Posttransplant Lymphoproliferative Disorder in Adults Receiving Kidney Transplantation in British Columbia: A Retrospective Cohort Analysis.

BACKGROUND: Posttransplant lymphoproliferative disorder (PTLD) is a major complication following kidney transplantation. OBJECTIVE: We undertook this study to characterize PTLD in kidney transplant patients in British Columbia with regard to incidence, patient and graft survival, histological subtypes, treatment modalities, and management of immunosuppression. DESIGN: Retrospective cohort analysis. SETTING: British Columbia. PATIENTS: All adult patients who underwent kidney transplantation in British Columbia between January 1, 1996, and December 31, 2012, were included. Patients less than 18 years of age at the time of first transplant and multiple organ transplant recipients were excluded from analysis. MEASUREMENTS: Patients with lymphoproliferative disorders that occurred subsequent to kidney transplantation were considered to have developed PTLD. METHODS: Cases of PTLD were identified by cross-referencing data abstracted from the provincial transplant agency's clinical database with the provincial cancer agency's lymphoma registry. Patients were followed up for the development of PTLD until December 31, 2012, and for outcomes of death and graft failure until December 31, 2014. Data collection was completed via an electronic chart review. RESULTS: Of 2217 kidney transplant recipients, 37 (1.7%) developed PTLD. Nine cases were early-onset PTLD, occurring within 1 year of transplant; of these cases, 6 were known/presumed Epstein-Barr virus mismatch, compared with only 2 of 28 late-onset cases. Patient survival for early-onset PTLD was 100% at 2 years post diagnosis. Late-onset PTLD had survival rates of 71.4% and 67.9% at 1 and 2 years, respectively. PTLD was associated with significantly decreased patient survival (P = .031) and graft survival (uncensored for death, P = .017), with median graft survival of PTLD and non-PTLD patients being 9.5 and 16 years, respectively. Immunosuppressant therapy was reduced in the majority of patients; additional therapies included rituximab monotherapy, CHOP-R, radiation, and surgery. LIMITATIONS: Limitations to this study include its retrospective nature and the unknown adherence of patients to prescribed immunosuppressant regimens. In addition, cumulative doses of immunosuppression received and the degree of immunosuppression reduction for PTLD management were not effectively captured. CONCLUSIONS: The incidence of PTLD in British Columbia following kidney transplantation was low and consistent with rates reported in the literature. The incidence of late-onset PTLD and its association with reduced patient and graft survival warrant further analysis of patients' long-term immunosuppression.

