Epidemiology and outcomes of Clostridium difficile infection in allogeneic hematopoietic cell and lung transplant recipients.

BACKGROUND: Clostridium difficile infection (CDI) is a common complication of lung and allogeneic hematopoietic cell (HCT) transplant, but the epidemiology and outcomes of CDI after transplant are poorly described. METHODS: We performed a prospective, multicenter study of CDI within 365 days post-allogeneic HCT or lung transplantation. Data were collected via patient interviews and medical chart review. Participants were followed weekly in the 12 weeks post-transplant and while hospitalized and contacted monthly up to 18 months post-transplantation. RESULTS: Six sites participated in the study with 614 total participants; 4 enrolled allogeneic HCT (385 participants) and 5 enrolled lung transplant recipients (229 participants). One hundred and fifty CDI cases occurred within 1 year of transplantation; the incidence among lung transplant recipients was 13.1% and among allogeneic HCTs was 31.2%. Median time to CDI was significantly shorter among allogeneic HCT than lung transplant recipients (27 days vs 90 days; P = .037). CDI was associated with significantly higher mortality from 31 to 180 days post-index date among the allogeneic HCT recipients (Hazard ratio [HR] = 1.80; P = .007). There was a trend towards increased mortality among lung transplant recipients from 120 to 180 days post-index date (HR = 4.7, P = .09). CONCLUSIONS: The epidemiology and outcomes of CDI vary by transplant population; surveillance for CDI should continue beyond the immediate post-transplant period.

Induction Immunosuppression and Clinical Outcomes in Kidney Transplant Recipients Infected With Human Immunodeficiency Virus.

There is an increased risk of acute rejection (AR) in human immunodeficiency virus-positive (HIV+) kidney transplant (KT) recipients. Induction immunosuppression is standard of care for those at high risk of AR; however, use in HIV+ patients is controversial, given fears of increased infection rates. We sought to compare clinical outcomes between HIV+ KT recipients who were treated with (i) anti-thymocyte globulin (ATG), (ii) IL-2 receptor blocker, and (iii) no induction. We studied 830 HIV+ KT recipients between 2000 and 2014, as captured in the Scientific Registry of Transplant Recipients, and compared rates of delayed graft function (DGF), AR, graft loss and death. Infections and hospitalizations were ascertained by International Classification of Diseases, Ninth Revision codes in a subset of 308 patients with Medicare. Compared with no induction, neither induction agent was associated with an increased risk of infection (weighted hazard ratio [wHR] 0.80, 95% confidence interval [CI] 0.55-1.18). HIV+ recipients who received induction spent fewer days in the hospital (weighted relative risk [wRR] 0.70, 95% CI 0.52-0.95), had lower rates of DGF (wRR 0.66, 95% CI 0.51-0.84), less graft loss (wHR 0.47, 95% CI 0.24-0.89) and a trend toward lower mortality (wHR 0.60, 95% CI 0.24-1.28). Those who received induction with ATG had lower rates of AR (wRR 0.59, 95% CI 0.35-0.99). Induction in HIV+ KT recipients was not associated with increased infections; in fact, those receiving ATG, the most potent agent, had the lowest rates. In light of the high risk of AR in this population, induction therapy should be strongly considered.

Solid organ transplantation from hepatitis B virus-positive donors: consensus guidelines for recipient management.

Use of organs from donors testing positive for hepatitis B virus (HBV) may safely expand the donor pool. The American Society of Transplantation convened a multidisciplinary expert panel that reviewed the existing literature and developed consensus recommendations for recipient management following the use of organs from HBV positive donors. Transmission risk is highest with liver donors and significantly lower with non-liver (kidney and thoracic) donors. Antiviral prophylaxis significantly reduces the rate of transmission to liver recipients from isolated HBV core antibody positive (anti-HBc+) donors. Organs from anti-HBc+ donors should be considered for all adult transplant candidates after an individualized assessment of the risks and benefits and appropriate patient consent. Indefinite antiviral prophylaxis is recommended in liver recipients with no immunity or vaccine immunity but not in liver recipients with natural immunity. Antiviral prophylaxis may be considered for up to 1 year in susceptible non-liver recipients but is not recommended in immune non-liver recipients. Although no longer the treatment of choice in patients with chronic HBV, lamivudine remains the most cost-effective choice for prophylaxis in this setting. Hepatitis B immunoglobulin is not recommended.

KIR and HLA interactions are associated with control of primary CMV infection in solid organ transplant recipients.

