Bloodstream infections in organ transplant recipients receiving alemtuzumab: no evidence of occurrence of organisms typically associated with profound T cell depletion

Risk of Staphylococcus aureus Bacteremia Before and After Solid Organ Transplantation

BACKGROUND

Solid organ transplant recipients are at high risk for Staphylococcus aureus bacteremia, but the risks before and after transplantation require further research.

METHODS

We performed a population-based retrospective self-controlled study using the State Inpatient Database from 10 states in the United States. Adult and pediatric patients who had solid organ transplantation from 2004 to 2018 were tracked longitudinally for 1 y before and after transplantation outside of the immediate peritransplant periods. The exposure of interest was solid organ transplantation, and the outcome of interest was hospitalization with S. aureus bacteremia.

RESULTS

Of 75 549 patients, 581 (0.77%) and 239 (0.32%) were hospitalized with S. aureus bacteremia in the pretransplant and posttransplant periods, respectively ( P < 0.001). Overall, the odds of hospitalization with S. aureus bacteremia increased from 7 to 12 mo to 1 to 6 mo before transplantation (odds ratio, 1.24; 95% confidence interval, 1.05-1.46) and then decreased following transplantation (odds ratio, 0.35; 95% confidence interval, 0.28-0.45; 7-12 mo after transplantation). The decreased rate after transplantation was driven by the cases associated with central line-associated bloodstream infections and endocarditis among kidney and heart transplant recipients. Odds of hospitalization with S. aureus bacteremia did not change after liver transplantation, whereas they increased after lung transplantation.

CONCLUSIONS

In addition to immunosuppression, the reversal of organ failure and associated requirements for organ support following transplantation may play an important role in the risk of S. aureus bacteremia in solid organ transplant recipients. These results can guide infection prevention approaches and future research on S. aureus infections in transplant patients.

Outcomes with alemtuzumab induction therapy in lung transplantation: a comprehensive large-scale single-center analysis

Alemtuzumab is a monoclonal antibody targeting CD52, increasingly used as induction therapy after transplantation. The aim of this study was to analyze the outcomes of alemtuzumab induction therapy followed by a low-dose maintenance immunosuppression in a large single-center cohort of lung transplant recipients. All patients, who received alemtuzumab induction followed by a low-dose maintenance immunosuppression were included in the analysis. Short- and long-term outcomes were analyzed. 721 lung transplant recipients, transplanted between January 2008 and June 2019, were included in this retrospective study. Freedom from higher-grade ACR at 1, 5, and 10 years was 98%, 96%, and 96%, respectively. Thirty-nine patients (5%) developed clinical AMR. Twenty-one percent of patients developed high-grade CKD. A total of 1488 infections were recorded. Sixteen percent were diagnosed within the first 3 months. Sixty-two patients (9%) developed a malignancy during follow-up. Freedom from CLAD at 1, 5, and 10 years was 94%, 72%, and 53%, respectively. Overall survival rates at 1, 5, and 10 years were 85%, 71%, and 61%, respectively. Alemtuzumab induction combined with a low-dose tacrolimus protocol is safe and associated with low rates of acute and chronic rejection, as well as an excellent long-term survival.

Challenges in the Diagnosis and Management of Bacterial Lung Infections in Solid Organ Recipients: A Narrative Review

Respiratory infections pose a significant threat to the success of solid organ transplantation, and the diagnosis and management of these infections are challenging. The current narrative review addressed some of these challenges, based on evidence from the literature published in the last 20 years. Specifically, we focused our attention on (i) the obstacles to an etiologic diagnosis of respiratory infections among solid organ transplant recipients, (ii) the management of bacterial respiratory infections in an era characterized by increased antimicrobial resistance, and (iii) the development of antimicrobial stewardship programs dedicated to solid organ transplant recipients.

Alemtuzumab induction combined with reduced maintenance immunosuppression is associated with improved outcomes after lung transplantation: A single centre experience

Question addressed by the study

The value of induction therapy in lung transplantation is controversial. According to the ISHLT, only about 50% of patients transplanted within the last 10 years received induction therapy. We reviewed our institutional experience to investigate the impact of induction therapy on short- and long-term outcomes.

Materials/Patients and methods

Between 2007 and 2015, 446 patients with a complete follow-up were included in this retrospective analysis. Analysis comprised long-term kidney function, infectious complications, incidence of rejection and overall survival.