CONTEXTE: Le syndrome lymphoprolifératif post-greffe (SLPG) est une complication grave survenant à la suite d'une transplantation rénale. OBJECTIF DE L'ÉTUDE: Nous avons mené cette étude afin de caractériser le SLPG chez les receveurs d'une greffe rénale en Colombie-Britannique en ce qui a trait à son incidence, à la survie du patient et du greffon, aux sous-types histologiques, aux modalités de traitement et à la gestion de l'immunosuppression. CADRE ET TYPE D'ÉTUDE: Il s'agit d'une étude de cohorte rétrospective effectuée en Colombie-Britannique. SUJETS: Ont été inclus dans l'étude tous les patients adultes ayant subi une transplantation rénale entre le 1er janvier 1996 et le 31 décembre 2012 en Colombie-Britannique. Les patients âgés de moins de 18 ans au moment de l'intervention et les patients receveurs de greffe de multiples organes ont été exclus. MESURES: Tout cas de SL apparu après une greffe rénale étaient considérés comme un SLPG. MÉTHODOLOGIE: Les cas de SLPG ont été répertoriés en recoupant les données extraites de la base de données cliniques de l'agence provinciale de transplantation avec les données du registre des lymphomes tenu par l'agence provinciale de lutte contre le cancer. Les participants ont été suivis jusqu'au 31 décembre 2012 pour l'apparition du SLPG et jusqu'au 31 décembre 2014 pour les issues défavorables telles que la mort du patient ou le rejet du greffon. L'examen du dossier électronique des patients a complété la collecte des données. RÉSULTATS: Des 2 217 receveurs d'une greffe rénale répertoriés, seuls 37 (1,7 %) ont développé un SLPG. L'apparition du SLPG s'est faite de façon précoce, soit dans la première année post-greffe, pour neuf de ces patients, dont six représentaient un cas connu ou présumé de non-concordance pour le virus d'Epstein Barr (EBV). En comparaison, seuls deux des 28 patients ayant expérimenté un développement tardif du SLPG étaient présumés non-concordants pour l'EBV. Deux ans après le diagnostic, 100 % des patients ayant eu une apparition précoce du SLPG avaient survécu. Dans les cas de développement tardif de la maladie, le taux de survie passait à 71,4 % après un an et à 67,9 % après deux ans pour les patients. Le développement du SLPG a été associé avec une réduction significative de la chance de survie du patient (p = 0,031) et du greffon (p = 0,017, cas de décès non censurés). La survie médiane du greffon était de 9,5 ans pour les patients ayant développé un SLPG alors qu'elle était de 16 ans pour les autres. L'intensité du traitement immunosuppresseur a pu être réduite pour la majorité des patients. Les traitements additionnels incluaient la monothérapie au rituximab, le R-CHOP, la radiation et la chirurgie. LIMITES DE L'ÉTUDE: La nature rétrospective de l'étude est un facteur limitant la portée de nos résultats, de même que l'absence de données sur l'adhérence des patients au traitement immunosuppressif. De plus, nous n'avons pu mesurer précisément les doses cumulatives d'immunosuppresseurs reçues, ni le degré de réduction de ces derniers dans la prise en charge du SLPG. CONCLUSION: En Colombie-Britannique, l'incidence du SL post-greffe rénale s'est avérée faible et cohérente avec les taux rapportés dans la littérature. L'incidence de l'apparition tardive du SLPG et son association à un taux et une durée de survie amoindris (à la fois pour le patient et pour le greffon) justifient une analyse plus poussée de l'immunosuppression à long terme dans la population en question.

El uso de la presión positiva espiratoria final (PPEF) en el manejo de la insuficiencia respiratoria aguda / The use of final positive expiratory pressure (FPEP) in the management of acute respiratory failure / O uso da pressão positiva expiratória final (PEEP) no tratamento da insuficiência respiratória aguda

Resumen: Se analiza el efecto de la presión positiva espiratoria final (PPEF) en un grupo de pacientes con insuficiencia respiratoria aguda (IRA) de muy diversa etiología. Del mismo modo se analiza la evolución y otros aspectos del manejo ventilatorio de estos casos. La sola administración de la PPEF modificó en forma significativa y favorable varios de los parámetros respiratorios evaluados: aumento de la PaO2, disminución del índice FiO2/PaO2, disminución del Qs/Qt y del gradiente A-aDO2. No hubo alteración hemodinámica manifiesta a través de los parámetros clínicos: presión arterial, frecuencia cardiaca y diuresis, tampoco hubo alteraciones significativas del gradiente a-vDO2. Complicaciones atribuidas a la PPEF del tipo del «barotrauma¼ fueron encontrados en el 10.4% de los casos. El curso de la IRA fue hacia la mejoría en la mayoría de los pacientes al final de la evolución. La elevada tasa de mortalidad en este grupo de pacientes es atribuida a la presencia de sepsis no controlable y a la coexistencia de múltiples fallas orgánicas. En ninguno de los casos fue atribuida a hipoxemia aguda refractaria. La PPEF, una de las variedades de presión positiva continua, manejada en el concepto de «PPEF óptima¼, representa uno de los avances terapéuticos más importantes de la última década en el manejo de los pacientes con IRA.

