes 960.x-989.x) within three years after renal transplant were assessed by Cox Regression.

Results

The incidence of hospitalized poisonings was 2.3 patients per 1000 person years. The most frequent causes of poisonings were immunosuppressive agents (25.3%), analgesics/antipyretics (14.1%), psychotropic agents (10.0%), and insulin/antidiabetic agents (7.1%). In Cox Regression analysis, low body mass index (BMI, <21.6 vs. >28.3 kg/m², adjusted hazard ratio (AHR), 3.02, 95% CI, 1.45–6.28, and allograft rejection, AHR 1.83, 95% CI, 1.15–2.89, were the only factors independently associated with hospitalized poisonings. Hospitalized poisonings were independently associated with increased mortality (AHR, 1.54, 95% CI 1.22–1.92, p = 0.002).

Conclusions

Hospitalized poisonings were associated with increased mortality after renal transplantation. However, almost all reported poisonings in renal transplant recipients were due to the use of prescribed medications. Allograft rejection and low BMI were the only independent risk factors for poisonings identified in this population.     

Choice of induction regimens on the risk of cytomegalovirus infection in donor‐positive and recipient‐negative kidney transplant recipients

F.L. Luan, M. Samaniego, M. Kommareddi, J.M. Park, A.O. Ojo. Choice of induction regimens on the risk of cytomegalovirus infection in donor‐positive and recipient‐negative kidney transplant recipients.
Transpl Infect Dis 2010: 12: 473–479. All rights reserved Background. Late occurrence of cytomegalovirus (CMV) infection remains a concern in CMV‐seronegative kidney and/or pancreas transplant recipients of CMV‐seropositive organs (donor positive/recipient negative, D+/R?) despite the use of prophylaxis. We investigated the impact of various antibody induction regimens on CMV infection in this group of patients. Methods. A total of 254 consecutive D+/R? kidney and/or pancreas transplant patients were studied. The induction agents rabbit anti‐thymocyte globulin (rATG) or basiliximab were used according to the center practice. All patients received prophylaxis with valganciclovir (VGCV) for either 3 or 6 months. The occurrence of CMV infection was confirmed by positive DNA viremia. Multivariate Cox regression analyses were performed to determine risk factors for CMV infection. Results. The cumulative incidence of CMV infection was 58, 112, and 59 cases per 1000 patient‐years for patients who received no antibody induction, induction with rATG, or basiliximab induction, respectively (P=0.02). The use of rATG but not basiliximab was associated with an increased risk for CMV infection (adjusted hazard ratio [AHR] 2.13, 95% confidence interval [CI] 1.24–3.54, P=0.006). Acute rejection and its treatment with rATG were not associated with an increased risk for CMV infection when an additional course of VGCV was given following the treatment. Longer duration of prophylaxis was associated with a reduced risk for CMV infection (AHR 0.54, 95% CI 0.33–0.87, P=0.011). Conclusions. Induction with rATG is associated with increased risk of CMV infection. Longer duration of prophylaxis is beneficial.     

Trends and Outcomes of Left Atrial Appendage Occlusion in Renal and Liver Transplant Recipients: Insights From the United States National Inpatient and Readmission Database

Left atrial appendage occlusion using the Watchman device has emerged as an alternative treatment strategy for preventing strokes in patients with atrial fibrillation. However, there is no data on its safety and clinical outcomes in prior renal or liver transplant recipients. We included a total of 61,995 patients from the National Inpatient Sample (NIS, in-hospital outcomes) and 55,048 patients from the National Readmission Database (NRD, 30-day outcomes) who underwent percutaneous left atrial appendage occlusion (LAAO). From this group, 0.65% (n=405) and 0.62% (n=339) were renal and liver transplant recipients in NIS and NRD respectively. Transplant recipients were younger compared with non-transplant recipients (mean age 69 vs 77 years, P=<0.01). There was little difference in terms of in-hospital mortality (0% vs 0.2%, P=0.43), major complications (6.2% vs 5.6%, P=0.61), cardiovascular complications (2.5% vs 2.8%, P=0.73), neurological complications (1.2% vs 0.7%, P=0.21) or bleeding complications (1.2% vs 0.7%, P=0.99) between transplant vs. non-transplant patients. Based on the NRD database, 30-day readmission rate was not meaningfully different for transplant recipients undergoing LAAO (9.44%) when compared to non-transplant patients (8.12%, [log-rank, P=0.56]). There was no difference between 30-day major or cardiovascular complications, however vascular complication rates were significantly higher for transplant recipients (OR 2.56, 95% CI [(1.66-3.47]). Our study findings suggest that LAAO may be safe for patients with a prior renal or liver transplant in terms of major complications, cardiovascular complications, and all-cause readmission rates. However vascular complications may be higher in transplant recipients. Further large-scale studies are needed to confirm these findings.     

