Porcine-derived pancreatic enzyme replacement therapy may be linked to chronic hepatitis E virus infection in cystic fibrosis lung transplant recipients

OBJECTIVES

In high-income countries hepatitis E virus (HEV) is an uncommonly diagnosed porcine-derived zoonoses. After identifying disproportionate chronic HEV infections in persons with cystic fibrosis (pwCF) postlung transplant, we sought to understand its epidemiology and potential drivers.

DESIGN

All pwCF post-transplant attending our regional CF centre were screened for HEV. HEV prevalence was compared against non-transplanted pwCF and with all persons screened for suspected HEV infection from 2016 to 2022 in Alberta, Canada. Those with chronic HEV infection underwent genomic sequencing and phylogenetic analysis. Owing to their swine derivation, independently sourced pancreatic enzyme replacement therapy (PERT) capsules were screened for HEV.

RESULTS

HEV seropositivity was similar between transplanted and non-transplanted pwCF (6/29 (21%) vs 16/83 (19%); p=0.89). Relative to all other Albertans investigated for HEV as a cause of hepatitis (n=115/1079, 10.7%), pwCF had a twofold higher seropositivity relative risk and this was four times higher than the Canadian average. Only three chronic HEV infection cases were identified in all of Alberta, all in CF lung transplant recipients (n=3/29, 10.3%). Phylogenetics confirmed cases were unrelated porcine-derived HEV genotype 3a. Ninety-one per cent of pwCF were taking PERT (median 8760 capsules/person/year). HEV RNA was detected by RT-qPCR in 44% (47/107) of PERT capsules, and sequences clustered with chronic HEV cases.

CONCLUSION

PwCF had disproportionate rates of HEV seropositivity, regardless of transplant status. Chronic HEV infection was evident only in CF transplant recipients. HEV may represent a significant risk for pwCF, particularly post-transplant. Studies to assess HEV incidence and prevalence in pwCF, and potential role of PERT are required.

The Impact of Colonization by Multi Drug Resistant Bacteria on Graft Survival, Risk of Infection, and Mortality in Recipients of Solid Organ Transplant: Systematic Review and Meta-analysis

BACKGROUND

The Global increase in colonization by multidrug-resistant (MDR) bacteria poses a significant concern. The precise impact of MDR colonization in solid organ transplant recipients (SOTR) remains not well established.

OBJECTIVES

Assess the impact of MDR colonization on SOTR's mortality, infection, or graft-loss.

METHODS

.

DATA SOURCE

Data from PROSPERO, OVID Medline, Ovid EMBASE, Wiley Cochrane Library, ProQuest Dissertations, Theses Global, and SCOPUS, were systematically reviewed spanning from inception until March 20, 2023. The study protocol was registered with PROSPERO (CRD42022290011) and followed the PRISMA guidelines. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS, INTERVENTIONS, AND ASSESSMENT OF RISK OF BIAS: Cohorts and case-control studies that reported on adult SOTR colonized by Methicillin-resistant Staphylococcus-aureus (MRSA), Vancomycin-resistant Enterococci (VRE), Extended-spectrum beta-lactamase (ESBL) or carbapenem-resistant Enterobacteriaceae (CRE), or MDR-Pseudomonas, and compared to non-colonized, were included. Two reviewers assessed eligibility, conducted risk of bias evaluation using the Newcastle-Ottawa scale, and rated certainty of evidence using the GRADE approach.

METHODS OF DATA SYNTHESIS

We employed RevMan for a meta-analysis using random-effects models to compute pooled odds-ratios (OR) and 95% confidence-intervals (CI). Statistical heterogeneity was determined using the I2 statistic.

RESULTS

15,202 SOTR (33 cohort, 6 case-control studies) were included, where Liver transplant and VRE colonization (25 and 14 studies) were predominant. MDR colonization significantly increased post-transplant one-year mortality (OR= 2.35, 95%CI 1.63-3.38) and mixed-infections (OR=10.74, 95%CI 7.56-12.26) across transplant types (p<0.001 and I2= 58%), but no detected impact on graft-loss (p=0.41, I2= 0%). Subgroup analysis indicated a higher association between CRE or ESBL colonization with outcomes (CRE: death OR=3.94, mixed-infections OR=24.8; ESBL: mixed-infections OR=10.3, no mortality data) compared to MRSA (Death: OR=2.25; Mixed-infection: OR=7.75) or VRE colonization (Death: p=0.20, Mixed-infections: OR=5.71).

CONCLUSIONS

MDR colonization in SOTR, particularly CRE, is associated with increased mortality. Despite the low certainty of evidence, actions for preventing MDR colonization in transplant candidates are warranted.

Sexual and gender minority relevant policies in Canadian and United States organ and tissue donation and transplantation systems: An opportunity to improve equity and safety

Current policies in organ and tissue donation and transplantation (OTDT) systems in Canada and the United States unnecessarily restrict access to donation for sexual and gender minorities (SGMs) and pose safety risks to transplant recipients. We compare SGM-relevant policies between the Canadian and United States systems. Policy domains include the risk assessment of living and deceased organ and tissue donors, physical examination considerations, viral testing recommendations, and informed consent and communication. Identified gaps between current evidence and existing OTDT policies along with differences in SGM-relevant policies between systems, represent an opportunity for improvement. Specific recommendations for OTDT system policy revisions to achieve these goals include the development of behavior-based, gender-neutral risk assessment criteria, a reduction in current SGM no-sexual contact period requirements pending development of inclusive criteria, and destigmatization of sexual contact with people living with human immunodeficiency virus. OTDT systems should avoid rectal examinations to screen for evidence of receptive anal sex without consent and mandate routine nucleic acid amplification test screening for all donors. Transplant recipients must receive enhanced risk-to-benefit discussions regarding decisions to accept or decline an offer of an organ classified as increased risk. These recommendations will expand the donor pool, enhance equity for SGM people, and improve safety and outcomes for transplant recipients.

Systemic corticosteroids for outpatient respiratory viral infections in lung transplant recipients

INTRODUCTION

Respiratory viral infections (RVI) in lung transplant recipients (LTR) have variably been associated with rejection and chronic lung allograft dysfunction. Our center has used systemic corticosteroids to treat outpatient RVI in some cases, but evidence is limited. We reviewed all adult LTR diagnosed with outpatient RVI January 2017 to December 2019. The primary outcome was recovery of lung function (forced expiratory volume in 1 s [FEV1]) at next stable visit between 1 and 12 months postinfection, expressed as a ratio over stable preinfection FEV1 (FEV1 recovery ratio).

METHODS

We identified 100 adult LTR with outpatient RVI diagnoses eligible for study, 36% of whom received corticosteroids. We modelled the adjusted association between corticosteroid use and FEV1 recovery ratio using linear regression.

RESULTS

Steroid-treated patients had a lower FEV1 presentation ratio (0.92 vs. 1.04, p = .0070) and were more likely to have chronic lung allograft dysfunction at time of infection (25% vs. 5%, p = .0077). Mean FEV1 recovery ratio was 1.02 (SD 0.19) with no association with corticosteroid therapy via multivariable linear regression (p = .5888).

CONCLUSIONS

Steroid treatment was not associated with FEV1 recovery. This suggests corticosteroids may not have a role in the management of RVI in this population.

Evaluation and comparison of risk-based and universal prenatal HCV screening programs in Alberta, Canada

BACKGROUND & AIMS

Canadian clinical practice guidelines currently recommend risk-based screening for HCV in pregnant individuals. However, no provinces or territories have ever compared the effectiveness of risk-based vs. universal screening for the prenatal diagnosis of HCV. We aimed to evaluate and compare HCV screening programs after implementing a universal population-level pilot program among prenatal patients in Alberta, Canada.