Abstract: A group of 19 patients with acute respiratory failure (ARF) of diverse etiology received as a part of their treatment positive end expiratory pressure (PEEP). All of them were evaluated clinicaly and with several respiratory parameters. The response to treatment, complications and mortality rates are analyzed. The addition of PEEP in the management of this patients was accompanied by a significant increase of the PAO2 (p < 0.001) and a simultaneous decrease in the following parameters: FiO2/PaO2 index, Alveolo-arterial oxygen gradient (A-aDO2) and the pulmonary shunt (Qs/Qt). No hemodynamic deterioration was observed. None of the clinical parameters such as: blood pressure, heart rate and diuresis was significantly modified; neither a significant change in the arterious-venous oxygen gradient (a-vDO2) was detected. Pneumothorax as a complication of the use of PEEP was present in the 10.4% of the patients. The course of the ARF was toward the improvement in most of them at the end of the evolution. The high mortality rate in this study was considered to be secondary to uncontrolable sepsis and also to the presence of multiple organ failure. In none of the cases the poor outcome was secondary to refractory acute hypoxemia. PEEP which is one of the varieties of continuos positive pressure ventilation (CPPV) represents one of the most importants therapeutic advances in the last decade in the management of patients with acute respiratory failure.

Résumé: On analyse l'effet de la pression positive expiratoire finale (PPEF) dans un groupe de patients avec Insuf-misance respiratoire aiguë (IRA) d'une très diverse étiologie. De la même façon on analyse l'évolution et d'autres aspects du maniement ventriculaire de ces cas. La seule administration de la PPEF a modifié dans une forme significative et favorable plusieurs des paramètres respiratoires évalués: augmentation de la PaO2, diminution de I'ndice FiO2/PaO2, diminution du Qs/Qt et du gradient A-aDD2. Il n'y a pas eu d'altération hémodynamique manifeste à travers les paramètres cliniques: pression artérielle, fréquence cardiaque et diurèse, il n'y a pas eu non plus des altérations significatives du gradient a-vDO2. Des complications attribuées à la PPEF du type du «barotraume¼ ont été trouvées dans le 10.4% des cas. Le cours de l'IRA a tendu vers l'amélioration chez la plupart des patients à la fin de l'évolution. Le taux élevé de mortalité dans ce groupe de patients est attribué à la présense de sepsis non contrôlable et à la coexitance de multiples défauts organiques. Dans aucun des cas il a été attribué à hypoxémia aiguë réfractaire. La PPEF, une des variétés de pression positive continue, maniée dans le concept de «PPEF très bonne¼, représente l'un des avancements thérapeutiques les plus importants des dix dernières années dans le maniement des patients avec IRA.

Diagnosis and management of splenic injury following colonoscopy: algorithm and case series.

BACKGROUND: Splenic injury following colonoscopy is a rare yet life-threatening complication. These injuries are often associated with delayed diagnosis and may require invasive intervention. We sought to study the emergent presentation associated with splenic injury post-colonoscopy and to suggest a new treatment algorithm. METHODS: Six cases of splenic injury following colonoscopy were collected from three medical centers. Data regarding patient medical history, clinical presentation, laboratory and imaging findings and clinical management were recorded. A systematic PubMed/MEDLINE search was performed. Non-English-language publications and publications dating earlier than 2010 were excluded. An emergency department trauma-based management algorithm was designed according to the identified publications and review of the available trauma literature. RESULTS: The mean age was 65.3 years and the male-to-female ratio was 1:5. Five of the cases presented within 24 h of the colonoscopy complaining of severe abdominal pain. Hemodynamic instability was noted in four patients who presented with tachycardia (105-130), hypotension and/or a rapid drop in hemoglobin levels. All of the patients underwent initial resuscitation and a computerized abdominal tomography scan. Four of them required emergent splenectomy. No mortality or major morbidity was reported following the hospitalization. CONCLUSIONS: Although very rare, splenic injury during colonoscopy is an acute, severe and possible fatal complication. Patients may present with a rapid clinical deterioration and hemodynamic instability. Physicians should be familiar with the practical management of this surgical emergency and the treatment options available.

Commercially available immunoglobulins contain virus neutralizing antibodies against all major genotypes of polyomavirus BK.