Results

A total of 231 patients received alemtuzumab, 50 patients antithymocyte globulin (ATG) and 165 patients did not receive induction therapy (NI). The alemtuzumab group revealed the lowest rate of chronic kidney insufficiency (NI: 52.2%; ATG: 60%; alemtuzumab: 36.6%; p = 0.001). Both, the NI group (p<0.001) and the ATG group (p = 0.010) showed a significant increase of serum creatinine during follow-up compared to alemtuzumab patients. Furthermore, alemtuzumab group experienced the lowest rate of infection in the first year after transplantation. Finally, improved survival, low rates of acute cellular rejection (ACR), lymphocytic bronchiolitis (LB) and chronic lung allograft dysfunction (CLAD) were found in patients treated either with alemtuzumab or ATG.

Conclusion

Alemtuzumab induction therapy followed by reduced maintenance immunosuppression is associated with a better kidney function compared to no induction and ATG. Survival rate as well as freedom from ACR and CLAD were comparable between alemtuzumab and ATG.

Incidence of invasive pneumococcal disease in immunocompromised patients: A systematic review and meta-analysis

BACKGROUND

Invasive pneumococcal disease (IPD) is associated with high morbidity and mortality, with immunocompromised patients (ICPs) at particular risk. Therefore, guidelines recommend pneumococcal vaccination for these patients. However, guidelines are scarcely underpinned with references to incidence studies of IPD in this population. This, potentially results in unawareness of the importance of vaccination and low vaccination rates. The objective of this systematic review and meta-analysis was to assess the incidence of IPD in ICPs.

METHODS

We systematically searched PubMed and Embase to identify studies in English published before December 6th, 2017 that included terms related to 'incidence', 'rate', 'pneumococcal', 'pneumoniae', 'meningitis', 'septicemia', or 'bacteremia'. We focused on patients with HIV, transplantation and chronic inflammatory diseases.

RESULTS

We included 45 studies in the systematic review reporting an incidence or rate of IPD, defined as isolation of Streptococcus pneumoniae from a normally sterile site. Random effects meta-analysis of 38 studies showed a pooled IPD incidence of 331/100,000 person years in patients with HIV in the late-antiretroviral treatment era in non-African countries, and 318/100,000 in African countries; 696 and 812/100,000 in patients who underwent an autologous or allogeneic stem cell transplantation, respectively; 465/100,000 in patients with a solid organ transplantation; and 65/100,000 in patients with chronic inflammatory diseases. In healthy control cohorts, the pooled incidence was 10/100,000.

DISCUSSION

ICPs are at increased risk of contracting IPD, especially those with HIV, and those who underwent transplantation. Based on our findings, we recommend pneumococcal vaccination in immunocompromised patients.

PROSPERO REGISTRATION

ID: CRD42016048438.

The Impact of Alemtuzumab and Basiliximab Induction on Patient Survival and Time to Bronchiolitis Obliterans Syndrome in Double Lung Transplantation Recipients

We examined the effect of alemtuzumab and basiliximab induction therapy on patient survival and freedom from bronchiolitis obliterans syndrome (BOS) in double lung transplantation. The United Network for Organ Sharing database was reviewed for adult double lung transplant recipients from 2006 to 2013. The primary outcome was risk-adjusted all-cause mortality. Secondary outcomes included time to BOS. There were 6117 patients were identified, of whom 738 received alemtuzumab, 2804 received basiliximab, and 2575 received no induction. Alemtuzumab recipients had higher lung allocation scores compared with basiliximab and no-induction recipients (41.4 versus 37.9 versus 40.7, p < 0.001) and were more likely to require mechanical ventilation before to transplantation (21.7% versus 6.5% versus 6.2%, p < 0.001). Median survival was longer for alemtuzumab and basiliximab recipients compared with patients who received no induction (2321 versus 2352 versus 1967 days, p = 0.001). Alemtuzumab (hazard ratio 0.80, 95% confidence interval 0.67-0.95, p = 0.009) and basiliximab induction (0.88, 0.80-0.98, p = 0.015) were independently associated with survival on multivariate analysis. At 5 years, alemtuzumab recipients had a lower incidence of BOS (22.7% versus 55.4 versus 55.9%), and its use was independently associated with lower risk of developing BOS on multivariate analysis. While both induction therapies were associated with improved survival, patients who received alemtuzumab had greater median freedom from BOS.

The Distribution and Resistance of Pathogens Among Solid Organ Transplant Recipients with Pseudomonas aeruginosa Infections

Background

Pseudomonas aeruginosa infection remains a life-threatening complication after solid organ transplantation (SOT). We aimed to investigate the distribution and drug susceptibility of pathogens, and clinical characteristics of SOT recipients with Pseudomonas aeruginosa infections.