METHODS

The Alberta Prenatal Screening Program for Select Communicable Diseases was amended to include universal HCV antibody screening. Cohorts of pregnant individuals screened for HCV through risk-based or universal programs were generated over 1-year periods. HCV screening rates and prevalence were analyzed and compared between cohorts to evaluate the effectiveness of screening methods. Social and demographic risk factors for HCV-positive individuals were compared between screening cohorts to identify which populations may be overlooked with risk-based guidelines.

RESULTS

HCV antibody screening rates were 11.9% and 99.9% among pregnant individuals in the risk-based and universal cohorts, respectively. HCV prevalence among the cohorts was 0.07% and 0.11% (difference = 0.04%, p = 0.032), with an average of 21 additional HCV-positive pregnant individuals identified annually with universal screening. HCV-positive pregnant patients diagnosed through universal screening were more likely to engage in high-risk sexual behaviours/sex work compared to those diagnosed through risk-based screening (47.6% vs. 12.5%, respectively p = 0.035), suggesting that these high-risk cases are being missed by risk-based screening.

CONCLUSIONS

Universal HCV screening diagnoses significantly higher numbers of pregnant individuals infected with HCV compared to risk-based screening. Universal HCV screening or amending risk-based guidelines to incorporate more proxy variables for risk factors should be considered to improve prenatal HCV screening guidelines in Canada and help achieve HCV elimination in the next decade.

IMPACT AND IMPLICATIONS

HCV is a bloodborne pathogen that can cause severe liver disease and be vertically transmitted from a mother to her baby during pregnancy. Pregnant individuals in Alberta are currently only tested for HCV if they disclose engaging in activities that put them at risk of acquiring the infection (risk-based screening). Using a population-wide universal prenatal HCV screening program, our work shows that testing based on patient disclosed risk alone leads to the significant underdiagnosis of HCV in pregnant individuals and suggests individuals engaging in sex work or risky sexual behaviours are being overlooked by the current risk-based program. Our outcomes represent the first province-wide study to evaluate and compare prenatal HCV risk-based and universal screening programs in Canada and provide evidence to support the update of prenatal HCV screening policies across the country and in similar jurisdictions.

Serologic follow-up of solid organ transplant recipients who received organs from donors with reactive syphilis tests: A retrospective cohort study

The increased procurement of organs from donors with risk factors for blood-borne diseases and the expanding syphilis epidemic have resulted in a growing number of organs transplanted from donors with reactive syphilis serology in our center. Based on guidelines, recipients typically receive therapy shortly after the transplant, but data on outcomes are limited. The primary objective of this study was to determine syphilis seroconversion rates at three months post-transplant in recipients of solid organs procured from donors with reactive syphilis serology. Organ donors and recipients were tested for syphilis antibody; positive results were confirmed with Treponema pallidum Particle Agglutination (TPPA). Eleven donors with reactive syphilis antibody donated organs to 25 syphilis negative recipients. Three recipients seroconverted at post-transplant month 3. All of them had received therapy shortly after transplant. TPPA was negative in all 3. Despite post-transplant treatment, 3 of 25 (12%) syphilis negative recipients of organs from syphilis positive donors seroconverted at 3 months. All remained TPPA negative possibly reflecting passive antibody transfer or differing test sensitivity to low level treponemal antibodies. Further studies are needed to assess optimal syphilis transmission prevention strategies and follow up recipient testing in organ transplantation.

2104. Cytomegalovirus DNAemia Patterns in Mismatched Solid Organ Transplant Recipients: A Retrospective Cohort Study

Background

Cytomegalovirus (CMV) seronegative solid organ transplant (SOT) recipients who receive grafts from seropositive donors are at high risk of CMV disease. Antiviral prophylaxis in usually given to this group of patients to prevent illness. Patients are still at risk of CMV after completion of prophylaxis. Surveillance after prophylaxis is used in some centres to prevent late CMV disease, but there is scant information of its efficacy. Finally, little is known on CMV kinetics post-prophylaxis in high-risk patients.

Methods

This was a retrospective cohort study including adult CMV mismatch (D+/R-) SOT recipients between 2003-2017 at a multiorgan transplant center in Canada. Post-prophylaxis CMV kinetics were classified into 3 patterns of DNAemia: no DNAemia, single episode of DNAemia and recurrent episodes of DNAemia. We calculated the cumulative incidence of each DNAemia pattern. We also compared 5-year mortality according to CMV DNAemia pattern by Cox-regression analysis. Patients were monitored weekly with CMV viral load for 12 weeks after completion of prophylaxis.

Results

Two-hundred and forty-five transplant patients were included (Table 1). Median follow up time was 9.2 years (7-12.7). Death occurred in 32 patients during the study period, the median time to death was 7.3 years (4.9-10). Pattern 1 (no CMV DNAemia) occurred in 38%, 27% had a single episode (pattern 2) of CMV DNAemia and 35% had recurrent (pattern 3) CMV DNAemia. Median time to DNAemia was 186 days. The first episode occurred at a significantly shorter interval in liver recipients when compared to non-liver recipients, 158 days (134-217) vs. 208 days (149-315), p=0.0164. Recurrent CMV DNAemia (pattern 3) was significantly more common in lung transplant recipients compared to non-lung transplant recipients. (63% vs. 32% p=0.003).

Mortality at 5 years was statistically not different between CMV patterns, adjusted by organ transplanted and age (Pattern 1 reference; pattern 2 HR 1.484 [0.24-9. Table 1.

872. Voriconazole Therapeutic Drug Monitoring (TDM): How Common is Autoinduction?

Background

Therapeutic drug monitor (TDM) guided optimized dosing of Voriconazole allows optimal drug exposure in the management of mold infection (MI). In addition to already known nuances in pharmacokinetics such as CYP2C19 genetic polymorphism and the role of drug interactions both necessitating TDM, case reports have suggested that auto-induction may occur after initially achieving a therapeutic level. We assessed whether the levels of Voriconazole can change over time and become subtherapeutic due to auto-induction.

Methods

We prospectively enrolled, adults ≥ 18 y.o of age, on Voriconazole for the treatment of MI at the University Of Alberta Hospital. After achieving an initial therapeutic margin, (1–5.5mg/l), we monitored Voriconazole levels twice a month, using high-performance liquid chromatography, until discontinuation or at 12 weeks of therapy. We calculated the incidence of Voriconazole sub-therapeutic concentrations (auto-induction) defined as drop of Voriconazole level below one, with previous concentrations between the therapeutic margins of 1–5.5 mg/L. Adjustment of Voriconazole dosing in case of auto-induction was at the discretion of the treating physician. The excess Voriconazole dose adjustment was calculated in patients where dosing was increased.

Results

Between January 2021 and April 2022, we enrolled 12 patients. Median age (IQR) was 62 (52–73), and 25 % were female. Patient characteristics are in table 1. Auto-induction was observed in 6/10 (60%) who completed 12 weeks follow up blood work. Median time to auto-induction was of 46 days (39–55). Voriconazole dosing was increased in 4/6 patients with auto-induction. Of the four patients with dose adjustment, the cumulative Voriconazole dose was 13% higher than expected, which correspond to 5,300 mg excess Voriconazole per patient to maintain therapeutic levels.

Conclusion

Auto-induction is common in patients treated with Voriconazole. Future studies are needed to assess if undetected auto-induction affects outcomes.

Funding: AVIR Pharma.

Disclosures

Carlos Cervera, Associate Professor, Astra-Zeneca: Advisor/Consultant|AVIR Pharma: Grant/Research Support|AVIR Pharma: Honoraria|Lilly: Advisor/Consultant|Merck: Advisor/Consultant|Merck: Grant/Research Support|Merck: Honoraria|Sunovion: Advisor/Consultant|Takeda: Advisor/Consultant|Takeda: Honoraria|VerityPharma: Advisor/Consultant Dima Kabbani, MD, MSc, AVIR Pharma: Grant/Research Support|AVIR Pharma: Honoraria|GSK: Honoraria|Merck: Grant/Research Support.

