Diagnostic accuracy of Abbott Architect Assay as a screening tool for human T-cell leukaemia virus type-1 and type-2 infection in a London teaching hospital with a large solid organ transplant centre.

AIM: In the United Kingdom, organ donors/recipients are screened for evidence of human T-cell leukaemia virus type-1 and type-2 (HTLV-1/2) infections. Since the United Kingdom is a low prevalence country for HTLV infections, a screening assay with high sensitivity and specificity is required. Samples with repeat reactivity on antibody testing are sent to a reference lab for confirmatory serological and molecular testing. In the case of donor screen, this leads to delays in the release of organs and can result in wastage. We aim to assess whether a signal/cut-off (S/CO) ratio higher than the manufacturer's recommendation of 1.0 in the Abbott Architect antibody assay is a reliable measure of HTLV-1/2 infection. METHODS: We conducted a 5 year retrospective analysis of 7245 patients from which 11 766 samples were tested on the Abbott Architect rHTLV I/II assay. Reactive samples (S/CO >1) were referred for confirmatory serological and molecular detection (Western Blot and proviral DNA) at UK Health Security Agency, (formerly PHE, Colindale), the national reference laboratory. Electronic, protected laboratory and hospital patient databases were employed to collate data. RESULTS: A total of 45 patients had initially reactive samples. 42.2% (n = 19/45) had an S/CO ratio > 20, with HTLV infection confirmed in n = 18/19 and indeterminate confirmatory results in n = 1/19. No samples with an S/CO ratio <4 (48.9%, n = 22/45) or 4-20 (8.9%, n = 4/45) had positive confirmatory results on subsequent confirmatory testing. CONCLUSION: Samples with an S/CO >20 likely represent a true HTLV-1/2 infection. Reactive samples with an S/CO <4 were unlikely to confirm for HTLV infections. Interpretation of these ratios can assist clinicians in the assessment of low reactive samples and reiterates the need for faster access to confirmatory testing.

Acute hepatitis E mimicking a flare of disease in a patient with chronic autoimmune hepatitis.

 Acute hepatitis E is becoming increasingly recognised in Europe with up to 40% of the population in Southern France being exposed to the virus, which is harboured in pigs. Patients with known liver disease may present with acute hepatitis E and present a diagnostic challenge. For example patients with autoimmune hepatitis (AIH) who are immunosuppressed and contract hepatitis E may be at increased risk of developing chronicity due to concurrent immunosuppression. Importantly, the diagnosis may be missed with the infection misdiagnosed as an autoimmune flare, and immunosuppression increased by the attending physician, thus enhancing the risk of chronicity of infection leading to progressive liver injury in immunocompromised patients. We report a case of acute hepatitis E in a patient with AIH and discuss the features that helped us differentiating it from an autoimmune flare.

Transmission of Hepatitis B Core Antibody and Galactomannan Enzyme Immunoassay Positivity via Immunoglobulin Products: A Comprehensive Analysis.

BACKGROUND: Therapeutic immunoglobulins are used as replacement or immunomodulatory therapy, but can transmit clinically important molecules. We investigated hepatitis B virus (HBV) antibodies and galactomannan enzyme immunoassay (GM-EIA) positivity. Detection of HBV core antibody may prompt antiviral prophylaxis when commencing therapy such as rituximab; a positive GM-EIA result prompts investigation or treatment for invasive fungal disease. METHODS: We performed a cross-sectional analysis of HBV serology in 80 patients established (>6 months) on immunoglobulin therapy; prospective analysis of HBV serology in 16 patients commencing intravenous immunoglobulin (IVIG); and pre- and post-infusion analysis of GM-EIA in 37 patients receiving IVIG. RESULTS: Pre-IVIG, 9 of 80 patients tested positive for HBV surface antibody and 1 of 80 tested equivocal for HBV core antibody. On IVIG, 79 of 79 tested positive for surface antibody, 37 of 80 tested positive for core antibody, and 10 of 80 tested equivocal for core antibody. There were significant differences by product, but among patients receiving products that appear to transmit core antibody, negative results correlated with lower surface antibody titers and longer time since infusion, suggesting a simple concentration effect. There was a progressive increase with each infusion in the percentage of patients testing positive for HBV core antibody among patients newly commencing IVIG. Some patients "seroreverted" to negative during therapy. Certain IVIG products tested positive for GM-EIA and there were rises in index values in corresponding patient samples from pre- to post-infusion. Overall, 5 of 37 patient samples pre-infusion and 15 of 37 samples post-infusion tested positive for GM-EIA. CONCLUSIONS: HBV antibodies and GM-EIA positivity are common in patients receiving IVIG and confound diagnostic results.

Management of hepatitis B in pregnant women and infants: a multicentre audit from four London hospitals.

