High prevalence of hepatitis A and B nonimmunity in pediatric liver transplant recipients.

BACKGROUND: Pediatric liver transplant recipients are at increased risk of post-transplant infections. The purpose of this study was to quantify hepatitis A and B non-immunity based on antibody titers in liver transplant recipients. METHODS: We conducted a retrospective chart review of 107 pediatric liver transplant recipients at a single medical center from 2000 to 2017. We compared hepatitis immune patients to non-immune patients and studied response to vaccination in patients immunized post-transplantation. RESULTS: Eighty-one percent of patients had pre-transplant immunity to hepatitis A whereas 68% had pre-transplant immunity to hepatitis B. Post-transplant hepatitis B immunity decreased to 33% whereas post-transplant hepatitis A immunity remained high at 82%. Older age and time since transplantation were significantly associated with hepatitis B non-immunity. Most patients responded to doses post-transplantation with 78% seroconversion following hepatitis A re-immunization and 83% seroconversion following hepatitis B re-immunization. CONCLUSIONS: Pediatric liver transplant recipients are at risk of hepatitis A and B non-immunity, particularly with respect to hepatitis B. Boosters post-transplant may improve immunity to hepatitis viruses.

The role of donor-specific HLA alloantibodies in liver transplantation.

The impact of donor-specific HLA alloantibodies (DSA) on short- and long-term liver transplant outcome is not clearly defined. While it is clear that not all levels of allosensitization produce overt clinical injury, and that liver allografts possess some degree of alloantibody resistance, alloantibody-mediated adverse consequences are increasingly being recognized. To better define the current state of this topic, we assembled experts to provide insights, explore controversies and develop recommendations for future research on the consequences of DSA in liver transplantation. This article summarizes the proceedings of this inaugural meeting. Several insights emerged. Acute antibody-mediated rejection (AMR), although rarely diagnosed, is increasingly understood to overlap with T cell-mediated rejection. Isolated liver allograft recipients are at increased risk of early allograft immunologic injury when preformed DSA are high titer and persist posttransplantation. Persons who undergo simultaneous liver-kidney transplantation are at risk of renal AMR when Class II DSA persist posttransplantation. Other under-appreciated DSA associations include ductopenia and fibrosis, plasma cell hepatitis, biliary strictures and accelerated fibrosis associated with recurrent liver disease. Standardized DSA testing and diagnostic criteria for both acute and chronic AMR are needed to distil existing associations into etiological processes in order to develop responsive therapeutic strategies.

A common peripheral blood gene set for diagnosis of operational tolerance in pediatric and adult liver transplantation.

To identify biomarkers of operational tolerance in pediatric and adult liver transplant recipients, transcriptional profiles were examined from 300 samples by microarrays and Q-PCR measurements of blood specimens from pediatric and adult liver transplant recipients and normal tissues. Tolerance-specific genes were validated in independent samples across two different transplant programs and validated by Q-PCR. A minimal set of 13 unique genes, highly expressed in natural killer cells (p = 0.03), were significantly expressed in both pediatric and adult liver tolerance, irrespective of different clinical and demographic confounders. The performance of this gene set by microarray in independent samples was 100% sensitivity and 83% specificity and the AUC was 0.988 for only three genes by Q-PCR. 26% of adults and 64% of children with excellent liver allograft function, on minimal or dual immunosuppression, showed high prediction scores for tolerance. Novel peripheral transcriptional profiles can be identified in operational tolerance in pediatric and adult recipients of liver allografts, suggesting a high incidence of a pro-tolerogenic phenotype in stable patients on chronic immunosuppression. Given the high incidence of viral infections and malignancies in liver transplant recipients, this gene set provides an important monitoring tool that can move the field toward personalized and predictive medicine in organ transplantation.

Pediatric health-related quality of life after intestinal transplantation.

As outcomes after ITx improve, greater emphasis is needed on HRQOL. The primary aims of this study were to (i) assess the feasibility of measuring HRQOL in pediatric ITx recipients, (ii) measure HRQOL using validated instruments, and (iii) compare HRQOL in ITx recipients to healthy normal (NL) children. The CHQ and Pediatric Quality of Life (PedsQL4.0) instruments were administered to both patients and parents at outpatient visits. All 24 eligible patients were enrolled. The median age at study enrollment was 6.0 yr (range: 2-18 yr), and the median time from transplant to study enrollment was 2.8 yr (range: 0.5-11.8 yr). The majority of subjects were male (58%), Latino (58%), and liver-inclusive (92%) recipients. For CHQ and PedsQL4.0, parental responses were significantly lower in multiple categories including physical health and social functioning compared to healthy norms. Patient responses were not different from NL using CHQ but using PedsQL4.0 were significantly lower in the school functioning subcategory and psychosocial health summary score. HRQOL as reported by children and families after ITx is significantly lower in multiple categories compared to NL.