2111. Impact of Colonization by Multi Drug Resistant Bacteria on Graft Survival, Risk of Infection, and Mortality in Recipients of Solid Organ Transplant: Systematic Review and Meta-analysis

Background

Colonization with multi-drug resistant bacteria (MDR) in solid organ transplant (SOT) recipients increases the risk of post-transplant bacterial infection. MDR colonization impact on graft survival and mortality is not well established.

Methods

A search was executed by an expert librarian on PROSPERO, OVID Medline, Ovid EMBASE, Wiley Cochrane Library, ProQuest dissertations and Theses Global and SCOPUS, from inception until October 26, 2021. Adult SOT colonized with Methicillin resistant Staphylococcus aureus (MRSA), Vancomycin-resistant Enterococci (VRE), Extended-spectrum beta-lactamase (ESBL) or AmpC producing bacteria, carbapenem resistant Enterobacteriaceae (CRE), or MDR Pseudomonas were included and compared to non-colonized SOT. Pairs of reviewers screened abstracts and full studies for inclusion, and extracted data independently. We used RevMan to conduct a meta-analysis using random effects models to calculate the pooled risk ratio (RR) with 95% confidence interval (CI) for the incidence of infection, mortality, and graft failure. Statistical heterogeneity was determined using the I² statistic. Figure-1

PRISMA chart, systemic review and metanalysis on Impact Of Colonization By Multi Drug Resistant Bacteria on Graft Survival, Risk of Infection, and Mortality in Recipients of Solid Organ Transplant.

Results

59 articles spanning from 1989 to 2021 were included (Figure-1). Liver transplant (43 studies) and VRE colonization (17 studies) were the most common organ and MDR pathogen. MDR surveillance was performed by culture (71%) and PCR (6.7%). In liver transplant recipients, VRE and MRSA colonization were associated with increased infection risk, but not mortality (VRE infection: RR= 2.40 (95%CI 1.54-3.73; p< 0.001), I²= 66%; VRE mortality: RR= 1.64 (95%CI 0.88-3.05; p=0.12), I²= 44%; MRSA infection: RR= 4.07 (95%CI 2.66-6.24; p< 0.001), I²= 59%; MRSA mortality RR=1.47 (95%CI 0.79-2.76; p=0.23), I²= 35%). ESBL and CRE colonization were associated with increased risk of infection (ESBL: RR=9.87 (6.12-15.93); p< 0.001), I²=13%; CRE: RR= 13.64 (95%CI 5.73-32.47); p< 0.001), I²= 66%). CRE colonization was associated with increased mortality, RR=5.79 (95% CI 1.80-18.63; p=0.003), I²=0%.

Conclusion

While colonization with MRSA and VRE in liver transplant was not associated with increase mortality, CRE colonization was associated with almost 6-fold increased risk of death. These data should be taken into account when stratifying the risk of transplant.

Disclosures

Carlos Cervera, Associate Professor, Astra-Zeneca: Advisor/Consultant|AVIR Pharma: Grant/Research Support|AVIR Pharma: Honoraria|Lilly: Advisor/Consultant|Merck: Advisor/Consultant|Merck: Grant/Research Support|Merck: Honoraria|Sunovion: Advisor/Consultant|Takeda: Advisor/Consultant|Takeda: Honoraria|VerityPharma: Advisor/Consultant Dima Kabbani, MD, MSc, AVIR Pharma: Grant/Research Support|AVIR Pharma: Honoraria|GSK: Honoraria|Merck: Grant/Research Support.

Immune-Based Therapy for Hospitalized Patients With COVID-19 and Risk of Secondary Infections: A Systematic Review and Meta-analysis

Background

Immune-based therapies are standard-of-care treatment for coronavirus disease 2019 (COVID-19) patients requiring hospitalization. However, safety concerns related to the potential risk of secondary infections may limit their use.

Methods

We searched OVID Medline, Ovid EMBASE, SCOPUS, Cochrane Library, clinicaltrials.gov, and PROSPERO in October 2020 and updated the search in November 2021. We included randomized controlled trials (RCTs). Pairs of reviewers screened abstracts and full studies and extracted data in an independent manner. We used RevMan to conduct a meta-analysis using random-effects models to calculate the pooled risk ratio (RR) and 95% CI for the incidence of infection. Statistical heterogeneity was determined using the I ² statistic. We assessed risk of bias for all studies and rated the certainty of evidence using the Grading of Recommendations Assessment, Development, and Evaluation methodology. We conducted a meta-regression using the R package to meta-explore whether age, sex, and invasive mechanical ventilation modified risk of infection with immune-based therapies. The protocol is registered with PROSPERO (CRD42021229406).

Results

This was a meta-analysis of 37 RCTs including 32 621 participants (mean age, 60 years; 64% male). The use of immune-based therapy for COVID-19 conferred mild protection for the occurrence of secondary infections (711/15 721, 4.5%, vs 616/16 900, 3.6%; RR, 0.82; 95% CI, 0.71-0.95; P = .008; I ² = 28%). A subgroup analysis did not identify any subgroup effect by type of immune-based therapies (P = .85). A meta-regression revealed no impact of age, sex, or mechanical ventilation on the effect of immune-based therapies on risk of infection.

Conclusions

We identified moderate-certainty evidence that the use of immune-based therapies in COVID-19 requiring hospitalization does not increase the risk of secondary infections.

Nationwide retrospective study of hepatitis B virological response and liver stiffness improvement in 465 patients on nucleos(t)ide analogue

BACKGROUND

Hepatitis B virus (HBV) nucleos(t)ide analog (NA) therapy reduces liver disease but requires prolonged therapy to achieve hepatitis B surface antigen (HBsAg) loss. There is limited North American real-world data using non-invasive tools for fibrosis assessment and few have compared 1^st generation NA or lamivudine (LAM) to tenofovir disoproxil fumarate (TDF).

AIM

To assess impact of NA on virological response and fibrosis regression using liver stiffness measurement (LSM) (i.e., FibroScan^®).

METHODS

Retrospective, observational cohort study from the Canadian HBV Network. Data collected included demographics, NA, HBV DNA, alanine aminotransferase (ALT), and LSM. Patients were HBV monoinfected patients, treatment naïve, and received 1 NA with minimum 1 year follow-up.

RESULTS

In 465 (median 49 years, 37% female, 35% hepatitis B e antigen⁺ at baseline, 84% Asian, 6% White, and 9% Black). Percentage of 64 (n = 299) received TDF and 166 were LAM-treated with similar median duration of 3.9 and 3.7 years, respectively. The mean baseline LSM was 11.2 kPa (TDF) vs 8.3 kPa (LAM) (P = 0.003). At 5-year follow-up, the mean LSM was 7.0 kPa in TDF vs 6.7 kPa in LAM (P = 0.83). There was a significant difference in fibrosis regression between groups (i.e., mean -4.2 kPa change in TDF and -1.6 kPa in LAM, P < 0.05). The last available data on treatment showed that all had normal ALT, but more TDF patients were virologically suppressed (< 10 IU/mL) (n = 170/190, 89%) vs LAM-treated (n = 35/58, 60%) (P < 0.05). None cleared HBsAg.

CONCLUSION

In this real-world North American study, approximately 5 years of NA achieves liver fibrosis regression rarely leads to HBsAg loss.

A217 TREATMENT ADHERENCE OF CHRONIC HEPATITIS B PATIENTS WITH HEPATOCELLULAR CARCINOMA FROM THE CANHEPB NETWORK

Background

Chronic hepatitis B (CHB) is the most common cause of hepatocellular carcinoma (HCC) worldwide.

Aims

The primary aim of this study is to explore the degree of treatment adherence to the American Association For The Study of Liver Disease (AASLD) HCC treatment guidelines for patients with CHB-HCC.