Transplantation related toxicity and mortality in older autologous hematopoietic cell transplantation recipients

With advances in supportive care, autologous hematopoietic cell transplant (AHCT) is increasingly being performed for patients older than 60 years. We analyzed patients receiving an AHCT for multiple myeloma or lymphoma in a contemporary cohort (2010–2012), with consistent treatment and supportive care and compared outcomes [CTCAE grade 3–5 toxicities, nonrelapse mortality (NRM) and overall‐survival (OS)] of younger (40–59 years, n = 77) versus older (≥60 years, n = 67) recipients. The proportion of patients with neutropenic infections was higher in the older group (64% vs. 44%; P = 0.02). The proportion of patients with any grade 3–5 toxicity was also higher in the older group (84% vs. 67%, P = 0.03). In multivariate analysis, older age was significantly associated with higher odds (OR: 2.57, 95% CI:1.09–6.05) of grade 3–5 toxicity. The NRM was 3% (older) vs. 0% (younger) at 1 year. The probability of OS at 2 years was lower in the older group (76% vs. 90%, P = 0.04). Though AHCT can be performed safely in older recipients, the higher toxicity and slightly higher NRM in this population needs attention. Studies focusing on risk‐stratification in older patients would further help predict toxicity. Further studies addressing enhanced supportive care needs for older patients who are most likely to benefit are indicated.     

Trends in invasive disease due to Candida species following heart and lung transplantation

Abstract: Although invasive candidiasis (IC) causes significant morbidity and mortality in patients who undergo heart, lung, or heart–lung transplantation, a systematic study in a large cohort of thoracic organ transplant recipients has not been reported to date. Clinical and microbiological data were reviewed for 1305 patients who underwent thoracic organ transplantation at Stanford University Medical Center between 1980 and 2004. We identified and analyzed 76 episodes of IC in 68 patients (overall incidence 5.2% per patient). The incidence of IC was higher in lung (LTx) and heart–lung transplant (HLTx) recipients as compared with heart transplant (HTx) recipients (risk ratio [RR] 1.7, 95% confidence interval [CI] 1.1–2.7). The incidence of IC decreased over time in all thoracic organ transplant recipients, decreasing from 6.1% in the 1980–1986 time period to 2.1% in the 2001–2004 era in the HTx recipients, and from 20% in the 1980–1986 period to 1.8% in the 2001–2004 period in the LTx and HLTx recipients. The most common site of infection differed between the HTx and LTx cohorts, with bloodstream or disseminated disease in the former and tracheobronchitis in the latter. IC in the first year after transplant was significantly associated with death in both HTx (RR 2.9, 95% CI 1.8–4.6, P=0.001) and LTx and HLTx patients (RR 3.0, 95% CI 1.9–4.6, P<0.001). The attributable mortality from IC decreased during the 25‐year period of observation, from 36% to 20% in the HTx recipients and from 39% to 15% in the LTx and HLTx recipients. There were a significant number of cases caused by non‐albicans Candida species in all patients, with a trend toward higher mortality in the HTx group. In conclusion, the incidence and attributable mortality of IC in thoracic organ transplant recipients has significantly declined over the past 25 years. The use of newer antifungal agents for prophylaxis and treatment, the decrease in the incidence of cytomegalovirus disease, and the use of more selective immunosuppression, among other factors, may have been responsible for this change.     

Intravenous immunoglobulin as adjunctive therapy in kidney transplant recipients with severe pneumocystis pneumonia

Pneumocystis jirovecii is an opportunistic pathogen that may cause severe, life‐threatening respiratory infections in immunocompromised patients such as those with kidney transplants. Although antimicrobial prophylaxis is now universally recommended in the early post‐transplant period, Pneumocystis pneumonia (PCP) can occur later. If such infection occurs, mortality rates are high. Beyond standard therapy with trimethoprim‐sulfamethoxazole, there is a lack of evidence‐based options for intensifying treatment when initial therapy fails to show improvement. Moreover, it is usual to minimize immunosuppression in life‐threatening infection, but graft damage may occur, particularly in kidney transplant recipients at above‐average immunological risk. Here we present two cases of severe PCP in high immunological risk recipients who were managed with adjunctive intravenous immunoglobulin and withdrawal of immunosuppression. Both patients recovered and were discharged from hospital with functioning grafts.     

Retrospective case analysis of antiviral therapies for HHV‐6 encephalitis after hematopoietic stem cell transplantation

Human herpesvirus 6 (HHV‐6) is one of the most common causes of encephalitis in allogeneic hematopoietic stem cell transplant (HCT) recipients and is associated with significant morbidity and mortality. There are no FDA‐approved treatments specifically for HHV‐6 encephalitis; HHV‐6 disease is typically treated with CMV antivirals. A review of antiviral medications used to treat HHV‐6 encephalitis was conducted by aggregating data from case reports found on PubMed. Articles were included if they examined at least one HCT patient diagnosed with HHV‐6 encephalitis and described their treatment course and outcome. Key data were abstracted from 123 cases described in 52 studies. The proportion of patients with encephalitis who died or developed sequelae was 63.6% among ganciclovir monotherapy recipients (n = 44), 55.3% among foscarnet monotherapy recipients (n = 47), and 37.5% among recipients of combination therapy with foscarnet and ganciclovir (n = 32). Logistic regression revealed that recipients of foscarnet (OR 4.286, 95% CI 1.235‐14.877, P = .022) and ganciclovir (OR 5.625, 95% CI 1.584‐19.975, P = .008) monotherapies were more likely to develop sequelae compared to recipients of combination therapy, respectively. In multivariate analyses, non‐cord blood transplant was identified as an independent risk factor for developing sequelae after receiving ganciclovir monotherapy (OR 5.999, 95% CI 1.274‐28.254, P = .023). There was no difference in mortality between patients who received combination therapy and those who received monotherapy. In conclusion, combination therapy with foscarnet and ganciclovir may reduce sequelae, but not mortality, secondary to HHV‐6 encephalitis.