Differential cytokine and chemokine expression during rejection and infection following intestinal transplantation.

BACKGROUND/OBJECTIVES: Rejection and infectious enteritis in intestinal transplant (ITx) patients present with virtually identical symptoms. Currently, the gold standard for differentiating between these two conditions is endoscopy, which is invasive and costly. Our primary aim was to identify differences in peripheral blood cytokines during episodes of acute cellular rejection (ACR) and infectious enteritis in patients with intestinal transplants. METHODS: This was a prospective, cross-sectional study involving ITx patients transplanted between 2000 and 2016. We studied 63 blood samples collected from 29 ITx patients during periods of normal (n = 24) and abnormal (n = 17) allograft function. PBMCs from whole blood samples were cultured under unstimulated or stimulated conditions with phytohemagglutinin (PHA). The supernatant from these cultures were collected to measure cytokine and chemokine levels using a 38-plex luminex panel. RESULTS: Our study found that cytokines and chemokines are differentially expressed in normal, ACR, and infectious enteritis samples under unstimulated conditions based on heatmap analysis. Although each cohort displayed distinctive signatures, only MDC (p = 0.037) was found to be significantly different between ACR and infectious enteritis. Upon stimulation of PBMCs, patients with ACR demonstrated increased immune reactivity compared to infectious enteritis; though this did not reach statistical significance. CONCLUSIONS: To our knowledge, this is the first comprehensive study comparing cytokine expression during acute rejection and infectious enteritis in intestinal transplant recipients. Our results suggest that cytokines have the potential to be used as clinical markers for risk stratification and/or diagnosis of ACR and infectious enteritis.

Pediatric health-related quality of life: Feasibility, reliability and validity of the PedsQL transplant module.

The measurement properties of the newly developed Pediatric Quality of Life Inventory (PedsQL) 3.0 Transplant Module in pediatric solid organ transplant recipients were evaluated. Participants included pediatric recipients of liver, kidney, heart and small bowel transplantation who were cared for at seven medical centers across the United States and their parents. Three hundred and thirty-eight parents of children ages 2-18 and 274 children ages 5-18 completed both the PedsQL 4.0 Generic Core Scales and the Transplant Module. Findings suggest that child self-report and parent proxy-report scales on the Transplant Module demonstrated excellent reliability (total scale score for child self-report alpha= 0.93; total scale score for parent proxy-report alpha= 0.94). Transplant-specific symptoms or problems were significantly correlated with lower generic HRQOL, supporting construct validity. Children with solid organ transplants and their parents reported statistically significant lower generic HRQOL than healthy children. Parent and child reports showed moderate to good agreement across the scales. In conclusion, the PedsQL Transplant Module demonstrated excellent initial feasibility, reliability and construct validity in pediatric patients with solid organ transplants.

Pharmacokinetics of oral valganciclovir solution and intravenous ganciclovir in pediatric renal and liver transplant recipients.

In an open-label, prospective, pharmacokinetic assessment, we evaluated total drug exposure (area under the curve [AUC]) of intravenous (IV) ganciclovir (GCV) and oral (p.o.) valganciclovir when normalized for body surface area (BSA) in pediatric liver (n=20) and renal (n=26) transplant patients Reference doses for IV GCV (200 mg/m(2)) and p.o. valganciclovir (520 mg/m(2)) were based on adult doses, and adjusted for BSA initially, and BSA and renal function (estimated via creatinine clearance [CrCL]) thereafter. Renal transplant patients received GCV on days 1-2, valganciclovir 260 mg/m(2) on day 3, and valganciclovir 520 mg/m(2) on day 4. Liver transplant patients received twice daily GCV from enrollment to day 12, and then valganciclovir twice daily on days 13-14. GCV pharmacokinetics were described using a population pharmacokinetic approach. Type of solid organ transplant (kidney or liver) had no effect on GCV pharmacokinetics. Median GCV exposure following valganciclovir 520 mg/m(2) was similar to that with IV GCV, and to that reported in adults. Patients <5 years of age had AUC values approximately 50% of those compared with older age ranges; dosing based on both BSA and CrCL increased drug exposure in younger patients. A dosing algorithm based on BSA and CrCL should be tested in future studies.