Methods

This is a retrospective, cross-sectional study of available data (2005–2020) in patients mono-infected with CHB collected from the Canadian HBV Network; a national consortium across 8 Canadian provinces. We analyzed data using descriptive statistics along with parametric and nonparametric statistical methods with a significance level of p < 0.05.

Results

Of the 6500 patients, 132 (2.0%) patients met inclusion criteria. The median age was 64 (IQR: 53.5- 71.5) with 101 (76%) being male. The median ALT was 40 (IQR: 26–59.5) and the median tumor number was 1(IQR: 1- 2) with a median tumor size of 2.6 cm (IQR: 1.9- 4.5). 98 (74.5%) patients were HBeAg negative with a median viral load of 3.8 logs (IQR 1.9 – 5.8). 58 (43%) patients had cirrhosis at diagnosis. 36% of patients were diagnosed with HCC on their first screening imaging whereas 39% were found to have HCC on repeated surveillance imaging. 116 (87.9%) were on treatment at the time of diagnosis or after (70 (60.3%) NA and 46 (39%) Combination therapy with double NA or NA plus interferon). Out of the 132 patients, BCLC stage 0, A, B, and C represented 30 (23%), 42 (32%), 17 (13%), and 5 (4%) patients, respectively, with 38 (28%) patients with unknown BCLC stage. The overall adherence to AASLD guidelines was 61%. The HCC treatment adherence rate for patients with BCLC stage 0, A, B were 63%, 97.5%, and 23.5%, respectively. BCLC stages C and D did not have a sufficient sample size for analysis. The adherence rate ranged from 53% (Eastern Canada) to 71% (Western Canada) across Canada.

Conclusions

In this retrospective nationwide cohort study of patients with CHB-related HCC, the overall treatment adherence rate to AASLD guidelines was low with notable regional differences. Further analysis will determine the cause of regional differences.

Funding Agencies

None

117. How Does Antimicrobial Stewardship Provider Role Affect Prospective Audit and Feedback Acceptance by the Attending Physician?

Background

Antimicrobial stewardship (AMS) teams are commonly multidisciplinary. The effect of AMS provider role on prospective audit and feedback (PAF) acceptance has previously been investigated with mixed results. PAF of restricted antimicrobials (carbapenems, linezolid, daptomycin, and tigecycline) in adult inpatients at our large Canadian academic centre has been performed since 2018. Actionable feedback is communicated via chart note plus one of a phone call, direct message, or in-person discussion with the most responsible physician of the attending team in order to optimize the prescription if deemed necessary. The objective of this study was to assess the effect of AMS provider role on PAF acceptance.

Methods

A 3 year retrospective review of all PAF events was undertaken. All audited prescriptions were included. Logistic regression was used to determine odds ratios for acceptance for individual AMS provider roles of pharmacist, physician, and supervised post-graduate physician trainee.

Results

Out of 1896 prescriptions audited, actionable feedback was provided to the most responsible physician in 731 (39%) cases. 677/731 (93%) of audited antibiotics were carbapenems. The overall acceptance rate was 82% (598/731). Acceptance rate and odds of acceptance based on AMS provider role were as follows: pharmacist alone 171/208 (82%), OR 1.04, 95% CI 0.70-1.59, physician alone 141/160 (88%), OR 1.85, 95% CI 1.12-3.20, pharmacist-physician duo 211/268 (79%), OR 0.73, 95% CI 0.50-1.07, and supervised post-graduate physician trainee 75/95 (79%), OR 0.81, 95% CI 0.48-1.41.

Conclusion

The overall acceptance rate was high. There was a higher odds of acceptance if an AMS physician was providing PAF alone, highlighting the importance of physician involvement.

Disclosures

Dima Kabbani, MD, AVIR Pharma (Grant/Research Support, Other Financial or Material Support, Speaker)Edesa Biotech (Scientific Research Study Investigator)Merck (Scientific Research Study Investigator)

Cytomegalovirus transmission in mismatched solid organ transplant recipients: Are factors other than anti-viral prophylaxis at play?

Although antiviral prophylaxis has reduced cytomegalovirus (CMV) DNAemia and disease in seronegative solid organ transplant (SOT) recipients (R-) receiving seropositive donor organs (D+), its impact on CMV transmission is uncertain. Transmission, defined as CMV antigenemia/CMV DNAemia and/or seroconversion by year 2, and associated demographic risk factors were studied retrospectively in 428 D+/R- and 429 D-/R- patients receiving a SOT at our center. The cumulative transmission incidence was higher for lung (90.5%) and liver recipients (85.1%) than heart (72.7%), kidney (63.9%), and pancreas (56.2%) recipients (p < .001) and was significantly lower in living (50.1%) versus deceased donor (77.4%, p < .001) kidney recipients despite identical antiviral prophylaxis. In multivariate analysis, only allograft type predicted transmission risk (HR [CI] lung 1.609 [1.159, 2.234] and liver 1.644 [1.209, 2.234] vs kidney). For 53 D+ donating to >1 R- with adequate follow-up, 43 transmitted to all, three transmitted to none, and seven transmitted inconsistently with lungs and livers always transmitting but donor-matched heart, kidney or kidney-pancreas allografts sometimes not. Kidney pairs transmitted concordantly. CMV transmission risk is allograft-specific and unchanged despite antiviral prophylaxis. Tracking transmission and defining donor factors associated with transmission escape may provide novel opportunities for more targeted CMV prevention and improve outcome analysis in antiviral and vaccine trials.

Effectiveness and Renal Safety of Tenofovir Alafenamide Fumarate among Chronic Hepatitis B Patients: Real-World Study

Tenofovir alafenamide fumarate (TAF) has high plasma stability resulting in fewer renal adverse events compared to tenofovir disoproxil fumarate (TDF) in chronic hepatitis B (CHB) patients. We aimed to study the effectiveness and renal safety of TAF in a real-world setting, in patients with or without compromised kidney function. CHB patients (Nucleos(t)ide Analogue [NA]-naïve or experienced) who received TAF >1 year from 11 academic institutions as part of the Canadian Hepatitis B Network (CanHepB) were included. Kidney function was measured by estimated glomerular filtration rate (eGFR) as per Cockcroft-Gault. Patients were followed for up to 160 weeks. Of 176 patients receiving TAF, 143 switched from NA (88% TDF), and 33(19%) were NA naïve. Majority of NA-naïve patients (75%) achieved undetectable HBV DNA after one year of TAF treatment. Majority of patients with eGFR <60 mL/min who had renal deterioration during TDF (76%) reversed to eGFR increase after one year of TAF (p=0.009). Among patients with stage 2 chronic kidney disease (CKD) (eGFR 60-89), the estimated eGFR decline during TDF was halted after switching to TAF (p=0.09). NA-experienced patients with abnormal ALT before TAF showed a significant decline after switching to TAF: -0.005 [-0.006 - -0.004] log₁₀ ULN U/L/month, p<0.001). In CHB patients, TAF was safe, well-tolerated and effective in this real-world cohort. Switching to TAF led to improved kidney function, particularly in those with stage 2 CKD, which suggests that the indication for TAF in the guidelines could be extended to patients with an eGFR higher than 60 mL/min.

Mycobacteria: Selection of Transplant Candidates and Post-lung Transplant Outcomes

Mycobacterium is a large, clinically relevant bacterial genus made up of the agents of tuberculosis and leprosy and hundreds of species of saprophytic nontuberculous mycobacteria (NTM). Pathogenicity, clinical presentation, epidemiology, and antimicrobial susceptibilities are exceptionally diverse between species. Patients with end-stage lung disease and recipients of lung transplants are at a higher risk of developing NTM colonization and disease and of severe manifestations and outcomes of tuberculosis. Data from the past three decades have increased our knowledge of these infections in lung transplant recipients. Still, there are knowledge gaps to be addressed to further our understanding of risk factors and optimal treatments for mycobacterial infections in this population.