BACKGROUND: Pregnant women with hepatitis B virus (HBV) infection can transmit the infection to their infants, screening of patients and appropriate interventions reduce vertical transmission. This audit was conducted to assess adherence to the national guidelines for management of HBV infection in pregnancy. METHODS: A retrospective audit was conducted on pregnant women diagnosed with hepatitis B on screening in antenatal clinics, across four hospitals in London over 2 years (2009-2010). Data was collected from antenatal records and discharge summaries using a standard audit form. The outcomes measured included HBV serological markers, HBV DNA, detection of other blood borne viruses and referral to hepatology services, administration of active and passive prophylaxis to infants at birth. Descriptive statistics are presented. Proportions were compared using the χ2 test and 95% confidence intervals (CI) were calculated for prevalence estimates. Analyses were conducted using STATA 12. RESULTS: HBsAg was detected in 1.05% (n = 401, 95% CI 0.95-1.16) of women attending an antenatal appointment, 12% (n = 48) of the women were at a high risk of vertical transmission (HBe Ag positive or antiHBe and HBeAg negative or HBV DNA >106 IU/ml). Only 62% (n = 248) women were referred to hepatology or specialist clinics and 29% (n = 13) of women of high infectivity were on antiviral agents. Testing for hepatitis C and delta virus was suboptimal. 75% (n = 36) of the infants at a high risk of acquisition of HBV received both active and passive prophylaxis. CONCLUSION: In certain sectors of London, implementation of the pathway for management of women with hepatitis B and their infants is suboptimal. National guidelines should be followed and improved intersectorial sharing of information is needed to reduce the risk of women of high infectivity being lost to follow up.

Opt-out testing for hepatitis B and C infections in adults attending the emergency department of a large London teaching hospital.

BACKGROUND: The National Health Service (NHS) in England commissioned opt-out testing in London Emergency Departments (ED) in April 2022 to allow early identification and management of hepatitis B (HBV) and hepatitis C virus (HCV) infection in patients unaware of their infection status. METHODS: All adults over the age of 16 undergoing blood tests in the ED at the Royal Free Hospital were tested for HBV surface antigen and anti-HCV IgG unless they opted out. Data was collected between the 12th of April and 22nd of August 2022. OUTCOME: Of 11,215 patients tested for HCV, 164 patients were found to be anti-HCV IgG positive, giving a seroprevalence rate of 1.46 %. 52 of the anti-HCV IgG positive patients did not have any previous HCV serology result. 23 of the anti-HCV IgG positive patients were also HCV RNA positive giving an RNA seroprevalence of 0.21 %, and 17 of those were new diagnoses of HCV viraemia. For HBV testing, 82 (0.73 %) out of 11,192 patients tested were found to be HBsAg positive, including one patient who presented acutely with a positive HBV core IgM. 39 of the HBsAg positive patients were previously unknown to us; of these, 9 had an HBV viral load of more than 2000 IU/mL, including 3 patients with positive HBV e antigen and one patient with hepatitis D virus co-infection. CONCLUSION: Opt-out screening of HBV and HCV in ED is effective at identifying patients with previously undiagnosed viral hepatitis infection and providing an opportunity to engage them in specialist care.

Hepatitis E infection in stem cell and solid organ transplantpatients: A cross-sectional study: The importance of HEV RNA screening in peri-transplant period.

BACKGROUND: Hepatitis E Virus (HEV) is a common cause of acute viral hepatitis worldwide. Typically associated with a self-limiting illness, infection may persist in immunosuppressed populations with significant morbidity and mortality. Based on clinical data published world-wide, UK blood safety guidance recommends the universal screening for HEV RNA of blood donors and donors of tissue, organs and stem cells. OBJECTIVES: This cross-sectional study aimed to determine the point prevalence of HEV viraemia and clinical course of viraemic patients in the peri-transplant period in solid organ transplant (SOT) and haematopoietic stem cell transplant (HSCT) recipients transplanted over a 3-year period (2013-2015). STUDY DESIGN: Nucleic acid extracts of whole blood from patients undergoing SOT or HSCT were tested by an in-house real-time reverse-transcriptase polymerase chain reaction assay for HEV RNA. Samples were tested at baseline (time of transplant), 30, 60 and 90 days post-transplant. RESULTS: 870 patients (259 HSCT, 262 liver and 349 kidney transplant) were included with 2554 samples meeting the inclusion criteria. No kidney transplant patients had HEV viraemia at time of testing. One HSCT and three liver transplant patients were found to be HEV RNA positive. Overall this represented 0.46% of the patients testing positive for HEV viraemia. CONCLUSIONS: Prevalence of HEV viraemia in SOT and HSCT patients in U.K. although higher than in the general population is low at baseline and remains low throughout the early post-transplant phase. Clearance of viraemia can be maintained despite ongoing immunosuppression. Prospective U.K. studies are necessary to inform screening policies in this population.