Cytomegalovirus (CMV) infection remains a major source of morbidity and mortality in solid organ transplant recipients. Killer immunoglobulin-like receptors(KIR) are genetically polymorphic natural killer(NK) cell receptors important in antiviral responses. A retrospective, single-center cohort study was performed to study the interaction of KIR genotype and primary control of CMV infection after transplantation.Time to first CMV viremia was determined for a cohort of 531 CMV serology donor positive/recipient negative solid organ transplant recipients. Of the KIR genes,KIR2DL3 and KIR2DS2 were most strongly associated with time to CMV viremia in random survival forest analysis. As KIR2DL3 and KIR2DS2 both interact with HLA-C1, these interactions were evaluated. Seventy six recipients were found to be positive for both KIR2DL3 and KIR2DS2 and expressed only HLA-C1 antigens in both recipient and donor. These patients had a substantially reduced hazard of CMV viremia in the first year after solid organ transplantation (hazard ratio 0.44, 95% CI 0.27­0.72, p=0.0012). In KIR2DL3+/KIR2DS2+/HLA-C1/1 recipients who received an organ from a non-C1/1 donor, this protective effect was not observed. These results improve our understanding of human NK cell function in primary CMV infection after transplant.

Mycobacterium llatzerense lung infection in a liver transplant recipient: case report and review of the literature.

Nontuberculous mycobacteria are increasingly encountered pathogens in organ transplant recipients. We report the first case of human disease attributed to Mycobacterium llatzerense that occurred in a liver transplant recipient in the midwestern United States who developed pneumonia and describe the treatment of this patient.

Influenza vaccination in the organ transplant recipient: review and summary recommendations.

Influenza virus causes a spectrum of illness in transplant recipients with a high rate of lower respiratory disease. Seasonal influenza vaccination is an important public health measure recommended for transplant recipients and their close contacts. Vaccine has been shown to be safe and generally well tolerated in both adult and pediatric transplant recipients. However, responses to vaccine are variable and are dependent on various factors including time from transplantation and specific immunosuppressive medication. Seasonal influenza vaccine has demonstrated safety and no conclusive evidence exists for a link between vaccination and allograft dysfunction. Annually updated trivalent inactivated influenza vaccines have been available and routinely used for several decades, although newer influenza vaccination formulations including high-dose vaccine, adjuvanted vaccine, quadrivalent inactivated vaccine and vaccine by intradermal delivery system are now available or will be available in the near future. Safety and immunogenicity data of these new formulations in transplant recipients requires investigation. In this document, we review the current state of knowledge on influenza vaccines in transplant recipients and make recommendations on the use of vaccine in both adult and pediatric organ transplant recipients.

Lung transplantation in a recipient with novel 2009 H1N1 influenza: lessons learned.

Immunosuppressed patients are at an increased risk for severe disease from influenza A (H1N1). We report a case of a patient who died of septic complications from H1N1 acquired at the time of single lung transplant.

Oral maribavir for treatment of refractory or resistant cytomegalovirus infections in transplant recipients.

BACKGROUND: Despite advances in cytomegalovirus (CMV) prophylaxis and therapy, some transplant recipients still develop refractory CMV infections. Maribavir (MBV), an investigational benzimidazole antiviral agent, acts by a mechanism different from that of existing anti-CMV drugs. Previous Phase I and II studies have demonstrated a favorable safety profile for MBV, but its utility in treatment of complex CMV syndromes is unknown. METHODS: Between June and December 2008, MBV was released for use under individual emergency investigational new drug applications requested by treating physicians and approved by the US Food and Drug Administration and local institutional review boards. Six patients (5 solid organ transplant recipients and 1 hematopoietic stem cell transplant recipient) who had failed to respond to other therapies and/or had known ganciclovir-resistant CMV were treated with MBV at a starting oral dose of 400 mg twice daily. RESULTS: Patients were treated for a median of 207 days (range, 15-376). Four of 6 patients had no detectable CMV DNAemia within 6 weeks of starting MBV therapy. One patient, who had an initial viral load of 1.8 million copies/mL, developed MBV resistance mutations. One patient, who had low serum levels of MBV, had persistent CMV DNAemia and viruria without developing genotypic or phenotypic resistance to MBV. One patient cleared CMV DNAemia, but died of pneumonia and multiorgan failure. No significant adverse effects attributable to MBV were observed. CONCLUSIONS: MBV deserves further systematic evaluation as treatment for CMV infection that is resistant and/or refractory to standard therapies, but its optimal dose, duration of therapy, and use in combinations versus as a single agent have yet to be determined.