Atelectasis in primary graft dysfunction survivors after lung transplantation

BACKGROUND

Primary graft dysfunction (PGD) is an important contributor to early mortality in lung transplant recipients and is associated with impaired lung function. The radiographic sequelae of PGD on computed tomography (CT) have not been characterized.

METHODS

We studied adult double lung transplant recipients from 2010 to 2016 for whom protocol 3-month post-transplant CT scans were available. We assessed CTs for changes including pleural effusions, ground glass opacification, atelectasis, centrilobular nodularity, consolidation, interlobular septal thickening, air trapping and fibrosis, and their relationship to prior post-transplant PGD, future lung function, post-transplant baseline lung allograft dysfunction (BLAD), and chronic lung allograft dysfunction (CLAD).

RESULTS

Of 237 patients studied, 50 (21%) developed grade 3 PGD (PGD3) at 48 or 72 h. PGD3 was associated with increased interlobular septal thickening (p = .0389) and atelectasis (p = .0001) at 3 months, but only atelectasis remained associated after correction for multiple testing. Atelectasis severity was associated with lower peak forced expiratory volume in 1 s (FEV1) and increased risk of BLAD (p = .0014) but not with future CLAD onset (p = .7789).

CONCLUSIONS

Severe PGD was associated with atelectasis on 3-month post-transplant CT in our cohort. Atelectasis on routine CT may be an intermediary identifiable stage between PGD and future poor lung function.

Pneumocystis jirovecii: a review with a focus on prevention and treatment

Introduction: Pneumocystis jirovecii (PJ) is an opportunistic fungal pathogen that can cause severe pneumonia in immunocompromised hosts. Risk factors for Pneumocystis jirovecii pneumonia (PJP) include HIV, organ transplant, malignancy, certain inflammatory or rheumatologic conditions, and associated therapies and conditions that result in cell-mediated immune deficiency. Clinical signs of PJP are nonspecific and definitive diagnosis requires direct detection of the organism in lower respiratory secretions or tissue. First-line therapy for prophylaxis and treatment remains trimethoprim-sulfamethoxazole (TMP-SMX), though intolerance or allergy, and rarely treatment failure, may necessitate alternate therapeutics, such as dapsone, pentamidine, atovaquone, clindamycin, primaquine and most recently, echinocandins as adjunctive therapy. In people living with HIV (PLWH), adjunctive corticosteroid use in treatment has shown a mortality benefit.Areas covered: This review article covers the epidemiology, pathophysiology, diagnosis, microbiology, prophylaxis indications, prophylactic therapies, and treatments.Expert opinion: TMP-SMX has been first-line therapy for treating and preventing pneumocystis for decades. However, its adverse effects are not uncommon, particularly during treatment. Second-line therapies may be better tolerated, but often sacrifice efficacy. Echinocandins show some promise for new combination therapies; however, further studies are needed to define optimal antimicrobial therapy for PJP as well as the role of corticosteroids in those without HIV.

Distinct Hepatitis B and HIV co-infected populations in Canada

Due to shared modes of exposure, HIV-HBV co-infection is common worldwide. Increased knowledge of the demographic and clinical characteristics of the co-infected population will allow us to optimize our approach to management of both infections in clinical practice. The Canadian Hepatitis B Network Cohort was utilized to conduct a cross-sectional evaluation of the demographic, biochemical, fibrotic and treatment characteristics of HIV-HBV patients and a comparator HBV group. From a total of 5996 HBV-infected patients, 335 HIV-HBV patients were identified. HIV-HBV patients were characterized by older median age, higher male and lower Asian proportion, more advanced fibrosis and higher anti-HBV therapy use (91% vs. 30%) than the HBV-positive / HIV seronegative comparator group. A history of reported high-risk exposure activities (drug use, high-risk sexual contact) was more common in HIV-HBV patients. HIV-HBV patients with reported high-risk exposure activities had higher male proportion, more Caucasian ethnicity and higher prevalence of cirrhosis than HIV-HBV patients born in an endemic country. In the main cohort, age ≥60 years, male sex, elevated ALT, the presence of comorbidity and HCV seropositivity were independent predictors of significant fibrosis. HIV seropositivity was not an independent predictor of advanced fibrosis (adj OR 0.75 [95%CI: 0.34-1.67]). In conclusion, Canadian co-infected patients differed considerably from those with mono-infection. Furthermore, HIV-HBV-infected patients who report high-risk behaviours and those born in endemic countries represent two distinct subpopulations, which should be considered when engaging these patients in care.

Immunogenicity and Safety of the Adjuvanted Recombinant Zoster Vaccine in Chronically Immunosuppressed Adults Following Renal Transplant: A Phase 3, Randomized Clinical Trial

Background

The incidence of herpes zoster is up to 9 times higher in immunosuppressed solid organ transplant recipients than in the general population. We investigated the immunogenicity and safety of an adjuvanted recombinant zoster vaccine (RZV) in renal transplant (RT) recipients ≥18 years of age receiving daily immunosuppressive therapy.

Methods

In this phase 3, randomized (1:1), observer-blind, multicenter trial, RT recipients were enrolled and received 2 doses of RZV or placebo 1–2 months (M) apart 4–18M posttransplant. Anti–glycoprotein E (gE) antibody concentrations, gE-specific CD4 T-cell frequencies, and vaccine response rates were assessed at 1M post–dose 1, and 1M and 12M post–dose 2. Solicited and unsolicited adverse events (AEs) were recorded for 7 and 30 days after each dose, respectively. Solicited general symptoms and unsolicited AEs were also collected 7 days before first vaccination. Serious AEs (including biopsy-proven allograft rejections) and potential immune-mediated diseases (pIMDs) were recorded up to 12M post–dose 2.

Results

Two hundred sixty-four participants (RZV: 132; placebo: 132) were enrolled between March 2014 and April 2017. gE-specific humoral and cell-mediated immune responses were higher in RZV than placebo recipients across postvaccination time points and persisted above prevaccination baseline 12M post–dose 2. Local AEs were reported more frequently by RZV than placebo recipients. Overall occurrences of renal function changes, rejections, unsolicited AEs, serious AEs, and pIMDs were similar between groups.

Conclusions

RZV was immunogenic in chronically immunosuppressed RT recipients. Immunogenicity persisted through 12M postvaccination. No safety concerns arose.

Clinical Trials Registration

NCT02058589.

Hepatitis C direct-acting antiviral outcomes in patients 75 years and older

Background and Aim

Elderly patients with hepatitis C virus (HCV) infection have worse interferon‐based treatment outcomes than young patients. Direct‐acting antiviral (DAA) regimens have enabled the treatment of previously difficult‐to‐cure populations. There are few studies that specifically assess DAA treatment outcomes in patients over 75 years of age.

Methods

Design: This was a cohort study. Setting: The setting was three Canadian HCV specialty sites. Participants: Patients aged 75 years and older and treated with DAA without interferon were enrolled. Measurements: Patient demographics, liver fibrosis by transient elastography, treatment regimen, and treatment outcome data were collected.

Results

The mean age of 78 patients in our analysis was 78.6 years (SD 3.5; range: 75–88 years). The most common genotype was 1b (35%). The most frequently utilized regimens included sofosbuvir‐velpatasvir (33%) and ledipasvir‐sofosbuvir (32%). Ribavirin was included for 17% of recipients. Sustained virological response (SVR) was achieved in 94% of patients (69% of those receiving ribavirin and 98% of patients on ribavirin‐free regimens). Ribavirin toxicity contributed to the lower SVR rates in ribavirin‐exposed patients. Ribavirin dosage was decreased in three patients and ultimately discontinued in two of these patients. All treatment was discontinued in another two patients.

Conclusion

Ribavirin‐free DAA therapy is safe and achieves SVR rates in older adults comparable to those described in the general population. RBV inclusion frequently results in complications, often leads to treatment modification or interruption, and does not improve SVR rates in those with advanced age.