Disseminated adenovirus infection after allogeneic stem cell transplant and the potential role of brincidofovir - Case series and 10 year experience of management in an adult transplant cohort.

BACKGROUND: Adenovirus infection is a recognized complication following haematopoietic stem cell transplantation. We present a review of our experience of these infections in our transplant cohort over 10 years including 3 patients treated with the novel antiviral brincidofovir. OBJECTIVES: We aimed to describe the presentation, response to treatment and outcomes of adult stem cell transplant patients with disseminated adenovirus infection. STUDY DESIGN: All adult cases of disseminated adenovirus infection following haematopoietic stem cell transplant in our unit between 2005 and 2015 were identified. Transplant details and data on timing of diagnosis, course of infection, viral co-infection and treatment were collected. RESULTS: Of 733 patients transplanted, 10 patients had disseminated infection, including 4 male and 6 female patients with median age of 36.5 (range 19-59) years. 6/10 received an allograft from an unrelated donor. Median post-transplant time to detection of viraemia was 67days (range 20-1140days). Median peak viral load was 3133 copies/ml (352-11,000,000) in survivors received cidofovir alone, one cidofovir then brincidofovir and two brincidofovir alone. 8/10 p and 1,580,000 copies/ml (41,999-3,000.000) in those who died. Five patientsatients had a decrease in viral load following antivirals and/or reduction in immunosuppression including all on brincidofovir. Three died on treatment. CONCLUSIONS: Disseminated adenovirus infection is uncommon in adult transplant patients and uncertainties remain surrounding effective treatment. In our cohort, brincidofovir has shown promise in treatment of adenoviral infection. However, randomized controlled studies are required to confirm this impression.

Hepatitis delta virus testing, epidemiology and management: a multicentre cross-sectional study of patients in London.

BACKGROUND: Hepatitis delta virus (HDV) testing is recommended for all patients with hepatitis B virus (HBV) infection. HDV infection is associated with severe liver disease and interferon is the only available treatment. OBJECTIVES: To determine the rate of anti-HDV antibody testing in HBV patients; and to describe the epidemiology, clinical characteristics and management of HDV-infected patients at four hospitals in London. STUDY DESIGN: The anti-HDV testing rate was estimated by reviewing clinical and laboratory data. Cross-sectional data collection identified HDV-infected patients who had attended the study centres between 2005 and 2012. RESULTS: At a centre with clinic-led anti-HDV testing, 40% (67/168) of HBV patients were tested. Recently diagnosed HBV patients were more likely to be screened than those under long-term follow-up (62% vs 36%, P=0.01). At a centre with reflex laboratory testing, 99.4% (3543/3563) of first hepatitis B surface antigen positive samples were tested for anti-HDV. Across the four study centres there were 55 HDV-infected patients, of whom 50 (91%) had immigrated to the UK and 27 (49%) had evidence of cirrhosis. 31 patients received interferon therapy for HDV with an end of treatment virological response observed in 10 (32%). CONCLUSIONS: The anti-HDV testing rate was low in a centre with clinic-led testing, but could not be evaluated in all centres. The HDV-infected patients were of diverse ethnicity, with extensive histological evidence of liver disease and poor therapeutic responses. Future recommendations include reflex laboratory testing algorithms and a prospective cohort study to optimise the investigation and management of these patients.

Evaluation of sequencing of HCV core/E1, NS5A and NS5B as a genotype predictive tool in comparison with commercial assays targeting 5'UTR.

BACKGROUND: Hepatitis C virus (HCV) genotyping is required for tailoring the dose and duration of antiviral therapy, predicting virological response rates, and selecting future treatment options. OBJECTIVE: To establish whether baseline genotypes, performed by INNO-LiPA Version 1.0 (v1.0), before 2008, were valid for making treatment decisions now or whether genotypic determination should be repeated. Furthermore, to evaluate concordance between Abbott RealTime genotype II assay (RT) and genotyping by sequencing HCV C/E1, NS5A, NS5B. STUDY DESIGN: Genotyping by RT and sequencing was performed on paired historic and current specimens from 50 patients previously baseline genotyped using INNO-LiPA. RESULTS: Of 100 samples from 50 patients, ≥ 2 of HCV genomic target regions yielded a sequence that was suitable for genotyping, with 100% concordance, providing no evidence of recombination events. Genotype and subtype prediction based on RT and sequencing agreed in 62.8% historic and 72.7% current specimens, with a kappa coefficient score of 0.48 and 0.76, respectively. LiPA could not subtype 46% of HCV gt1 infections, and LiPA subgenotype was only in agreement with RT and sequencing in 28.6% cases, where matched baseline and historic specimens were available. Three patients were indeterminate by RT, and five patients with HCV gt1 infections could not be subtyped by RT. However, RT revealed mixed infections in five patients where sequencing detected only single HCV infection at 20% threshold. CONCLUSION: Genotyping by sequencing, exhibited excellent concordance, with moderate to good agreement with RT, and could resolve RT indeterminates and subtype HCV-gt1 infections not possible by LiPA.

