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OBJECTIVE: Endoscopic mucosal resection (EMR) is the preferred treatment for non-invasive large (≥20 mm) non-pedunculated colorectal polyps (LNPCPs) but is associated with an early recurrence rate of up to 30%. We evaluated whether standardised EMR training could reduce recurrence rates in Dutch community hospitals. DESIGN: In this multicentre cluster randomised trial, 59 endoscopists from 30 hospitals were randomly assigned to the intervention group (e-learning and 2-day training including hands-on session) or control group. From April 2019 to August 2021, all consecutive EMR-treated LNPCPs were included. Primary endpoint was recurrence rate after 6 months. RESULTS: A total of 1412 LNPCPs were included; 699 in the intervention group and 713 in the control group (median size 30 mm vs 30 mm, 45% vs 52% size, morphology, site and access (SMSA) score IV, 64% vs 64% proximal location). Recurrence rates were lower in the intervention group compared with controls (13% vs 25%, OR 0.43; 95% CI 0.23 to 0.78; p=0.005) with similar complication rates (8% vs 9%, OR 0.93; 95% CI 0.64 to 1.36; p=0.720). Recurrences were more often unifocal in the intervention group (92% vs 76%; p=0.006). In sensitivity analysis, the benefit of the intervention on recurrence rate was only observed in the 20-40 mm LNPCPs (5% vs 20% in 20-29 mm, p=0.001; 10% vs 21% in 30-39 mm, p=0.013) but less evident in ≥40 mm LNPCPs (24% vs 31%; p=0.151). In a post hoc analysis, the training effect was maintained in the study group, while in the control group the recurrence rate remained high. CONCLUSION: A compact standardised EMR training for LNPCPs significantly reduced recurrences in community hospitals. This strongly argues for a national dedicated training programme for endoscopists performing EMR of ≥20 mm LNPCPs. Interestingly, in sensitivity analysis, this benefit was limited for LNPCPs ≥40 mm. TRIAL REGISTRATION NUMBER: NTR7477.
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Pólipos del Colon , Neoplasias Colorrectales , Resección Endoscópica de la Mucosa , Humanos , Pólipos del Colon/cirugía , Colonoscopía , Neoplasias Colorrectales/cirugíaRESUMEN
BACKGROUND: Recognition of submucosal invasive colorectal cancer (T1 CRC) is difficult, with sensitivities of 35â%-60â% in Western countries. We evaluated the real-life effects of training in the OPTICAL model, a recently developed structured and validated prediction model, in Dutch community hospitals. METHODS: In this prospective multicenter study (OPTICAL II), 383 endoscopists from 40 hospitals were invited to follow an e-learning program on the OPTICAL model, to increase sensitivity in detecting T1 CRC in nonpedunculated polyps. Real-life recognition of T1 CRC was then evaluated in 25 hospitals. Endoscopic and pathologic reports of T1 CRCs detected during the next year were collected retrospectively, with endoscopists unaware of this evaluation. Sensitivity for T1 CRC recognition, R0 resection rate, and treatment modality were compared for trained vs. untrained endoscopists. RESULTS: 1 year after e-learning, 528 nonpedunculated T1 CRCs were recorded for endoscopies performed by 251 endoscopists (118 [47â%] trained). Median T1 CRC size was 20âmm. Lesions were mainly located in the distal colorectum (66â%). Trained endoscopists recognized T1 CRCs more frequently than untrained endoscopists (sensitivity 74â% vs. 62â%; mixed model analysis odds ratio [OR] 2.90, 95â%CI 1.54-5.45). R0 resection rate was higher for T1 CRCs detected by trained endoscopists (69â% vs. 56â%; OR 1.73, 95â%CI 1.03-2.91). CONCLUSION: Training in optical recognition of T1 CRCs in community hospitals was associated with increased recognition of T1 CRCs, leading to higher en bloc and R0 resection rates. This may be an important step toward more organ-preserving strategies.