Canadian Cardiovascular Society/Canadian Cardiac Transplant Network Position Statement on Heart Transplantation: Patient Eligibility, Selection, and Post-Transplantation Care

Significant practice-changing developments have occurred in the care of heart transplantation candidates and recipients over the past decade. This Canadian Cardiovascular Society/Canadian Cardiac Transplant Network Position Statement provides evidence-based, expert panel recommendations with values and preferences, and practical tips on: (1) patient selection criteria; (2) selected patient populations; and (3) post transplantation surveillance. The recommendations were developed through systematic review of the literature and using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. The evolving areas of importance addressed include transplant recipient age, frailty assessment, pulmonary hypertension evaluation, cannabis use, combined heart and other solid organ transplantation, adult congenital heart disease, cardiac amyloidosis, high sensitization, and post-transplantation management of antibodies to human leukocyte antigen, rejection, cardiac allograft vasculopathy, and long-term noncardiac care. Attention is also given to Canadian-specific management strategies including the prioritization of highly sensitized transplant candidates (status 4S) and heart organ allocation algorithms. The focus topics in this position statement highlight the increased complexity of patients who undergo evaluation for heart transplantation as well as improved patient selection, and advances in post-transplantation management and surveillance that have led to better long-term outcomes for heart transplant recipients.

Global real-world evidence of sofosbuvir/velpatasvir as simple, effective HCV treatment: Analysis of 5552 patients from 12 cohorts

BACKGROUND AND AIMS

Achieving sustained virological response (SVR; cure) in hepatitis C patients using a simple regimen is key to making elimination by 2030 possible. In the largest real-world analysis to date, the effectiveness of pangenotypic, panfibrotic, single-tablet, sofosbuvir/velpatasvir (SOF/VEL) once-daily for 12 weeks was assessed in 12 clinical real-world cohorts from various geographical areas, settings and treatment practices. Factors affecting risk of not achieving SVR were assessed.

METHODS

Adults treated with SOF/VEL 400/100 mg, without ribavirin, were included. All HCV patients reaching Week 12 or 24 post-treatment were assessed for SVR12/24. Factors associated with not achieving SVR12/24 for virological reasons were evaluated using logistic regression analysis.

RESULTS

Overall, 5552 patients were included: 13.3% treatment-experienced; 20.7% compensated cirrhotic; 30.2% genotype 1; 29.5% genotype 2; 32.9% genotype 3; 4.7% genotype 4; 3.7% HIV coinfection; 13.4% current/former intravenous drug use. Of the 5196 patients evaluated for effectiveness, 98.9% achieved SVR12/24. High SVR12/24 rates occurred in all genotypes including genotype 3 (98.3%; 1649/1677) and in those with compensated cirrhosis (97.9; 1055/1078). Only 55 patients did not achieve SVR12/24 due to a virological reason; the only factor statistically significantly associated with an increased risk of not achieving SVR12/24 was compensated cirrhosis (P = .002). Overall, 6% (332/5552) of patients did not achieve SVR12/24 for non-virological reasons (67% lost to follow-up; 26.5% early treatment discontinuation).

CONCLUSIONS

In this large cohort, representative of clinical practice, a simple 12-week regimen of SOF/VEL without ribavirin resulted in high SVR12/24 rates in diverse patient populations, even among those with compensated cirrhosis.

Baseline assessment of and linkage to care for newly diagnosed patients with chronic hepatitis B

BACKGROUND: Patients with chronic hepatitis B (CHB) are at risk of complications and require lifelong monitoring. We evaluated the care of newly diagnosed CHB patients. METHODS: Adult CHB cases newly diagnosed in Alberta between January 1, 2008, and December 31, 2012, were identified, with follow-up through June 1, 2014. Rates of completion of baseline investigations, receipt of antiviral therapy when indicated, and adherence to hepatocellular carcinoma (HCC) screening recommendations in a cohort of high-risk patients were compared between those who did or did not see a CHB specialist. RESULTS: Of 3,333 patients with CHB, 87.1% ( n = 2,904) received non-specialty care. Specialty assessment was associated with higher completion of alanine aminotransferase, hepatitis B e antigen (HBeAg), anti-HBe, and hepatitis B DNA ( p <0.0001) and all four parameters (86.5%) compared with non-specialist care (42.7%; p <0.0001). In a subgroup of high-risk patients for HCC, specialty care was associated with higher completed baseline abdominal ultrasounds ( n = 44; 89.8%,) compared with non-specialist care (62.5%; n = 320; p = 0.0001) and greater adherence to annual surveillance (30.6% versus 15.2%; p = 0.0057). Patients in the HBeAg-positive chronic hepatitis phase meeting criteria for antiviral therapy were more likely to receive treatment under specialty care ( n = 6; 75.0%) than non-specialty care ( n = 27; 33.3%; p = 0.0478). CONCLUSIONS: Our study highlights inadequate care among newly diagnosed CHB patients in Alberta. Specialty assessment was associated with improved quality of care. Interventions are needed to improve linkage to specialty care.

The Z-Profile Study: a multicenter, retrospective cohort study to assess the real-world use and effectiveness of elbasvir/grazoprevir in Canadian adult patients with chronic hepatitis C

Background: Canada was the first country to approve elbasvir/grazoprevir (EBR/GZR) for the treatment of chronic HCV infection for genotypes 1 and 4 with or without ribavirin and genotype 3 with sofosbuvir, with no recommendation for baseline resistance testing. The aim of this study was to describe the effectiveness of EBR/GZR and the profile of patients selected for treatment in a Canadian real-world setting. Methods: This multicenter retrospective study of HCV-infected patients treated with EBR/GZR took place among selected Canadian health care providers, with no exclusion criteria. Primary outcome measures included parameters associated with patient profile and sustained virologic response at 12 weeks (SVR12) and 24 weeks after treatment. Results: A total of 408 patients were included; 244 had available SVR12 information (per-protocol population [PP]). Genotype distribution included 1a (54.7%), 1b (17.2%), 3 (11.8%), 4 (10.0%), and other (6.4%). The majority (88.7%) of participants were treated for 12 weeks without ribavirin. Fifty-nine (14.5%) participants, predominantly with genotype 1a (49/59) infection, were tested for baseline resistance-associated substitutions (bRAS). SVR12 was achieved by 95.9% of the PP. In an exploratory analysis assessing potential predictors of SVR12, participants who had undergone bRAS testing (OR 0.14, 95% CI 0.03–0.64) and participants who had undergone liver transplant (OR 0.05, 95% CI 0.00–0.68) had significantly lower odds of achieving SVR12. Conclusions: This study supports the real-world effectiveness of EBR/GZR—including a broad range of genotypes and diverse fibrosis stages—in the absence of bRAS testing and in special populations.

Non-tuberculous mycobacteria in lung transplant recipients: Prevalence, risk factors, and impact on survival and chronic lung allograft dysfunction

BACKGROUND

Non-tuberculous mycobacteria (NTM) are environmental organisms that colonize or infect lung transplant recipients. Because of differences in populations studied and geographical diversity of species, risk factors for infection and its impact on patient outcomes post transplant are conflicting in the literature.

METHODS

We reviewed the charts of 375 lung transplant recipients at the University of Alberta Hospital (Edmonton, Canada) between 2005 and 2014 to assess NTM epidemiology and risk factors. NTM positivity was determined from a laboratory database. The impact of NTM on patient and graft survival was tested by multivariate Cox regression analysis.

RESULTS

Non-tuberculous mycobacteria were cultured from 26 patients before and 17 patients after transplant. The most commonly isolated species were Mycobacterium avium complex (55%) and Mycobacterium abscessus (20%). Five-year mortality was significantly higher in those infected with NTM after transplant (P = .016), but there was no difference in chronic lung allograft dysfunction (CLAD) at 5 years (P = .999). Cystic fibrosis and lower body mass index were associated with pre-transplant but not post-transplant NTM.