Neutralizing antibodies (NAbs) form the basis of immunotherapeutic strategies against many important human viral infections. Accordingly, we studied the prevalence, titer, genotype-specificity, and mechanism of action of anti-polyomavirus BK (BKV) NAbs in commercially available human immune globulin (IG) preparations designed for intravenous (IV) use. Pseudovirions (PsV) of genotypes Ia, Ib2, Ic, II, III, and IV were generated by co-transfecting a reporter plasmid encoding luciferase and expression plasmids containing synthetic codon-modified VP1, VP2, and VP3 capsid protein genes into 293TT cells. NAbs were measured using luminometry. All IG preparations neutralized all BKV genotypes, with mean EC50 titers as high as 254 899 for genotype Ia and 6,666 for genotype IV. Neutralizing titers against genotypes II and III were higher than expected, adding to growing evidence that infections with these genotypes are more common than currently appreciated. Batch to batch variation in different lots of IG was within the limits of experimental error. Antibody mediated virus neutralizing was dose dependent, modestly enhanced by complement, genotype-specific, and achieved without effect on viral aggregation, capsid morphology, elution, or host cell release. IG contains potent NAbs capable of neutralizing all major BKV genotypes. Clinical trials based on sound pharmacokinetic principles are needed to explore prophylactic and therapeutic applications of these anti-viral effects, until effective small molecule inhibitors of BKV replication can be developed.

Post-transplant lymphoproliferative disorder after pancreas transplantation: a United Network for Organ Sharing database analysis.

There are not a great deal of data on post-transplant lymphoproliferative disorder (PTLD) following pancreas transplantation. We analyzed the United Network for Organ Sharing national database of pancreas transplants to identify predictors of PTLD development. A univariate Cox model was generated for each potential predictor, and those at least marginally associated (p < 0.15) with PTLD were entered into a multivariable Cox model. PTLD developed in 43 patients (1.0%) of 4205 pancreas transplants. Mean follow-up time was 4.9 ± 2.2 yr. In the multivariable Cox model, recipient EBV seronegativity (HR 5.52, 95% CI: 2.99-10.19, p < 0.001), not having tacrolimus in the immunosuppressive regimen (HR 6.02, 95% CI: 2.74-13.19, p < 0.001), recipient age (HR 0.96, 95% CI: 0.92-0.99, p = 0.02), non-white ethnicity (HR 0.11, 95% CI: 0.02-0.84, p = 0.03), and HLA mismatching (HR 0.80, 95% CI: 0.67-0.97, p = 0.02) were significantly associated with the development of PTLD. Patient survival was significantly decreased in patients with PTLD, with a one-, three-, and five-yr survival of 91%, 76%, and 70%, compared with 97%, 93%, and 88% in patients without PTLD (p < 0.001). PTLD is an uncommon but potentially lethal complication following pancreas transplantation. Patients with the risk factors identified should be monitored closely for the development of PTLD.

Cancer risk with alemtuzumab following kidney transplantation.

Alemtuzumab has been employed for induction therapy in kidney transplantation with low rates of acute rejection and excellent graft and patient survival. Antibody induction therapy has been linked to increased vulnerability to cancer. Data regarding malignancy rates with alemtuzumab are limited. We studied 1350 kidney transplant recipients (between 2001 and 2009) at the University of Pittsburgh Starzl Transplant Institute, for post-transplant de novo and recurrent malignancy, excluding non-melanoma skin cancer, among patients receiving alemtuzumab, thymoglobulin, and no induction therapies. Of the 1350 patients, 1002 (74.2%) received alemtuzumab, 205 (15.2%) received thymoglobulin, and 122 (9%) received no induction therapy. After excluding cancers occurring within 60 d post-transplantation, 43 (3.25%) malignancies were observed during a median follow-up time of 4.0 yr. The incidence of malignancy was 5.4% (1.09 per 100 patient-years [PY]) with thymoglobulin, 2.8% (0.74 per 100 PY) with alemtuzumab, and 3.3% (0.66 per 100 PY) with no induction (across all groups; p = 0.2342, thymoglobulin vs. alemtuzumab; p = 0.008). Thus, with the exception of non-melanoma skin cancer which we did not evaluate, alemtuzumab induction was not associated with increased cancer incidence post-kidney transplantation when compared to no induction therapy and was associated with lower cancer incidence when compared to thymoglobulin.