Material/Methods

A total of 55 SOT recipients who developed 61 episodes of Pseudomonas aeruginosa infections between January 1, 2003 and July 31, 2015 were retrospectively analyzed. The distribution and the drug susceptibility of Pseudomonas aeruginosa were reviewed.

Results

The most common site from which 61 Pseudomonas aeruginosa rods were isolated were the lungs (57.4%, n=37), followed by the blood (27.9%, n=17). There were 35, 18, and 9 recipients accompanied with a serum creatinine level of >1.5 mg/dL, lymphocyte count of <300/mm³, and a serum albumin level of <30 g/L, respectively. Seven patients each presented with white blood cell count of >15 000/mm³ and platelet count of <50 000/mm³. There were 6 (10.9%) cases of septic shocks and 18 (32.7%) deaths. Antibiotic resistance rate of all Pseudomonas aeruginosa to 4 of 10 antibiotics investigated was more than 50%. Of these 61 Pseudomonas aeruginosa isolates, 47.5% were carbapenem-resistant. The rods were relatively sensitive to piperacillin-tazobactam, levofloxacin, amikacin, and cefoperazone-sulbactam (resistance rate <40%).

Conclusions

The clinical presentation of Pseudomonas aeruginosa infections included high body temperature, decreased platelet count, elevated white blood cell count, a high nosocomial origin and mortality, and onset in the late period after transplantation. According to our findings, piperacillin-tazobactam, levofloxacin, amikacin, and cefoperazone-sulbactam, alone or combination, are recommended to treat SOT recipients with Pseudomonas aeruginosa infections.

Predictors of shock and mortality in solid organ transplant recipients with bacteremia caused by non-lactose-fermenting gram-negative bacilli

BACKGROUND

More data on bacteremia due to non-lactose fermenting gram-negative bacilli (NLF GNB) in solid organ transplant (SOT) recipients are needed. We aimed to investigate the epidemiology, microbiology, and risk factors for mortality and septic shock due to NLF GNB bacteremia in SOT recipients.

METHODS

We performed a retrospective, double-center study over a 12-year study period. The risk factors for mortality and septic shock in SOT recipients with NLF GNB bacteremia were assessed with multivariate logistic regression analysis.

RESULTS

A total of 230 episodes of bloodstream infections (BSIs) occurred in 159 SOT recipients. Fifty episodes of NLF GNB bacteremia were detected in 47 SOT recipients, with a predominance of Acinetobacter baumanii (27 isolates, 54.0%). The antibiotic resistance rate of all NLF GNB to 10 of 12 antibiotics investigated was more than 50%. The independent risk factors associated with septic shock were platelet count < 50 000/mm(3) (odds ratio (OR) = 14.41, 95% confidence interval (CI) = 2.64-78.71, p = 0.002) and late-onset bacteremia (time of onset more than 2 months post-transplant) (OR = 10.87, 95% CI = 1.79-65.89, p = 0.009). Lung focus (OR = 32.91, 95% CI = 2.56-423.18, p = 0.007) and septic shock (OR = 70.38, 95% CI = 4.21-1176.21, p = 0.003) were risk factors for bacteremia-related mortality.

CONCLUSIONS

The drug resistance of the pathogens and the morbidity and mortality rates of NLF GNB bacteremia were high in SOT recipients. For septic shock, associated risk factors were thrombocytopenia and late-onset bacteremia. The risk factors significantly associated with mortality were lung focus and septic shock.

The Bacteremia Caused by Non-Lactose Fermenting Gram-Negative Bacilli in Solid Organ Transplant Recipients

BACKGROUND

Blood stream infections (BSIs) remain as a serious life-threatening condition after solid organ transplant (SOT). In recent years, a progressive growth in the incidence of bacteremia caused by non-lactose fermenting gram-negative bacilli (NLF GNB) has been observed. NLF GNB led to high mortality among SOT recipients with bacteremia and were difficult to treat because of their high drug resistance to commonly used antibiotics.

METHODS

Two electronic databases, PUBMED and EMBASE, were searched for relevant literature published up to January 2015, to better understand the characteristics of bacteremia because of NLF GNB.