Histoplasmosis in solid organ transplant recipients: 10 years of experience at a large transplant center in an endemic area.

BACKGROUND: Many clinical scenarios have been encountered by patients who developed histoplasmosis after receiving a solid organ transplant at a large transplant center in an endemic area. METHODS: Cases of posttransplantation histoplasmosis were identified by use of multiple methods, including reviews of microbiology test results, transplant databases, and billing codes. Data were obtained retrospectively. Descriptive statistics were used. RESULTS: During the 1997-2007 study period, 3436 patients received a solid organ transplant, and 38 patients were identified as having posttransplantation histoplasmosis. Of these 38 patients, 9 were excluded from our study because the diagnosis was solely clinical. Of the remaining 29 patients, 14 had posttransplantation histoplasmosis (incidence, 1 case per 1000 person-years); 14 showed histologic evidence of histoplasmosis in the recipient or donor tissue, which was encountered unexpectedly at the time of transplantation; and 1 had histoplasmosis before receiving the transplant. Of the 14 patients who developed histoplasmosis after transplantation, 5 were heart transplant recipients, 3 were lung transplant recipients, 3 were kidney transplant recipients, 1 was a liver transplant recipient, 1 was a pancreas transplant recipient, and 1 was a kidney-pancreas transplant recipient. The median time from transplantation to diagnosis was 17 months (interquartile range, 8.1-46 months), and the median time from onset of symptoms to diagnosis 3 weeks (interquartile range, 1.9-6.5 weeks). All recipients had disseminated disease. The most common treatment was amphotericin B and itraconazole. All were cured, or still on treatment, but symptom-free. Of the 14 patients who had an explanted organ or donor tissue that showed histologic evidence of histoplasmosis, 13 (93%) were lung transplant recipients, and 1 (7%) was a liver transplant recipient. None of these patients developed active histoplasmosis, but all received prophylactic treatment. Finally, 1 patient had histoplasmosis before transplantation; he was treated with itraconazole 3 months before and after transplantation, and he did well. CONCLUSIONS: In conclusion, posttransplantation histoplasmosis is rare (1 case per 1000 transplant-person-years; 95% confidence interval, 0.6-1.7), even in endemic areas. Prognosis is good but requires protracted therapy. Patients with latent infection did not develop posttransplantation histoplasmosis when prophylaxis was used.

Update on immunizations in solid organ transplant recipients: what clinicians need to know.

Vaccine-preventable diseases remain a major source of morbidity and mortality in transplant recipients. Since the publication of the American Society of Transplantation's guidelines for vaccination of solid organ transplant recipients in 2004 (1), several new vaccines have been licensed. Transplant clinicians have been inundated by questions from patients and colleagues regarding the utility and safety of these vaccines in transplant candidates and recipients. In addition, new data has appeared regarding utility of some established vaccines, lack of rejection after vaccination and newer adjuvant strategies. Literature published between 2004 and 2007 was reviewed in a Medline search. Guidelines from the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices are reviewed and summarized, with particular attention to vaccines for human papillomavirus, varicella and varicella-zoster, tetanus-reduced diphtheria-acellular pertussis (Tdap) and hepatitis B, as well as conjugated meningococcal and conjugated pneumococcal vaccines. Although randomized controlled trials in transplant recipients have not been performed for most new licensed vaccines, preliminary recommendations can be formulated based on current data and guidelines. Further studies will be important to determine the indications and optimal timing of newer immunizations and immunization strategies.

Inhibition of cytotoxic T-lymphocyte-triggered apoptosis by target cell surface-coupled aprotinin.

A variety of recent investigations have implicated granzymes A and/or B in the target cell nuclear injury which accompanies cytotoxic T-lymphocyte-mediated cytolysis. Since soluble antiproteases have had limited efficacy in inhibiting CTL-mediated lysis, we developed a method to couple aprotinin, a peptide inhibitor of serine proteases, to the surface of target cells. Aprotinin modified by N-succinimidyl 3-(2-pyridyldithio)propionate retained trypsin-inhibitory activity, and target cells modified with aprotinin had demonstrable cell surface trypsin-inhibitory activity. Flow cytometry demonstrated that aprotinin was detectable on the target cell surface but underwent modulation at a rather rapid rate. When radiolabeled, aprotinin-coupled target cells were studied in 1-2 hr CTL assays, 51Cr release was little affected, but 125IUdR release was reduced up to 75% compared to controls. Corresponding apoptosis analysed by agarose gel electrophoresis and direct cytologic visualization was similarly reduced. Thus, aprotinin bound to the surface of target cells selectively protected target cells against CTL-mediated nuclear injury, and may serve as a model for the development of novel inhibitors of CTL-mediated lysis.