Bias in reporting of end points of efficacy and toxicity in randomized, clinical trials for women with breast cancer.

BACKGROUND: Phase III randomized, clinical trials (RCTs) assess clinically important differences in end points that reflect benefit to patients. Here, we evaluate the quality of reporting of the primary end point (PE) and of toxicity in RCTs for breast cancer. METHODS: PUBMED was searched from 1995 to 2011 to identify RCTs for breast cancer. Bias in the reporting of the PE and of toxicity was assessed using pre-designed algorithms. Associations of bias with the Journal Impact Factor (JIF), changes in the PE compared with information in ClinicalTrials.gov and funding source were evaluated. RESULTS: Of 164 included trials, 33% showed bias in reporting of the PE and 67% in the reporting of toxicity. The PE was more likely to be reported in the concluding statement of the abstract when significant differences favoring the experimental arm were shown; 59% of 92 trials with a negative PE used secondary end points to suggest benefit of experimental therapy. Only 32% of articles indicated the frequency of grade 3 and 4 toxicities in the abstract. A positive PE was associated with under-reporting of toxicity. CONCLUSION: Bias in reporting of outcome is common for studies with negative PEs. Reporting of toxicity is poor, especially for studies with positive PEs.

Pharmacokinetics of low-dose cidofovir in kidney transplant recipients with BK virus infection.

BACKGROUND: BK virus (BKV) infection in kidney transplant recipients is associated with progressive graft dysfunction and graft loss. Cidofovir, an antiviral agent with known nephrotoxicity, has been used in low doses to treat BKV infections. However, the systemic exposure and disposition of the low-dose cidofovir regimen are not known in kidney transplant recipients. METHODS: We investigated the pharmacokinetics (PK) of low-dose cidofovir (0.24 - 0.62 mg/kg) both without and with oral probenecid in 9 transplant patients with persistent BK viremia without nephropathy in a crossover design. RESULTS: The mean estimated glomerular filtration rate (eGFR) of the study participants was 46.2 mL/min/1.73 m(2) (range: 17-75 mL/min/1.73 m(2) ). The contribution of active renal secretion to cidofovir total body clearance was assessed by evaluating the effect of probenecid on cidofovir PK. Maximum cidofovir plasma concentrations, which averaged approximately 1 µg/mL, were significantly below the 36 µg/mL 50% effective concentration in vitro for cidofovir against BKV. The plasma concentration of cidofovir declined with an overall disposition half-life of 5.1 ± 3.5 and 5.3 ± 2.9 h in the absence and in the presence of probenecid, respectively (P > 0.05). CONCLUSIONS: Cidofovir clearance and eGFR were linearly related irrespective of probenecid administration (r(2) = 0.8 without probenecid; r(2) = 0.7 with probenecid). This relationship allows for the prediction of systemic cidofovir exposure in individual patients and may be utilized to evaluate exposure-response relationships to optimize the cidofovir dosing regimen for BKV infection.

Mucormycosis in a liver allograft: salvage re-transplantation and targeted immunosuppressive management.

Zygomycetes infection is associated with a high mortality in transplant populations. We describe a child with liver allograft Rhizopus oryzae infection who was salvaged by liver re-transplantation. A 10-year-old child presented with anastomotic bile leak that was repaired. A combined antibiotics and voriconazole regimen was introduced for Escherichia coli and Candida krusei growth in the peritoneal fluid. Despite broad antibiotic and antifungal coverage, the patient continued to have an ongoing infection. A follow-up computed tomography scan 8 weeks later showed 2 liver abscesses infiltrating the stomach and the diaphragm, with splenic infarcts and pericardial effusion. Aspirated samples from the liver abscess and the pericardial fluid revealed R. oryzae. Immunosuppression was discontinued and an antifungal regimen combining amphotericin B, posaconazole, and caspofungin was introduced. After 3 weeks of treatment with control of the systemic signs of infection, a positron emission tomography showed the fluorescence stain limited to the liver. With infection confined to the liver, the child underwent liver re-transplantation, splenectomy, and partial gastrectomy. Immunosuppression was reintroduced with recovery of the immune response observed by the CD4 cells adenosine triphophate release (Cylex(™) ImmuKnow(®) assay) and posaconazole was continued for another year. At 3-year follow-up, the child maintained normal graft function. We conclude that discontinuation of immunosuppression combined with a modern antifungal regimen may allow salvage re-transplantation in patients with liver mucormycosis.