RESULTS

The morbidity and mortality rates of bacteremia because of NLF GNB depend on the types of organisms and transplantation. Multi-drug resistant NLF GNB ranged from 9.8% to 12.5% of all NLF GNB causing BSIs among SOT recipients. Certain factors can predispose SOT recipients to NLF GNB bacteremia, which included previous transplantation, hospital-acquired BSIs, and prior intensive care unit admission. Combination therapy may be beneficial in the treatment of NLF GNB bacteremia to enhance antimicrobial activity, provide synergistic interactions, relieve side effects, and minimize superinfections.

CONCLUSIONS

Prevention is pivotal in minimizing the morbidity and mortality associated with NLF GNB bacteremia after SOT. To improve the outcomes of SOT recipients with NLF GNB bacteremia, prevention is pivotal, and combination therapy of antibiotics may be beneficial.

Multidrug-resistant Gram-negative bacteria in solid organ transplant recipients with bacteremias

Bloodstream infections (BSIs) remain as life-threatening complications and are associated with significant morbidity and mortality among solid organ transplant (SOT) recipients. Multidrug-resistant (MDR) Gram-negative bacteria can cause serious bacteremias in these recipients. Reviews have aimed to investigate MDR Gram-negative bacteremias; however, they were lacking in SOT recipients in the past. To better understand the characteristics of bacteremias due to MDR Gram-negative bacteria, optimize preventive and therapeutic strategies, and improve the outcomes of SOT recipients, this review summarize the epidemiology, clinical and laboratory characteristics, and explores the mechanisms, prevention, and treatment of MDR Gram-negative bacteria.

Bloodstream infections among solid organ transplant recipients: Epidemiology, microbiology, associated risk factors for morbility and mortality

Bloodstream infections (BSIs) remain important causes of morbidity and mortality among solid organ transplant (SOT) recipients and still threaten the success of SOT. In general, among SOT recipients, risk factors for BSIs are associated with prior ICU admission, catheterization, older recipient or donor age…etc. Pulmonary focus, nosocomial source of BSIs, lack of appropriate antibiotic therapy and other variables have significant impacts on BSIs-related mortality in SOT. Most of BSIs in SOT are caused by gram-negative bacteria. However, all aspects including microbiological spectrum, morbidity and mortality rates, risk factors of BSIs and BSIs-related death depend on the type of transplantation. The purpose of this review is to summarize the epidemiology, microbiologic features including antimicrobial resistance of organisms, and associated risk factors for morbidity and mortality of BSIs according to different type of transplantation to better understand the characteristics of BSIs and improve the outcomes after SOT.

Approaching the promise of operational tolerance in clinical transplantation

Long-term acceptance of transplanted organs without requirement for indefinite immunosuppression remains the ultimate goal of transplant clinicians and scientists. This clinical state of allograft acceptance termed "operational tolerance" has been elusive in routine practice. However, there are published reports of recipients where immunosuppression has been discontinued, by intention or patient noncompliance, in which the outcome is a nondestructive immune response and normal function. The question now arises how clinical operational tolerance might be achieved in the majority of recipients. This review provides an overview of current approaches to achieve operational tolerance, including the use of donor bone marrow and depletion of recipient T cells and the resistance of liver transplants to rejection. It also describes the key role of clinical immune monitoring and future approaches to tolerance induction including inhibition of T-cell signaling, manipulation of costimulatory pathways, and expansion of regulatory T cells. The principles of these experimental approaches may ultimately be extended to provide safe and effective control of transplant rejection and induction of clinical operational tolerance.

Five-year outcomes with alemtuzumab induction after lung transplantation

BACKGROUND

Induction therapy with alemtuzumab, followed by lower than conventional intensity post-transplant immunosuppression (eg, tacrolimus monotherapy), has been associated with reduced morbidity and mortality in abdominal and heart transplantation. We examined 5-year outcomes in lung recipients receiving alemtuzumab in conjunction with reduced-intensity post-transplant immunosuppression (early lower-dose tacrolimus; lower-dose steroids, with or without mycophenolate mofetil), compared with lung recipients receiving other induction agents or no induction in association with post-transplant immunosuppression.

METHODS

A retrospective analysis was performed using prospectively collected data from a single-site clinical database of 336 lung recipients (aged ≥ 18) who received allografts between 1998 and 2005, classified by induction type: alemtuzumab, 127; Thymoglobulin, 43; daclizumab, 73; and none, 93. Survival analyses examined patient and graft survival, and freedom from acute cellular rejection (ACR), lymphocytic bronchiolitis, obliterative bronchiolitis (OB), bronchiolitis obliterans syndrome (BOS), and post-transplant lymphoproliferative disorder (PTLD).