CONCLUSIONS

Isolation of NTM occurred in 7% of patients before and 4.5% of patients after transplant. In this cohort, NTM isolation was associated with increased risk of death but not CLAD onset at 5 years.

Hepatitis C virus-infected kidney waitlist patients: Treat now or treat later?

Currently many but not all centers transplant hepatitis C virus (HCV) viremic positive (+) donor kidneys into HCV+ recipients. Directed donation of HCV+ organs reduces the wait time to transplantation for HCV+ patients. Direct-acting antiviral (DAA) therapy can cure HCV in virtually all who are infected. Some have suggested that treatment of HCV+ waitlisted patients be deferred with the hope that earlier transplantation will provide better outcomes than early DAA therapy. However, there are not enough organs to guarantee prompt transplantation for the current waitlist of infected candidates. A Markov medical decision analysis model was created to compare the overall outcomes of delayed DAA therapy (Option 1) to immediate DAA therapy (Option 2) in waitlisted HCV+ patients. Option 1 patients were modeled to be transplanted 1 year earlier, with a higher cumulative transplant incidence (54% at 5 years post-listing vs 45% for Option 2). Despite this, Option 2 provided 0.43 (95% confidence interval [CI] 0.38-0.49) more life years than Option 1. However, Option 1 was preferred for regions with much greater access to HCV+ organs or in patients with very low HCV+-associated mortality. The best option from an individual patient's perspective will differ by region and candidate.

Hepatitis C: Current Controversies and Future Potential in Solid Organ Transplantation

PURPOSE OF REVIEW

To highlight the changing landscape of hepatitis C virus (HCV) infection in the context of organ transplantation. This focuses on areas of controversy and future potential in the era of highly effective direct-acting antiviral (DAA) agents.

RECENT FINDINGS

Since the advent of safe and highly effective DAA therapy, HCV infection is now curable in virtually all cases, including organ transplant recipients. Excellent drug tolerability and safety combined with high cure rates across all organ groups means that HCV is no longer a barrier to transplantation or its outcomes. Mounting data demonstrate the safety of using organs from HCV-infected donors with subsequent treatment of HCV in the recipient and a potential to expand the donor pool. Historical data demonstrating inferior survival in transplant recipients with HCV is of limited relevance in the DAA era. Virtually all transplant recipients with HCV infection can be cured, while early data also suggest excellent outcomes in recipients of organs from HCV viremic donors. The optimal timing of HCV therapy in relation to transplantation and the optimal use of organs from HCV viremic donors remain areas of controversy and ongoing research efforts.

Canadian Association of General Surgeons position statement: recommendations for surgeons with blood-borne communicable diseases

SUMMARY

The potential for transmission of hematogenously transmitted pathogens during exposure-prone procedures is a clinically important concern to both patients and surgeons. There is inconsistency among regulatory bodies in Canada regarding the management of infection risk among surgeons, particularly with regard to screening and the postexposure management of infected surgeons. The Canadian Association of General Surgeons commissioned a task force to review the evidence regarding the management of blood-borne pathogens and transmission risk during surgical procedures. The results of this review indicate a need for several jurisdictions to update their guidelines to reflect current evidence-based practices.

Epidemiology and risk factors for nosocomial bloodstream infections in solid organ transplants over a 10-year period

BACKGROUND

Bloodstream infections (BSIs) are a leading cause of morbidity and mortality in solid organ transplantation (SOT). We sought to determine the types of nosocomial BSIs and risk factors for them in SOT.

METHODS

Prospectively collected databases of all SOT and nosocomial BSIs occurring at our institution for a 10-year period were reviewed.

RESULTS

From 2003-2012, we observed 157 nosocomial BSI episodes in 2257 SOTs, the majority of which were caused by staphylococci and enterococci (67.5%). The most common sources of BSI were central line, organ space, respiratory, and gastrointestinal. Kidney transplant patients had the lowest risk of acquiring a BSI compared with other SOT types. Lung transplant patients were at increased risk of methicillin-resistant Staphylococcus aureus BSI and heart transplant patients were at increased risk of a Candida albicans BSI, when compared to other organ transplant types. When coagulase-negative Staphylococcus (CoNS) or C. albicans was isolated, the central line was most often the source. The implementation of central-line bundles during the study period correlated temporally with a decreased rate of CoNS BSI. Over the 10-year period, vancomycin-resistant enterococci became the most common enterococcal BSI. Donor-positive cytomegalovirus status was associated with an increased risk of BSI, when compared to donor-negative patients.

CONCLUSIONS

This study demonstrates the common sources, risk factors, and causative organisms of BSI, which can guide empiric antibiotic choices, and highlights areas where preventative interventions could be targeted to prevent nosocomial BSI in SOT.

Characterization of hepatitis B virus genotypes and quantitative hepatitis B surface antigen titres in North American tertiary referral liver centres

BACKGROUND & AIMS

Hepatitis B virus (HBV) genotype and quantitative hepatitis B surface antigen (qHBsAg) have been related to clinical outcome. In this nationwide cross-sectional study, we aimed to investigate the epidemiology and clinical significance of HBV genotype and qHBsAg in patients with chronic hepatitis B (CHB).

METHODS

Six hundred and thirty patients with CHB were seen in four urban tertiary referral centres in Canada. HBV genotype was determined by line probe assay (INNO-LIPA) and HBV DNA quantified by commercial PCR (Roche TaqMan, sensitivity <55 IU/ml or AMPLICOR, sensitivity <60 IU/ml). Titres of qHBsAg were determined by an in-house assay based on the WHO standard (calibration range 0.24-62.5 IU/ml).

RESULTS

In 630 patients (57% male, 69% Asian, median age 42 years), 21% were hepatitis B e antigen positive and the median alanine aminotransferase was 29 U/L. The HBV genotype distribution was A (16%), B (29%), C (31%), D (16%), E (6%). HBV genotype was strongly associated with ethnicity, but neither genotype nor qHBsAg correlated with the degree of fibrosis. In the treatment-naïve patients, the baseline qHBsAg levels correlated with HBV DNA (r = 0.2517, P < 0.0008). The median qHBsAg levels were lowest in patients with genotype B (P < 0.0001), but no significant correlation was noted with all other HBV genotypes.

CONCLUSIONS

In this large North American HBV epidemiological study, genotypes B and C were the most common; however, all genotypes (A-E) were observed with varied distribution nationwide. Baseline qHBsAg significantly correlated with HBV DNA and with HBV genotype B, but not with liver fibrosis.

The natural history of hepatitis C virus infection acquired during childhood

BACKGROUND

The outcome of patients with hepatitis C virus (HCV) infection acquired during childhood in the absence of antiviral therapy is not clear.

AIMS

The purpose of this study was to review the outcome of untreated HCV acquired in childhood. Only population-based studies were included, as referred cases would be predicted to have more severe disease.

METHODS

A systematic review of the literature was completed up to October 2010 to identify studies where a population was screened for HCV infection that was presumably acquired during childhood. Demographical and clinical data were collected on infected patients who had not been treated with an antiviral. Primary outcome was development of a severe adverse outcome (cirrhosis, hepatoma, need for a liver transplant or liver-related death).

RESULTS

There were 25 studies reporting a total of 733 infected patients. Liver biopsy results were provided for 180 patients (25%), revealing cirrhosis in eight (1.0% of the total and 4.0% of those who had a biopsy). None of the other patients developed a severe adverse outcome. As a result of the small number of patients with a severe adverse outcome, risk factors for HCV progression could not be identified.

CONCLUSION

Although HCV can lead to liver transplantation and death during childhood, the vast majority of patients with disease acquired during childhood have slowly progressive disease. There is no clear indication for antiviral therapy in the majority of children with HCV infection.