Pneumocystis pneumonia in solid organ transplant recipients: not yet an infection of the past.

BACKGROUND: Solid organ transplant (SOT) recipients are at risk for Pneumocystis pneumonia (PCP), especially in the first year post transplant. Although trimethoprim-sulfamethoxazole (TMP-SMX) prophylaxis substantially decreases this risk, there is little data or consensus on optimal duration of prophylaxis. Consequently, there is lack of standardization of prophylaxis duration (3 months to lifelong, depending on organ group) in SOT programs. METHODS: We performed a retrospective chart review of all cases of confirmed PCP, in adult kidney, pancreas, liver, and lung transplant recipients from 2001 to 2011 in our SOT program. RESULTS: Of 1241 patients followed in our clinic (657 kidney, 44 kidney/pancreas, 436 liver, and 104 lung or heart/lung), a total of 14 PCP cases were identified in 2 kidney, 1 kidney/pancreas, 5 liver, 5 single lung, and 1 heart/lung transplant recipient. At the time of PCP diagnosis, immunosuppression in most cases consisted of prednisone, tacrolimus, and mycophenolate mofetil (79% of patients), and 53% had previously received TMP-SMX for prophylaxis. None were on PCP prophylaxis at the time of illness onset. PCP occurred early in all 5 liver transplant recipients and in 1 kidney transplant recipient, none of whom had ever received prophylaxis (17-204 days post transplant). Of those who had received 6 months of prophylaxis (1 kidney, 1 kidney/pancreas), PCP occurred at 846 and 4778 days, respectively. Late onset PCP occurred in lung recipients who had received 12 months of prophylaxis (lung 645-1414 days, heart/lung 1583 days post transplant). Five patients had experienced acute rejection and 6 patients had cytomegalovirus (CMV) viremia on average 59 and 204 days preceding PCP, respectively. Three deaths (1 liver, 2 lung) were thought to be directly related to complications of PCP. CONCLUSION: Our experience with late PCP cases in lung transplant recipients receiving only 1 year of prophylaxis lends support to prolonged PCP prophylaxis in this group. Given the number of patients who had experienced an acute rejection episode or CMV disease preceding PCP in non-lung SOT recipients, consideration should be given to re-institution of PCP prophylaxis for a period of time after these events in kidney, kidney/pancreas, and liver transplant recipients.

The Banff 2009 Working Proposal for polyomavirus nephropathy: a critical evaluation of its utility as a determinant of clinical outcome.

Clinical outcome in BK virus nephropathy (BKVN) was examined in relation to clinical and histologic parameters with reference to the Banff Working Proposal 2009, which emphasizes tubular injury and viral load. Seventy one patients were evaluated in three eras: (i) Era-I: No BKV PCR performed (n = 36), (ii) Era-II: PCR performed for rising creatinine (n = 24) and (iii) Era III: PCR performed for routine screening (n = 11). Six of seventy-one (8.4%) patients were classified as Class A, 46/71 (64.8%) as Class B and 19/71 (26.8%) as Class C. Banff class A never occurred in Era-I. It is a heterogeneous class that includes biopsies with inflammation that have hitherto been included in Class B. Higher inflammation, but not tubular injury, nor histologic viral load correlated with worse creatinine at 3 months. On long-term follow-up, class C associated with graft loss (hazard ratio 2.45, p = 0.03). Clearance of viremia was associated with better graft survival at 5 years (46.0% vs. 25.0%). Viruria clearance was infrequent (15.6%). In conclusion, the clinical utility of the Banff Working Proposal 2009 derives from scoring of fibrosis and not extent of tubular injury or viral cytopathic effect. The proposal is not superior to existing schemas that include assessment of inflammation, which is a well-known prognostic marker in other renal allograft diseases.