RESULTS

Five-year patient and graft survival differed by group (p = 0.046, p = 0.038, respectively). Alemtuzumab patient/graft survival rates were 59%/59%. Survival rates were 60%/44% for Thymoglobulin, 47%/46% for no induction, and 44%/41% for daclizumab. Freedom from ACR, lymphocytic bronchiolitis, OB, and BOS differed by group (all values, p < 0.008); alemtuzumab recipients showed greater 5-year freedom from each outcome (30%/82%/86%/54%) than Thymoglobulin (20%/54%/62%/27%), daclizumab (19%/55%/70%/43%), and no-induction groups (18%/70%/69%/46%). The groups did not differ in PTLD rates (≥ 94% free of PTLD at 5 years; p = 0.864). Effects were unchanged after controlling for potential covariates.

CONCLUSIONS

Alemtuzumab induction may be associated with improved outcomes in lung transplantation. Randomized controlled trials are needed to establish any effects of this agent.

Alemtuzumab in solid organ transplantation and in composite tissue allotransplantation

Alemtuzumab (Campath®, Genzyme Corporation, MA, USA) is a potent monoclonal antilymphocyte, anti-CD52 antibody. Since the 1980s, alemtuzumab has been used extensively in organ transplantation as an induction agent – also with the aim of avoiding or reducing maintenance immunosuppression. We herein review the literature on alemtuzumab in solid organ and composite tissue allotransplantation with an emphasis on clinical and mechanistic aspects of alemtuzumab. In summary, the use of alemtuzumab in solid organ and composite tissue allotransplantation shows excellent early results and holds potential for wider use in conjunction with immunosuppression minimization protocols.

Bloodstream infection after kidney transplantation: epidemiology, microbiology, associated risk factors, and outcome

BACKGROUND

Bloodstream infection (BSI) is associated with both relevant morbidity and mortality rates after kidney transplantation.

METHODS

From January 1, 2000 to January 31, 2006, all episodes of BSI were retrospectively assessed through the review of medical records in two tertiary teaching Hospitals in Sao Paulo, Brazil, where 3308 transplant procedures were performed during this period. Contaminants and polymicrobial infections were excluded. The main objectives of the study were to describe clinical and microbiologic aspects of BSI, as well as risk factors for both BSI and mortality from these infections in kidney transplant patients.

RESULTS

BSI was detected in 185 patients, with onset after a median of 235 days after transplantation; 62% occurred after 6 months. The primary source of infection was the urinary tract in 37.8%. The most prevalent pathogen overall was Escherichia coli (30.3%). Risk factors for early acquired BSI (first 6 months after transplantation) were acute rejection, ureteric stent placement, and receiving an organ from a deceased donor. For late BSI (after 6 months), associated risk factors were acute rejection, Charlson Comorbidity Score more than or equal to 3, and receiving an organ from a deceased donor. Risk factors related to 30-day mortality were Acute Physiology and Chronic Health Evaluation II Score more than or equal to 20, shock, and respiratory failure.

CONCLUSIONS

BSI is most frequently a consequence of urinary tract infection, with a high prevalence of gram-negative bacilli. Severity of disease was the main determinant of 30-day mortality after BSI, and based on the knowledge of risk factors, some interventions are suggested for reducing the rate of BSI after transplantation.

Alemtuzumab and liver transplantation: a review

PURPOSE OF REVIEW

Liver transplantation has always been fraught with conflict. The ongoing shortage of organs for transplantation has led to sicker recipients and the pressure to utilize more marginal grafts. At the same time, increasing public scrutiny and regulatory oversight have emphasized lower costs and better outcomes. This environment exaggerates the importance of the most fundamental conflict: that between preventing allograft rejection and avoiding the toxicities of immunosuppressive agents and the risks of infection. Resolving this struggle requires skillful balancing and a need to keep abreast of the latest developments. Alemtuzumab is a still-new agent with relatively little clinical experience that, therefore, deserves a review and an update of current knowledge in the setting of liver transplantation.

RECENT FINDINGS

The use of alemtuzumab in liver transplant recipients has shown promise with little information to support concerns over significantly increased risks of infectious complications. However, there have been very few studies overall and fewer still in the last 2-3 years. Much of what is known must still be extrapolated from experience in kidney transplant recipients.

SUMMARY

Alemtuzumab appears to be a drug with significant potential advantages for liver transplant recipients. Improved renal function may be the largest potential advantage. However, the advantages may be offset in some groups. Defining subgroups will be critical to the definition of the optimal role of alemtuzumab in liver transplant recipients.

