Reflex testing automatization for HBsAg carriers: A novel era for hepatitis delta management

With great interest, we read the paper by Adriana Palom et al.[1]Palom A. Rando-Segura A. Vico J. Pacín B. Vargas E. Barreira-Díaz A. et al.Implementation of anti-HDV reflex testing among HBsAg-positive individuals increases testing for hepatitis D.JHEP Rep Innov Hepatol. 2022 Oct; 4: 100547Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar published in JHEP report in 2022 regarding anti-hepatitis delta virus (HDV) reflex testing for HBsAg-positive individuals. The authors demonstrated that less than 10% of HBsAg-positive individuals were tested for HDV in their hospital and even less in primary care centers despite the 2017 recommendations of the European Association for the Study of the Liver.[2]European Association for the Study of the LiverElectronic address: [email protected], European Association for the Study of the Liver. EASL 2017 Clinical Practice Guidelines on the management of hepatitis B virus infection.J Hepatol. 2017 Aug; 67: 370-398Abstract Full Text Full Text PDF PubMed Scopus (3195) Google Scholar In their experience, reflex testing significantly increased the diagnosis of patients with chronic hepatitis delta, including in situations without any identified risk factors. The authors explained that anti-HDV serology was manually added to all HBsAg-positive serum samples. The manual addition of this test can be systematic when performed retrospectively in batches on results showing HBsAg positivity. Otherwise, the process might be more random if the test is added manually in real time after each discovery of HBsAg positivity. However, this latter option is preferable for the rapid management of patients with chronic HDV infection. We automated this reflex testing in our laboratory information management system (LIMS) (TD Nexlab, Technidata, Montbonnot-Saint-Martin, France: Supplementary CTAT Table). Our LIMS allows the implementation of rules when they relate to the last value returned for a given parameter, or in this case, HBsAg positivity. We therefore implemented the following rule: “Any HBsAg positive patients with a negative history or no previous history should trigger the addition of HDV serology.” HBsAg was tested using the HBsAg II assay on Atellica® IM Analyzer (Siemens Healthcare, Courbevoie, France). Anti-HDV antibodies were tested using Murex HDV chemiluminescent immunoassay on a Liaison XL (Diasorin, Antony, France). In the event of positive HDV serology, the serum was sent for HDV RNA detection and quantification to the Hospices Civils de Lyon where RT-PCR was performed as described in Scholtes et al..[3]Scholtes C. Icard V. Amiri M. Chevallier-Queyron P. Trabaud M.A. Ramière C. et al.Standardized one-step real-time reverse transcription-PCR assay for universal detection and quantification of hepatitis delta virus from clinical samples in the presence of a heterologous internal-control RNA.J Clin Microbiol. 2012 Jun; 50: 2126-2128Crossref PubMed Scopus (25) Google Scholar We conducted a retrospective study of HBsAg-positive patients identified in 2021. We identified 201 patients with positive HBsAg during this period (Figure 1A). Among them, 17% had been previously screened for anti-HDV antibodies. For 8%, HDV serology was added by the medical biologist on the same sample when the HBsAg result was released, whereas for 10%, it was added by the clinician at time of the HBsAg result or at the patient’s next visit. Overall, 65% of HBsAg-positive patients were not screened for HDV. Of the 70 patients who underwent HDV serology, seven (10%) were positive, and all benefited from RT-PCR. Six out of the seven patients with positive HDV serology also had positive RT-PCR and received the appropriate medical follow-up. Our automated rule was implemented in October 2022. As the rule only takes into account new HBsAg positivity, we manually added the delta serologies of patients with a previous history of HBsAg positivity but who were never screened for HDV serology. In the 3-month follow-up after the implementation of the rule, 54 HBsAg-positive patients were identified (Figure 1B), including 15 who had previously been screened for HDV. For 19 patients with a history of HBsAg positivity but without HDV screening, HDV serology was manually added. The algorithm automatically screened 20 patients for HDV serology. The addition of retrospective HDV serological analysis for patients with known positive HBsAg as well as the rule for new HBsAg-positive discoveries allowed us to reach 100% HDV screening. The addition of HDV serology in 19 previously known HBsAg-positive patients did not result in the detection of any new HDV seropositivity, which suggested that these patients monitored for hepatitis B must have had HDV screening performed outside our hospital in the past. Of the 20 patients for whom screening was automatically added by the algorithm, four were positive and were thus tested for delta RNA. All four were positive on RT-PCR delta and are currently being treated. Our small study confirms the value of performing HDV reflex testing, which can be performed automatically at the time of the initial positive HBsAg result. This requires the previous batch screening of patients known to be HBsAg positive who have never had HDV screening. However, once this retrospective work is completed, the risk of missed screening becomes almost zero. The generalization and current development of the LIMS increase the potential of automatic interventions to facilitate the work of medical biologists for simple and automatable tasks,[4]Jin D. Wang Q. Peng D. Wang J. Li B. Cheng Y. et al.Development and implementation of an LIS-based validation system for autoverification toward zero defects in the automated reporting of laboratory test results.BMC Med Inform Decis Mak. 2021 Jun 2; 21: 174Crossref PubMed Scopus (3) Google Scholar,[5]Roland K. Yakimec J. Markin T. Chan G. Hudoba M. Customized middleware experience in a tertiary care hospital hematology laboratory.J Pathol Inform. 2022; 13: 100143Crossref PubMed Scopus (0) Google Scholar thus allowing them to focus on more complex cases. In this manner, the automated addition of HDV serology using the LIMS avoids the omissions inherent in human interventions and allows biologists to concentrate on the follow-up of positive patients with the interpretation of complementary testing such as HDV RT-PCR and the communication of results to a specialized clinician, thus improving the management of patients with chronic hepatitis delta. There are no conflicts of interest associated with this publication. MN Hilleret conceived the original idea. E Flacher collected and analysed the data. S Larrat supervised the project and wrote the manuscript with support from J Lupo and R Germi. none. The authors thank Toufik Ariba from the laboratory's IT department for programming the rule in the laboratory information management system. Implementation of anti-HDV reflex testing among HBsAg-positive individuals increases testing for hepatitis DJHEP ReportsVol. 4Issue 10PreviewAlthough EASL guidelines recommend anti-HDV testing in all HBsAg-positive individuals, HDV infection remains an underdiagnosed condition. We describe the impact of an HDV screening program by reflex anti-HDV testing in all HBsAg-positive samples and compare the results before and after its implementation. Full-Text PDF Open Access