Impact of genomic sequence variability on quantitative PCR assays for diagnosis of polyomavirus BK infection.

Knowledge of polyomavirus BK (BKV) genomic diversity has greatly expanded. The implications of BKV DNA sequence variation for the performance of molecular diagnostic assays is not well studied. We analyzed 184 publically available VP-1 sequences encompassing the BKV genomic region targeted by an in-house quantitative hydrolysis probe-based PCR assay. A perfect match with the PCR primers and probe was seen in 81 sequences. One Dun and 13 variant prototype oligonucleotides were synthesized as artificial targets to determine how they affected the performance of PCR. The sensitivity of detection of BKV in the PCR assay was a function of the viral genotype. Prototype 1 (BKV Dun) could be reliably detected at concentrations as low as 10 copies/µl. However, consistent detection of all BKV variants was possible only at concentrations of 10,000 copies/µl or higher. For BKV prototypes with 2 or more mismatches (representing genotype IV, genotype II, and genotype 1c strains), the calculated viral loads were 0.57 to 3.26% of the expected values. In conclusion, variant BKV strains lower the sensitivity of detection and may have a substantial effect on quantitation of the viral load. Physicians need to be cognizant of these effects when interpreting the results of quantitative PCR testing in transplant recipients, particularly if there is a discrepancy between the clinical impression and the measured viral load.

Donor-transmitted malignancies in organ transplantation: assessment of clinical risk.

The continuing organ shortage requires evaluation of all potential donors, including those with malignant disease. In the United States, no organized approach to assessment of risk of donor tumor transmission exists, and organs from such donors are often discarded. The ad hoc Disease Transmission Advisory Committee (DTAC) of the Organ Procurement and Transplantation Network/United Network for Organ Sharing (OPTN/UNOS) formed an ad hoc Malignancy Subcommittee to advise on this subject. The Subcommittee reviewed the largely anecdotal literature and held discussions to generate a framework to approach risk evaluation in this circumstance. Six levels of risk developed by consensus. Suggested approach to donor utilization is given for each category, recognizing the primacy of individual clinical judgment and often emergent clinical circumstances. Categories are populated with specific tumors based on available data, including active or historical cancer. Benign tumors are considered in relation to risk of malignant transformation. Specific attention is paid to potential use of kidneys harboring small solitary renal cell carcinomas, and to patients with central nervous system tumors. This resource document is tailored to clinical practice in the United States and should aid clinical decision making in the difficult circumstance of an organ donor with potential or proven neoplasia.

Higher Volume at Time of Breast Conserving Surgery Reduces Re-Excision in DCIS.

Purpose. The purpose of this study was to compare the surgical and pathological variables which impact rate of re-excision following breast conserving therapy (BCS) with or without concurrent additional margin excision (AM). Methods. The pathology database was queried for all patients with DCIS from January 2004 to September 2008. Pathologic assessment included volume of excision, subtype, size, distance from margin, grade, necrosis, multifocality, calcifications, and ER/PR status. Results. 405 cases were identified and 201 underwent BCS, 151-BCS-AM, and 53-mastectomy. Among the 201 BCS patients, 190 underwent re-excision for close or involved margins. 129 of these were treated with BCS and 61 with BCS-AM (P < .0001). The incidence of residual DCIS in the re-excision specimens was 32% (n = 65) for BCS and 22% (n = 33) for BCS-AM (P < .05). For both the BCS and the BCS-AM cohorts, volume of tissue excised is inversely correlated to the rate of re-excision (P = .0284). Multifocality (P = .0002) and ER status (P = .0382) were also significant predictors for rate of re-excision and variation in surgical technique was insignificant. Conclusions. The rate of positive margins, re-excision, and residual disease was significantly higher in patients with lower volume of excision. The performance of concurrent additional margin excision increases the efficacy of BCS for DCIS.