Impact of induction therapy on bacterial infections and long-term outcome in adult intestinal and multivisceral transplantation: a comparison of two different induction protocols: daclizumab vs. alemtuzumab

INTRODUCTION

Induction therapy with daclizumab or alemtuzumab has been recently introduced for intestinal transplantation; however, the impact of such induction therapy on bacterial infections remains to be clarified. The purpose of this study was to evaluate the impact of induction therapy on the incidence of bacterial infections and long-term patient survival.

PATIENTS AND METHODS

Over the past seven yr, we performed 39 intestinal (ITx) and multivisceral (MTVx) transplants in 38 adult patients. In the early period, daclizumab was used for induction, and tacrolimus and steroids were administered for maintenance [daclizumab and tacrolimus (DT) group; n = 11]. From 2002, we used alemtuzumab for induction, with low-dose tacrolimus maintenance [alemtuzumab and tacrolimus (AT) group; n = 23]. The incidence of bacterial infections and patient outcome were compared between the two groups.

RESULTS

There were no significant differences in recipient and donor demographics, procedure (ITx vs. MTVx), and cold and warm ischemic time between the two groups. Within 30 d after ITx, bacterial infections were observed in seven patients (64%) in the DT and in 14 patients (64%) in the AT group. Between 30 and 180 d after ITx, a total of 17 episodes of bacterial infections were observed in the DT and 26 episodes in the AT group. Three patients in the DT and eight in the AT group died, and all of the deaths were related to infectious complications except one each in DT and AT.

CONCLUSION

There was no difference in incidence of bacterial infections and long-term patient survival between the two groups.

Invasive aspergillosis: epidemiology, diagnosis and management in immunocompromised patients

Morbidity and mortality caused by invasive Aspergillus infections are increasing. This is because of the higher number of patients with malignancies treated with intensive immunosuppressive therapy regimens as well as their improved survival from formerly fatal bacterial infections, and the rising number of patients undergoing allogeneic haematopoietic stem cell or organ transplantation. Early initiation of effective systemic antifungal treatment is essential for a successful clinical outcome in these patients; however, clinical clues for diagnosis are sparse and early microbiological proof of invasive aspergillosis (IA) is rare. Clinical diagnosis is based on pulmonary CT scan findings and non-culture based diagnostic techniques such as galactomannan or DNA detection in blood or bronchoalveolar lavage samples. Most promising outcomes can be expected in patients at high risk for aspergillosis in whom antifungal treatment has been started pre-emptively, backed up by laboratory and imaging findings. The gold standard of systemic antifungal treatment is voriconazole, which has been proven to be significantly superior to conventional amphotericin B and has led to a profound improvement of survival rates in patients with cerebral aspergillosis. Liposomal amphotericin B at standard dosages appears to be a suitable alternative for primary treatment, while caspofungin, amphotericin B lipid complex or posaconazole have shown partial or complete response in patients who had been refractory to or intolerant of primary antifungal therapy. Combination therapy with two antifungal compounds may be a promising future strategy for first-line treatment. Lung resection helps to prevent fatal haemorrhage in single patients with pulmonary lesions located in close proximity to larger blood vessels, but is primarily considered for reducing the risk of relapse during subsequent periods of severe immunosuppression. Strict reverse isolation appears to reduce the incidence of aspergillosis in allogeneic stem cell transplant recipients and patients with acute myeloid leukaemia undergoing aggressive anticancer therapy. Well designed, prospective randomised studies on infection control measures effective to prevent aspergillosis are lacking. Prophylactic systemic antifungal treatment with posaconazole significantly improves survival and reduces IA in acute myeloid leukaemia patients and reduces aspergillosis incidence rates in patients with intermediate-to-severe graft-versus-host reaction emerging after allogeneic haematopoietic stem cell transplantation. Voriconazole prophylaxis may be suitable for prevention of IA as well; however, the results of large clinical trials are still awaited.

Immunosuppressive preconditioning or induction regimens : evidence to date

The success of solid organ transplantation has been directly related to the development of immunosuppressive drug therapies. Preconditioning or induction therapy was developed to reduce early immunological and nonimmunological renal injury, with the goal of increasing long-term graft survival. However, the routine induction of immunological tolerance to solid organ allograft is currently not achievable because of the morbidity and mortality related to the immunosuppressive regimens themselves. The different therapeutic preconditioning or induction agents and their associated effects on cellular rejection, graft survival outcomes and the need for multiagent post-transplant maintenance therapy are reviewed.