The oversight of solid organ transplantation in the United States.

The publication of the Organ Procurement and Transplantation Network (OPTN) Final Rule in 2000 resulted in a new and different regulatory environment for solid organ transplantation in the United States. In this review the role of the OPTN in providing oversight is clarified, differentiating the powers of enforcement the OPTN and HHS possess compared to the importance of confidential peer review in promoting compliance with OPTN policies. The function of the OPTN's Membership and Professional Standards Committee (MPSC) in adjudicating center performance and investigating alleged violations is described as well as the type and impact of adverse actions that the MPSC can recommend. The role of the OPTN Board compared to that of the Secretary of HHS in determining adverse actions is differentiated. We describe MPSC's broad scope of work in the ongoing evaluation of performance of all transplant centers. Finally, the relationship between the OPTN oversight and other entities charged with safe health care practices in the United States is considered.

Preventable death: children on the transplant waiting list.

Children, especially those under 5 years of age, have the highest death rate on the transplant waiting list compared to any other age range. This article discusses the concept, supported by OPTN data, that there is an age range of small pediatric donors, which are almost exclusively transplanted into small pediatric transplant candidates. Allocation policies that allow broader sharing of small pediatric donors into small pediatric candidates are likely to decrease death rates of children on the waiting list. As well, although the number of pediatric deceased donors continues to decline, improving consent rates for eligible pediatric donors, and judicious use of pediatric donors after cardiac death, can enhance the pediatric deceased donor supply.

Risk factors for rejection and infection in pediatric liver transplantation.

Rejection and infection are important adverse events after pediatric liver transplantation, not previously subject to concurrent risk analysis. Of 2291 children (<18 years), rejection occurred at least once in 46%, serious bacterial/fungal or viral infections in 52%. Infection caused more deaths than rejection (5.5% vs. 0.6% of patients, p < 0.001). Early rejection (<6 month) did not contribute to mortality or graft failure. Recurrent/chronic rejection was a risk in graft failure, but led to retransplant in only 1.6% of first grafts. Multivariate predictors of bacterial/fungal infection included recipient age (highest in infants), race, donor organ variants, bilirubin, anhepatic time, cyclosporin (vs. tacrolimus) and era of transplant (before 2002 vs. after 2002); serious viral infection predictors included donor organ variants, rejection, Epstein-Barr Virus (EBV) naivety and era; for rejection, predictors included age (lowest in infants), primary diagnosis, donor-recipient blood type mismatch, the use of cyclosporin (vs. tacrolimus), no induction and era. In pediatric liver transplantation, infection risk far exceeds that of rejection, which causes limited harm to the patient or graft, particularly in infants. Aggressive infection control, attention to modifiable factors such as pretransplant nutrition and donor organ options and rigorous age-specific review of the risk/benefit of choice and intensity of immunosuppressive regimes is warranted.

Optimizing vascular access for patients receiving intravenous systemic therapy for early-stage breast cancer-a survey of oncology nurses and physicians.

Background: Despite advances in systemic therapy choices for patients with early-stage breast cancer, optimal practices for intravenous (IV) access remain unknown. That lack of knowledge holds particularly true for the use of central venous access devices (cvads) such as peripherally inserted central catheters (piccs) and implanted vascular access devices (ports). Methods: Using a survey of Canadian oncologists and oncology nurses responsible for the care of breast cancer patients, we evaluated current access practices, perceptions of complications, and perceptions of risk, and we estimated complication rates and evaluated perceived risk factors for lymphedema. Results: Survey responses were received from 25 physicians and 57 oncology nurses. Administration of trastuzumab or an anthracycline was associated with a higher likelihood of a cvad being recommended. Other factors associated with recommendation of a cvad included prior difficult IV access and a recommendation from the chemotherapy nurse. Although the complication rates perceived to be associated with the use of piccs and ports remained high, respondents felt that cvads might improve patient quality of life. Risk factors perceived to be associated with the risk of lymphedema were axillary lymph node dissection, radiation to the axilla, and line-associated infection. Factors known to be unrelated to lymphedema risk (specifically, blood draws and blood pressure measurement) continue to be perceived as posing a higher risk. Conclusions: Despite widespread use of chemotherapy for patients with breast cancer, the type of venous access used for treatment varies significantly, as do perceptions about the risks of cvad use and the risk for lymphedema development. Further prospective studies are needed to identify best-practice strategies.