Significance of positive cultures from donor left atrium and postpreservation fluid in heart transplantation.

BACKGROUND: The significance of positive perioperative cultures routinely obtained from the donor left atrium and postpreservation fluid during heart transplantation is unknown. METHODS: A retrospective chart review of 128 heart transplant recipients was done. RESULTS: A total of 106 of 128 patients had left atrial and/or postpreservation fluid cultures performed; 61 (57.5%) of them were positive. Forty-one positive left atrial or postpreservation cultures grew indolent organisms and 20 grew virulent organisms. Six donors had positive blood cultures, and five of the six did not have left atrial or postpreservation fluid cultures positive for the same organism. Seven recipients had positive blood cultures with organisms different from their corresponding left atrial or postpreservation fluid cultures. Three patients had sternal wound infections with organisms different from their donors' left atrial or postpreservation fluid cultures. Seven patients received additional antibiotics after heart transplantation specifically directed at a positive left atrial or postpreservation fluid culture for 5 to 7 days; none of them developed infection with these organisms. CONCLUSIONS: We found no evidence that positive donor left atrium or postpreservation fluid cultures increase the recipients' risk of infection. Nevertheless, we cannot refute that the small group of patients who received additional antibiotics might have developed an infection if they had not been treated. We recommend that the left atrial and postpreservation fluid cultures growing indolent organisms be discounted. However, if they grow more virulent organisms, consideration could be given to a brief course of specific therapy while awaiting recipient cultures.

A randomized prospective controlled trial of oral acyclovir versus oral ganciclovir for cytomegalovirus prophylaxis in high-risk kidney transplant recipients.

BACKGROUND: Posttransplantation cytomegalovirus (CMV) infection remains a significant cause of morbidity in kidney transplant recipients. We performed a randomized prospective controlled trial of oral acyclovir versus oral ganciclovir for CMV prophylaxis in a group of renal allograft recipients considered at high risk for CMV disease due to the use of OKT3 induction therapy. METHODS: A total of 101 recipients of cadaveric (83) and zero haplotype-matched live donor (18) kidney transplants were entered into the trial. A total of 22 D-R- patients received no prophylaxis. Twenty-seven D+R-, 29 D+R+, and 23 D-R+ patients were randomized to receive 3 months of either oral acyclovir (800 mg q.i.d.) or oral ganciclovir (1000 mg t.i.d.). Doses were adjusted according to the level of renal function. The D+R- patients were also given CMV immune globulin biweekly for 16 weeks. Surveillance blood cultures were obtained at transplantation, at months 1, 2, 3, and 6, and when clinically indicated. The primary study end points were time to CMV infection and disease the first 6 months after transplantation. RESULTS: The mean follow up was 14.4 months. Both agents were well tolerated, and no drug interruptions for toxicity occurred. CMV was isolated in 14 of 39 (35.9%) acyclovir-treated and 1 of 40 (2.5%) ganciclovir-treated recipients by 6 months (P=0.0001). Symptomatic CMV disease occurred in 9 of 14 (64%) of the acyclovir patients, two with tissue-invasive disease. Infection rates for acyclovir vs. ganciclovir, respectively, stratified by CMV serology were: D+R-, 54 vs. 0%, P=0.0008; D+R+, 43 vs. 6.6%, P=0.01; D-R+, 8.3 vs. 0%, P=NS. No patient developed CMV infection while taking oral ganciclovir, however three delayed infections occurred 2-7 months after finishing therapy. Each patient had been previously treated for acute rejection. CONCLUSIONS: Oral acyclovir provides effective CMV prophylaxis only for recipients of seronegative donor kidneys. Oral ganciclovir is a superior agent providing effective CMV prophylaxis for recipients of seropositive donor kidneys. Recipients who are treated for acute rejection are at risk for delayed CMV infection during the first posttransplantation year.

Hypogammaglobulinemia in lung transplant recipients.