Granulocyte colony-stimulating factor for hepatitis C therapy-associated neutropenia: systematic review and economic evaluation

Hepatitis C virus (HCV) treatment requires maximal adherence to pegylated interferon (Peg-IFN) and ribavirin to achieve a sustained virologic response (SVR). Neutropenia is the most common cause for Peg-IFN dose reduction. Our objectives were to evaluate the effectiveness, safety and cost-effectiveness of granulocyte colony-stimulating factor (G-CSF) versus Peg-IFN dose reduction for HCV therapy-associated neutropenia in treatment naïve adults. We conducted a systematic review to identify controlled trials and observational studies. Study selection, quality assessment and data extraction were completed independently by two investigators. Cost-effectiveness and cost-utility analyses compared G-CSF with dose reduction. Nineteen studies were included. In one trial, the SVR for those receiving G-CSF was 54.5% (95% CI: 34.7-73.1) compared with 26.3% (95% CI: 11.8-48.8) for dose reduction. The remaining studies were case series or retrospective cohorts and provided weak evidence for the relationship between SVR and G-CSF. The risk of adverse events, including infection, associated with G-CSF was low (13.1%; 95% CI: 8.0-20.8) and clinically insignificant. G-CSF had an incremental cost-effectiveness ratio of $41,701 per SVR achieved in genotype 1, and $16,115 per SVR achieved in genotype 2 or 3. Estimates were robust under a variety of resource and intervention scenarios. While administration of G-CSF may enable patients to remain on or resume optimal HCV therapy, there was weak evidence that this improves the likelihood of SVR compared with dose reduction. Adverse effects of G-CSF are mild. The economic evaluation was inconclusive.

Treatment of hepatitis C in children: a systematic review

BACKGROUND

Current guidelines recommend children be treated for hepatitis C virus (HCV) using the same principles applied in adults. There are however few published studies which assess the efficacy and safety of HCV therapy in children.

METHODOLOGY/PRINCIPAL FINDINGS

A systematic review of the literature was completed for studies of any design that evaluated HCV therapy in children. The primary outcome was sustained virologic response (SVR), with sub-group analysis of response rates by genotype. There were 4 randomized controlled trials (RCTs) and 31 non-randomized studies, all involving interferon, pegylated interferon (PEG-IFN), or combinations of these drugs with ribavirin. The SVR rate could not be directly compared as the populations and interventions differed across studies. Genotype was not reported or differed substantially from study to study. The overall SVR rate for PEG-IFN and ribavirin ranged from 30 to 100% which is comparable to the rate in adults. Similar to adults, the SVR rates were significantly higher in children with genotype 2 or 3 compared to genotype 1. Adverse effects were primarily flu-like symptoms and neutropenia. There were insufficient data to assess the applicability of the week 12 stop rule (stopping therapy at week 12 if there is less than a 2 log drop in HCV RNA) or the efficacy of shortening therapy to 24 weeks in children with genotype 2 and 3.

CONCLUSIONS/SIGNIFICANCE

Current guidelines for the treatment of HCV in children are based on limited data. Further research is needed to define the optimal therapy for HCV in children.

An assessment of donor-to-recipient transmission patterns of human cytomegalovirus by analysis of viral genomic variants

BACKGROUND

We studied human cytomegalovirus (CMV) donor-to-recipient transmission patterns in organ transplantation by analyzing genomic variants on the basis of CMV glycoprotein B (gB) genotyping.

METHODS

Organ transplant recipients were included in the study if they had CMV viremia, if they had received an organ from a CMV-seropositive donor, and if there was at least 1 other recipient of an organ from the same donor who developed CMV viremia. Genotypes (gB1-4) were determined by real-time polymerase chain reaction.

RESULTS

Forty-seven recipients of organs from 21 donors developed CMV viremia. Twenty-three recipients had a pretransplant donor/recipient (D/R) CMV serostatus of D(+)/R(+), and 24 had a serostatus of D(+)/R(-). The prevalences of genotypes in recipients were as follows: for gB1, 51% (n = 24); for gB2, 19% (n = 9); for gB3, 9% (n = 4); for gB4, 0% (n = 0); and for mixed infection, 21% (n = 10). Recipients of an organ from a common donor had infection with CMV of the same gB genotype in 12 (57%) of 21 instances. Concordance between genotypes was higher among seronegative (i.e., D(+)/R(-)) recipients than among seropositive (D(+)/R(+)) recipients, although discordances resulting from the transmission of multiple strains were seen. In seropositive recipients, transmission of multiple strains from the donor could not be differentiated from reactivation of a recipient's own strains.

CONCLUSION

Our analysis of strain concordance among recipients of organs from common donors showed that transmission of CMV has complex dynamic patterns. In seropositive recipients, transmission or reactivation of multiple CMV strains is possible.

Comparison of quantiferon-TB gold with tuberculin skin test for detecting latent tuberculosis infection prior to liver transplantation

Screening for latent tuberculosis infection (LTBI) is recommended prior to organ transplantation. The Quantiferon-TB Gold assay (QFT-G) may be more accurate than the tuberculin skin test (TST) in the detection of LTBI. We prospectively compared the results of QFT-G to TST in patients with chronic liver disease awaiting transplantation. Patients were screened for LTBI with both the QFT-G test and a TST. Concordance between test results and predictors of a discordant result were determined. Of the 153 evaluable patients, 37 (24.2%) had a positive TST and 34 (22.2%) had a positive QFT-G. Overall agreement between tests was 85.1% (kappa= 0.60, p < 0.0001). Discordant test results were seen in 12 TST positive/QFT-G negative patients and in 9 TST negative/QFT-G positive patients. Prior BCG vaccination was not associated with discordant test results. Twelve patients (7.8%), all with a negative TST, had an indeterminate result of the QFT-G and this was more likely in patients with a low lymphocyte count (p = 0.01) and a high MELD score (p = 0.001). In patients awaiting liver transplantation, both the TST and QFT-G were comparable for the diagnosis of LTBI with reasonable concordance between tests. Indeterminate QFT-G result was more likely in those with more advanced liver disease.

Monitoring of polyomavirus BK virus viruria and viremia in renal allograft recipients by use of a quantitative real-time PCR assay: one-year prospective study

We have developed a real-time quantitative PCR (rt-QPCR) assay to detect and kinetically monitor BK virus viruria and viremia in renal transplant recipients (RTRs). A total of 607 urine and 223 plasma samples were collected from 203 individuals including those with BK virus-associated nephropathy (BKVAN) (n = 8), those undergoing routine posttransplant surveillance (SV) (n = 155), those with nontransplant chronic kidney disease (NT-CKD) (n = 20), and healthy living kidney donors (LD) (n = 20). The rt-QPCR assay was found to be highly sensitive and specific, with a wide dynamic range (2.4 to 11 log(10) copies/ml) and very good precision (coefficient of variation, approximately 5.9%). There was a significant difference in the prevalences of viruria and viremia between the BKVAN (100% and 100%) and SV (23% and 3.9%) groups (P < 0.001). No viruria or viremia was detected in LD or in NT-CKD patients. The median (range) peak levels of BK virus viruria and viremia, in log(10) copies/ml, were 10.26 (9.04 to 10.83) and 4.83 (3.65 to 5.86) for the BKVAN group versus 0 (0 to 10.83) and 0 (0 to 5.65) for the SV group, respectively (P < 0.001). When the BK virus load in the urine was <7.0 log(10) copies/ml, no BK virus viremia was detected. When the BK virus load in the urine reached 7.0, 8.0, 9.0, and > or =10.0 log(10) copies/ml, the corresponding detection of BK virus viremia increased to 20, 33, 50, and 100%, respectively. We propose monitoring of BK virus viruria in RTRs, with plasma BK virus load testing reserved for those with viruria levels of > or =7.0 log(10) copies/ml.