Perceptions of vascular access for intravenous systemic therapy and risk factors for lymphedema in early-stage breast cancer-a patient survey.

Background: The choice of vascular access for systemic therapy administration in breast cancer remains an area of clinical equipoise, and patient preference is not consistently acknowledged. Using a patient survey, we evaluated the patient experience with vascular access during treatment for early-stage breast cancer and explored perceived risk factors for lymphedema. Methods: Patients who had received systemic therapy for early-stage breast cancer were surveyed at 2 Canadian cancer centres. Results: Responses were received from 187 patients (94%). The route of vascular access was peripheral intravenous line (IV) in 24%, a peripherally inserted central catheter (picc) in 42%, and a surgically inserted central catheter (port) in 34%. Anthracycline-based regimens were associated with a greater use of central vascular access devices (cvads- that is, a picc or port; 86/97, 89%). Trastuzumab use was associated with greater use of ports (49/64, 77%). Although few patients (7%) reported being involved in the decisions about vascular access, most were satisfied or very satisfied (88%) with their access type. Patient preference centred mainly on avoiding delays in the initiation of chemotherapy. Self-reported rates of complications (183 evaluable responses) were infiltration with peripheral IVs (9/44, 20%), local skin infections with piccs (7/77, 9%), and thrombosis with ports (4/62, 6%). Perceived risk factors for lymphedema included use of the surgical arm for blood draws (117/156, 75%) and blood pressure measurement (115/156, 74%). Conclusions: Most patients reported being satisfied with the vascular access used for their treatment. Improved education and understanding about the evidence-based requirements for vascular access are needed. Perceived risk factors for lymphedema remain variable and are not evidence-based.

Renal event outcomes in intestinal transplantation: results from a single-center experience.

BACKGROUND: Poor patient outcomes have been closely linked with perioperative renal function after most solid organ transplants, except intestinal transplantation (ITx). This study examined the effect of peri-ITx renal function on outcome. PATIENTS AND METHODS: A retrospective review of all patients undergoing ITx since 1991 was completed and included 43 patients and 49 transplants. Serum creatinine (sCr) and calculated glomerular filtration rate were compared with peri-ITx and out to 5 years. A renal event (RE) was defined as acute renal failure, immunotherapeutic change driven by poor renal function, or hemodialysis. Comparisons were made based on primary immunotherapeutic regimens-induction interleukin-2 receptor antagonist (IL-2RA; n=31) or standard tacrolimus-based therapy (STD; n=18). Data was analyzed using standard statistical analysis. RESULTS: The frequency of RE was: 60% (STD) versus 31% (IL-2RA) P<.05. RE-associated mortality was 63% (STD) and 27% (IL-2RA) P<.05. Overall mortality was associated with a RE in 50% (STD) and 37% (IL-2RA) of patients. Average sCr across all timepoints was 1.05 (STD) and 0.78 (IL-2RA) P<.003. Surviving patients with RE in STD tended to suffer prolonged renal insufficiency, whereas those in IL-2RA did not. CONCLUSION: This is the first study examining outcomes after ITx related to renal function. Clearly, renal function and RE impacted outcomes. Obtaining RE-free survival and lessening the impact of RE when they do occur is of paramount importance. It appears that IL-2RA immunotherapy reduces RE and their associated morbidity.

Nutritional outcomes following pediatric intestinal transplantation.

BACKGROUND: This study sought to describe the long-term nutritional outcomes of children after intestinal transplant (SBT). METHODS: Between 1991 and March 2005, 30 children received 33 SBT at a single center. Eligibility criteria included patient and graft survival >6 months. Weight, height, albumin, prealbumin, zinc (Zn), and essential fatty acid (EFA) levels were reviewed retrospectively. RESULTS: The 19 patients who met inclusion criteria had a median age at SBT of 2.9 years. The majority of patients were male, Latino, transplanted for necrotizing enterocolitis and received combined liver-SBT. All patients were weaned off total parenteral nutrition to elemental formula at a mean of 39 days post-SBT. Seventeen of 19 patients were Zn deficient and four patients were EFA deficient post-SBT. CONCLUSIONS: Pre-SBT most subjects were significantly deficient in anthropometric and biochemical parameters. Post-SBT the mean Z score for weight and height improved significantly at year 1, then leveled off in year 2. Serum protein levels improved from pre-SBT, yet remained low-normal. Zn deficiency was seen frequently after SBT and is under investigation. Children who developed EFA deficiency were on the same formula, receiving inadequate EFA supplementation. Successful SBT was associated with growth and maintenance of serum nutritional parameters but not with significant catch-up growth.