Comparison of automated chemiluminescence immunoassays with capture enzyme immunoassays for the detection of measles and mumps IgM antibodies in serum.

Outbreaks of measles and mumps occur regularly in the UK. Rapid diagnosis of acute infection is important for both infection control and epidemiological purposes. The objective of this study was to compare the performance of an automated platform (DiaSorin Liaison(®), Saluggia, Italy) with a manual capture enzyme immunoassay (EIA; Microimmune, Hounslow, UK) for the detection of measles and mumps IgM antibodies in serum from symptomatic individuals. Ninety sera tested previously for measles (n=50) and mumps (n=40) IgM using the manual EIA were tested retrospectively using the DiaSorin Liaison(®) and the results compared. Sensitivity, specificity, inter-assay variability and intra-assay variability of the Liaison(®) assays were calculated. Sensitivity and specificity of the Liaison(®) assay for measles IgM were 92% and 100% respectively, with inter-assay variation of 14.1% and intra-assay variation of 12.5%. The sensitivity and specificity of the mumps IgM Liaison(®) assay were 88% and 95% respectively, with an inter-assay and intra-assay variation of 13.9% and 5.3% respectively. Both the measles and mumps IgM Liaison(®) assays gave fewer equivocal results than the EIA. Neither Liaison(®) IgM assay showed any cross-reactivity with sera positive against other viruses, however the measles IgM EIA cross-reacted with parvovirus IgM. The automated Liaison(®) assays are more specific, cheaper and less labour-intensive compared to the manual EIA. The Liaison(®) assays benefit from reduced number of equivocal results compared to the EIA for both measles and mumps IgM. This allows clinical decisions to be made accurately and in a timely manner.

Telaprevir or boceprevir based therapy for chronic hepatitis C infection: development of resistance-associated variants in treatment failure.

The use of triple-therapy, pegylated-interferon, ribavirin and either of the first generation hepatitis C virus (HCV) protease inhibitors telaprevir or boceprevir, is the new standard of care for treating genotype 1 chronic HCV. Clinical trials have shown response rates of around 70-80%, but there is limited data from the use of this combination outside this setting. Through an expanded access programme, we treated 59 patients, treatment naïve and experienced, with triple therapy. Baseline factors predicting treatment response or failure during triple therapy phase were identified in 58 patients. Thirty seven (63.8%) of 58 patients had undetectable HCV RNA 12weeks after the end of treatment. Genotype 1a (p=0.053), null-response to previous treatment (p=0.034), the rate of viral load decline after 12weeks of previous interferon-based treatment (p=0.033) were all associated with triple-therapy failure. The most common cause of on-treatment failure for telaprevir-based regimens was the development of resistance-associated variants (RAVs) at amino acids 36 and/or 155 of HCV protease (p=0.027) whereas in boceprevir-based regimens mutations at amino acid 54 were significant (p=0.015). SVR12 rates approaching 64% were achieved using triple therapy outside the clinical trial setting, in a patient cohort that included cirrhotics.

Acute Hepatitis E Mimicking a Flare of Disease in a Patient with Chronic Autoimmune Hepatitis

Abstract: Acute hepatitis E is becoming increasingly recognised in Europe with up to 40% of the population in Southern France being exposed to the virus, which is harboured in pigs. Patients with known liver disease may present with acute hepatitis E and present a diagnostic challenge. For example patients with autoimmune hepatitis (AIH) who are immunosuppressed and contract hepatitis E may be at increased risk of developing chronicity due to concurrent immunosuppression. Importantly, the diagnosis may be missed with the infection misdiagnosed as an autoimmune flare, and immunosuppression increased by the attending physician, thus enhancing the risk of chronicity of infection leading to progressive liver injury in immunocompromised patients. We report a case of acute hepatitis E in a patient with AIH and discuss the features that helped us differentiating it from an autoimmune flare.

Herpetic neonatal pustular rash.

Pustular rash in a neonate is very common and is usually associated with staphylococcal infection. The present report describes the case of a 12-day-old neonate with a pustular rash, secondary to herpes simplex infection. A high index of suspicion is necessary in neonates presenting with suggestive signs, especially with negative bacterial cultures. Prompt initiation of aciclovir treatment after obtaining diagnostic samples may be life-saving.