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BACKGROUND & AIMS: Patients with chronic or resolved hepatitis B are at risk of hepatitis B reactivation (HBVr) when treated with high-risk immunosuppressive therapy such as rituximab. Therefore, international guidelines recommend HBV screening prior to rituximab treatment and subsequent antiviral prophylaxis among patients with a (resolved) infection. In this study, we evaluated the adherence to those recommendations. METHODS: This is a retrospective multicentre study including patients treated with rituximab between 2000-2021. Performance of correct screening was assessed, defined as the measurement of hepatitis B surface antigen (HBsAg) and hepatitis B core antibodies (anti-HBc). Next, initiation of antiviral prophylaxis and HBVr rate among patients with a chronic or resolved HBV infection was studied. RESULTS: We enrolled 3,176 patients of whom 1,448 (46%) were screened correctly. Screening rates differed significantly between academic and non-academic hospitals; respectively 65% vs 32% (p<0.001). In addition, screening rates differed across specialties and improved throughout the years; from 32% before 2012 to 75% after 2020 among academic prescribers, versus 1% to 60% among non-academic prescribers (both p<0.001). Antiviral prophylaxis was initiated in 58% vs 36% of the patients with a chronic or resolved HBV infection. Seven patients experienced HBVr, including one fatal liver decompensation. CONCLUSIONS: Many patients treated with rituximab were not correctly screened for HBV infection and antiviral prophylaxis was often not initiated. Although screening rates improved over time, rates remain suboptimal. With the increasing number of indications for rituximab and other immunosuppressive agents these findings could raise awareness among all medical specialties prescribing these agents.
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Virus de la Hepatitis B , Hepatitis B , Humanos , Rituximab/uso terapéutico , Rituximab/efectos adversos , Incidencia , Antivirales/farmacología , Hepatitis B/diagnóstico , Hepatitis B/tratamiento farmacológico , Hepatitis B/epidemiología , Antígenos de Superficie de la Hepatitis B/farmacología , Antígenos de Superficie de la Hepatitis B/uso terapéutico , Anticuerpos contra la Hepatitis B/farmacología , Anticuerpos contra la Hepatitis B/uso terapéutico , Activación ViralRESUMEN
UNLABELLED: Neutropenia during treatment with peginterferon alfa and ribavirin for chronic hepatitis C virus (HCV) infection is a common cause of dose reductions of peginterferon alfa. These reductions are performed to prevent bacterial and fungal infections, which are common during HCV treatment and can be attributed to neutropenia. The aims of this study were to investigate the occurrence of infections and their relation to neutropenia and to identify potential risk factors for infections during HCV treatment. In this single-center cohort study, 2,876 visits of 321 patients treated with peginterferon alfa and ribavirin were evaluated for neutropenia, infections, dose reductions, and potential risk factors for infection during HCV treatment. The baseline mean absolute neutrophil count (ANC) was 3,420 cells/µL, and 16 patients had a baseline ANC of <1,500 cells/µL. During treatment, neutropenia, which was defined as ANC <750 cells/µL, was observed in 95 patients (29.7%) and ANC <375/µL was observed in 16 patients (5%). Ninety-six infections were observed in 70 patients (21.8%). Thirteen infections (13.5%) were defined as severe. Infections were not correlated with neutropenia during treatment. Dose reductions did not lead to a decrease in infection rate. Multivariate logistic regression analysis revealed that age >55 years (odds ratio [OR] 2.06, 95% confidence interval [CI] 1.19-3.56, P = 0.01) and baseline hyperglycemia (OR 2.17, 95% CI 1.15-4.10, P = 0.016) were associated with an increased risk of infection during HCV treatment. Cirrhosis and chronic obstructive pulmonary disease were not risk factors for infection. CONCLUSION: Bacterial infections during treatment with peginterferon alfa and ribavirin are not associated with neutropenia. Older patients and patients with poorly controlled diabetes mellitus have a greater risk of developing infections during HCV treatment.
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Infecciones Bacterianas/etiología , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/efectos adversos , Polietilenglicoles/efectos adversos , Ribavirina/efectos adversos , Adolescente , Adulto , Anciano , Antivirales/efectos adversos , Estudios de Cohortes , Quimioterapia Combinada , Femenino , Hepatitis C Crónica/complicaciones , Humanos , Infecciones , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , Neutropenia/inducido químicamente , Neutropenia/tratamiento farmacológico , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes , Ribavirina/uso terapéutico , Factores de RiesgoRESUMEN
BACKGROUND: Endoscopic mucosal resection (EMR) for large colorectal polyps is in most cases the preferred treatment to prevent progression to colorectal carcinoma. The most common complication after EMR is delayed bleeding, occurring in 7% overall and in approximately 10% of polyps ≥ 2 cm in the proximal colon. Previous research has suggested that prophylactic clipping of the mucosal defect after EMR may reduce the incidence of delayed bleeding in polyps with a high bleeding risk. METHODS: The CLIPPER trial is a multicenter, parallel-group, single blinded, randomized controlled superiority study. A total of 356 patients undergoing EMR for large (≥ 2 cm) non-pedunculated polyps in the proximal colon will be included and randomized to the clip group or the control group. Prophylactic clipping will be performed in the intervention group to close the resection defect after the EMR with a distance of < 1 cm between the clips. Primary outcome is delayed bleeding within 30 days after EMR. Secondary outcomes are recurrent or residual polyps and clip artifacts during surveillance colonoscopy after 6 months, as well as cost-effectiveness of prophylactic clipping and severity of delayed bleeding. DISCUSSION: The CLIPPER trial is a pragmatic study performed in the Netherlands and is powered to determine the real-time efficacy and cost-effectiveness of prophylactic clipping after EMR of proximal colon polyps ≥ 2 cm in the Netherlands. This study will also generate new data on the achievability of complete closure and the effects of clip placement on scar surveillance after EMR, in order to further promote the debate on the role of prophylactic clipping in everyday clinical practice. TRIAL REGISTRATION: ClinicalTrials.gov NCT03309683 . Registered on 13 October 2017. Start recruitment: 05 March 2018. Planned completion of recruitment: 31 August 2021.