Coupling temperature sensing and development: Hsp90 regulates morphogenetic signalling in Candida albicans.

Hsp90 is environmentally contingent molecular chaperone that influences the form and function of diverse signal transducers. Here we discuss our recent findings that Hsp90 regulates the morphogenetic transition from yeast to filamentous forms required for virulence of the most prevalent fungal pathogen of humans, Candida albicans, and does so via cAMP-PKA signalling. This transition is normally regulated by environmental cues that are contingent upon elevated temperature to relieve Hsp90-mediated repression of the morphogenetic program. Intriguingly, Hsp90 inhibition induces filamentation independent of the canonical PKA transcription factor Efg1, in striking similarity to a select set of morphogenetic stimuli. Further investigation will determine the downstream transcription factors through which Hsp90 regulates morphogenesis and the precise mechanism of Hsp90's interaction with the cAMP-PKA pathway. C. albicans is one of many fungal species that undergo a morphological transition in a temperature-dependent manner, thus Hsp90's capacity to govern this key developmental program may provide insight into morphogenesis of diverse organisms.

A critical appraisal of methods to grade transplant glomerulitis in renal allograft biopsies.

Transplant glomerulitis is an increasingly recognized lesion in renal transplant biopsies. To develop a refined grading system, we defined glomerulitis by the presence of ≥5 leukocytes/glomerulus and evaluated 111 biopsies using three different grading systems: (i) percentage of glomerular involvement, (ii) peak inflammation in the most severely affected glomerulus and (iii) presence/absence of endocapillary occlusion by inflammatory cells. Endocapillary occlusion had no impact on graft survival, but was associated with increased serum creatinine, proteinuria and subsequent transplant glomerulopathy. Grading based on either percent or peak glomerular involvement correlated with graft failure and peritubular capillaritis. However, the percent glomerular involvement method had the additional advantage of displaying associations with: concurrent proteinuria, focal or diffuse immunoperoxidase peritubular capillary C4d staining, 1-year postbiopsy serum creatinine, subsequent detection of donor-specific antibody and development of transplant glomerulopathy. Patients with >75% glomerular involvement also revealed persistent high-grade glomerulitis on follow-up biopsies despite antirejection treatment. In conclusion, grading of glomerulitis is a meaningful exercise, and a quantification system based on percentage of glomerular involvement shows the most robust associations with clinical parameters and prognosis.

Recipient tissue factor expression is associated with consumptive coagulopathy in pig-to-primate kidney xenotransplantation.

Consumptive coagulopathy (CC) remains a challenge in pig-to-primate organ xenotransplantation (Tx). This study investigated the role of tissue factor (TF) expression on circulating platelets and peripheral blood mononuclear cells (PBMCs). Baboons (n = 9) received a kidney graft from pigs that were either wild-type (n = 2), alpha1,3-galactosyltransferase gene-knockout (GT-KO; n = 1) or GT-KO and transgenic for the complement-regulatory protein, CD46 (GT-KO/CD46, n = 6). In the baboon where the graft developed hyperacute rejection (n = 1), the platelets and PBMCs expressed TF within 4 h of Tx. In the remaining baboons, TF was detected on platelets on post-Tx day 1. Subsequently, platelet-leukocyte aggregation developed with formation of thrombin. In the six baboons with CC, TF was not detected on baboon PBMCs until CC was beginning to develop. Graft histopathology showed fibrin deposition and platelet aggregation (n = 6), but with only minor or no features indicating a humoral immune response (n = 3), and no macrophage, B or T cell infiltration (n = 6). Activation of platelets to express TF was associated with the initiation of CC, whereas TF expression on PBMCs was concomitant with the onset of CC, often in the relative absence of features of acute humoral xenograft rejection. Prevention of recipient platelet activation may be crucial for successful pig-to-primate kidney Tx.