Identification of a sialic acid containing glycocalyx on the surface of Schistosoma mansoni.

Ruthenium red fixation of adult Schistosoma mansoni revealed the existence of a negatively charged layer external to the outer bilayer, which was morphologically similar to the glycocalyx of other cell types. Regional and sexual differences were found in the extent and organisation of the surface coat, which can be correlated with interfacial free energy, adhesiveness and protection from immune effectors. Neuraminidase treatment confirmed the presence of surface sialic acid. Mechanical or skin penetrated schistosomula, maintained in vitro for 24 h were found not to have a glycocalyx and this may relate to their increased susceptibility to immune killing. Lung stage schistosomula however, did bind ruthenium red to their surface.

Enrichment and partial enzyme characterization of ATPase activity associated with the outward-facing membrane complex and inward-facing membrane of the surface epithelial syncytium of Schistosoma mansoni.

The outward-facing (OFM) and inward-facing (IFM) membranes of the surface epithelial syncytium of Schistosoma mansoni were separated by sequential exposure to saponin solutions. The OFM, containing both inner and outer bilayers, contained ATPase activity that was stimulated by Mg2+ and Ma+, but not K+ or HCO-3, and was inhibited by Ca2+ and ethacrynic acid. The OFM enzyme was unaffected by ouabain, oligomycin, SCN- and azide and had a pH optimum of 7.5. The OFM ATPase therefore has properties similar to ATPases characterized from the apical membrane of a variety of epithelial cells where it is thought to augment the regulatory cell volume decreasing function of (Na++K+)Mg2+- ATPase. The IFM contained ATPase activity that was stimulated by Mg2+, Na+ and K+, and was inhibited by ouabain indicating the IFM enzyme was the Na+-pump ATPase. The results are discussed in terms of the transepithelial transport function of the surface epithelial syncytium and a Ca2+-ATPase reported previously from the OFM of S. mansoni.

Sequential removal of outer bilayer and apical plasma membrane from the surface epithelial syncytium of Schistosoma mansoni.

The outer and inner bilayers of the apical membrane complex of Schistosoma mansoni were sequentially stripped from adult worms by two incubations in 0.1% digitonin solutions. Membrane removal was evaluated by electron microscopy of worms and bilayer material, using Con A-ferritin as a marker for the outer bilayer. Amounts of Con A removed by the digests were measured with a tritiated Con A marker. To measure the purity of the fractions membrane markers were characterised and quantitated for both bilayers. In the absence of the usual enzymatic markers for plasma membrane diazotised [125I]-iodosulfanilic acid was used as a marker for the outer bilayer. Alkaline phosphatase and a Na+, Mg2+-ATPase were localised to the inner bilayer. From these results we can deduce that the inner bilayer is analogous to the typical, apical plasma membrane of other animal epithelia. The outer bilayer does not share these enzymatic similarities. The integrity of the syncytium after removal of the outer bilayer and the increased levels of lactate dehydrogenase in the supernatant after removal of the inner bilayer suggests that the outer bilayer is secondary in maintaining the permeability barrier of the apical membrane complex, with respect to soluble proteins. The possible significance of these results in terms of the destructive action of complement on the parasite are discussed.

Preparation and partial characterisation of a multilamellar body fraction from Schistosoma mansoni.

Multilaminate vesicles were purified, from homogenised whole Schistosoma mansoni adults, by differential density centrifugation on sucrose gradients, following methods previously employed for isolating multilamellar bodies (MLB) from mammalian lung. Morphometric analysis, on electron micrographs, of the pelleted fraction revealed that the pellet contained at least 56% MLB (by volume of solid material). An apparent projection core was described in both fixed MLB from our fraction and in unfixed MLB from a freeze thaw preparation of whole worms. The phospholipid-protein ratio of the MLB fraction was 1.6:1. The major phospholipid classes were separated and identified by quantitative, two dimensional, thin layer chromatography on silica gel. Phosphatidylcholine was the predominant phospholipid in the MLB fraction, comprising 57% of the total phospholipids. Phosphatidic acid phosphatase, previously reported from lung MLB but not schistosomes, was detected in the fraction. The high activity of this enzyme suggests a more active role for schistosome MLB than that of a mere reservoir of preformed membrane precursors.