BACKGROUND: Infectious complications continue to represent a significant source of morbidity and mortality in lung transplant recipients. Identifying specific, remediable immune defects is of potential value. After one lung transplant patient with recurrent infections was noted to be severely hypogammaglobulinemic, a screening program for humoral immune defects was instituted. The objectives were to define the prevalence of hypogammaglobulinemia in lung transplant recipients, assess levels of antibody to specific pathogens, and correlate infectious disease outcomes and survival with immunoglobulin levels. METHODS: All lung transplant recipients followed at a single center between October 1996 and June 1999 underwent a posttransplant humoral immune status survey as part of routine posttransplant follow-up. This survey consists of total immunoglobulin levels (IgG, IgM, IgA), IgG subclasses (IgG1-4), and antibody titers to Pneumococcus, diphtheria, and tetanus. Since February 1997, this survey has been incorporated into the pretransplant evaluation as well. Humoral survey results for October 1996 through July 1999 were recorded, and clinical information on major infectious disease outcomes was obtained from chart reviews, discharge summaries, the Cleveland Clinic Unified Transplant Database, and review of all microbiological studies and pathology results for each patient. RESULTS: Of 67 patients with humoral immune surveys drawn posttransplant, 47 (70%) had IgG levels less than 600 mg/dl (normal 717-1410 mg/dl), of which 25 (37%) had IgG levels less than 400 mg/dl ("lowest IgG group") and 22 (33%) had IgG levels between 400 and 600 mg/dl ("moderately low IgG group"). A total of 20 patients (30%) had IgG levels of more than 600 mg/dl ("normal IgG group"). Infections that were significantly more common in the lowest IgG group, and more common in the moderately low IgG group than the normal IgG group, included: number of pneumonias (P=0.0006), bacteremias (P=0.02), total bacterial infections (P=0.002), tissue-invasive cytomegalovirus (P=0.01), invasive aspergillosis (P=0.001), total fungal infections (P=0.001), and total infections (P=0.006). Median hospital days per posttransplant year was significantly different in the three groups (11.0 vs. 7.4 vs. 2.8 days, P=0.0003.) Invasive aspergillosis occurred in 44% of the lowest IgG group, 9% of the moderately low IgG group, and 0% of the normal IgG group (P<0.001). Survival was poorest in the lowest IgG group and intermediate in the moderately low IgG group. IgG subclass deficiencies occurred in a variety of patterns. Hypogammaglobulinemic patients lacked protective responses to Pneumococcus in 14/47 (30%), diphtheria in 15%, and tetanus in 19%. In a group of 48 patients screened pretransplant, 90% had normal immunoglobulin levels. CONCLUSIONS: Hypogammaglobulinemia in lung transplant recipients is more common than has been previously recognized. An IgG level of less than 400 mg/dl identifies a group at extremely high risk of bacterial and fungal infections, tissue-invasive cytomegalovirus, and poorer survival. Immunoglobulin monitoring may offer an opportunity for intensive surveillance, tapering of immunosuppression, and preemptive therapy for infection.

A survey of allogeneic bone marrow transplant programs in the United States regarding cytomegalovirus prophylaxis and pre-emptive therapy.

Despite an extensive literature, no consensus has emerged regarding the optimal preventive strategy for CMV in allogeneic bone marrow transplantation (BMT). No survey of CMV prevention in BMT centers in the United States has yet been published. A questionnaire was sent to all allogeneic BMT programs in the United States, as listed in the November 1998 National Marrow Donor Program (NMDP) address roster. Questions included whether universal prophylaxis, pre-emptive therapy, or some other strategy was used for CMV prevention, and which CMV diagnostic tests were utilized. Eighty-one of 96 programs (86%) responded to the survey. Of these, 46 (56%) utilize a pre-emptive ganciclovir strategy, whereas 17 (21%) utilize universal prophylaxis, and 15 (19%) utilize a hybrid strategy based on risk stratification. The most commonly utilized CMV diagnostic tests are CMV-DNA by PCR (55 centers), shell vial centrifugation culture (52), tissue culture (42), pp65 antigenemia assay (38), and CMV-DNA by Digene hybrid capture (14). Of these, the CMV-DNA by PCR, pp65 antigenemia assay, and shell vial culture are the most frequently utilized as triggers for pre-emptive therapy. Quantitative assays are common (PCR 42%, Digene 64%). We conclude that centers currently performing allogeneic BMT in the United States employ a variety of strategies for CMV prevention, and differ in their diagnostic tests of choice for CMV monitoring. These results emphasize the need for large-scale studies to identify optimal diagnostic and management protocols. Bone Marrow Transplantation (2000) 26, 763-767.