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Pólipos del Colon , Resección Endoscópica de la Mucosa , Colon/cirugía , Pólipos del Colon/cirugía , Colonoscopía , Resección Endoscópica de la Mucosa/efectos adversos , Humanos , Estudios Multicéntricos como Asunto , Países Bajos , Hemorragia Posoperatoria/etiología , Hemorragia Posoperatoria/prevención & control , Ensayos Clínicos Controlados Aleatorios como Asunto , Instrumentos QuirúrgicosRESUMEN
BACKGROUND & AIMS: Chronic HCV patients with baseline thrombocytopenia are often excluded from treatment with peginterferon alfa and ribavirin or undergo many dose reductions of peginterferon alfa. The aim of this study was to investigate the correlation between thrombocytopenia and the occurrence of bleedings during antiviral treatment for HCV infection. METHODS: In this single center cohort study 2876 visits of 321 patients treated with peginterferon alfa and ribavirin were evaluated for thrombocytopenia, bleedings and dose reductions during HCV treatment. RESULTS: Mean platelet count at baseline was 207,000/microl for non-cirrhotic patients (n=253) and 132,000/microl for cirrhotic patients (n=68). Mean platelet drop was 42% from 191,000 to 113,100/microl (range 8000-284,000/microl). Severe thrombocytopenia (platelet counts <50,000/microl) was observed in 30 patients (9.3%) at 166 visits and 9 patients developed platelet counts <25,000/microl at 15 visits. Forty-eight bleedings were observed in 27 patients (8.4%). Only one bleeding, due to gastrointestinal angiodysplasia, was defined as severe. However, this patient did not have severe thrombocytopenia at the time of bleeding. During visits, patients reported more minor bleedings when platelet counts were <50,000/microl compared to visits with platelet counts 50,000/microl (11.4% vs. 1.1%, p<0.001). In the multivariate analysis, platelet count of <50,000/microl was a significant predictor of bleeding (p<0.001). CONCLUSIONS: Severe bleedings did not occur in patients with platelet counts below 50,000/microl; based on these findings, treatment with peginterferon alfa and ribavirin appears to be safe in patients with platelet counts below 50,000/microl although platelet counts below 25,000/microl were rare.
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Antivirales/efectos adversos , Hemorragia/etiología , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Interferón-alfa/efectos adversos , Polietilenglicoles/efectos adversos , Trombocitopenia/complicaciones , Adolescente , Adulto , Anciano , Antivirales/administración & dosificación , Estudios de Cohortes , Femenino , Hepatitis C Crónica/sangre , Humanos , Interferón alfa-2 , Interferón-alfa/administración & dosificación , Masculino , Persona de Mediana Edad , Recuento de Plaquetas , Polietilenglicoles/administración & dosificación , Proteínas Recombinantes , Factores de Riesgo , Trombocitopenia/sangre , Adulto JovenRESUMEN
BACKGROUND: Bouveret´s syndrome is defined as a gastric outlet obstruction after passage of a gallstone through a fistula into the duodenum. Due to its rarity, the diagnosis of Bouveret's syndrome is often delayed and causes a high morbidity and mortality rate. CASE SUMMARY: A 93-year-old female presented with worsening pain in the right upper abdomen and vomiting. A gastroscopy revealed fluid retention caused by a massive obstructive stone in the bulbus. Endoscopic laser lithotripsy of the impacted stone was planned after multidisciplinary consultation. A Dornier Medilas H Solvo lithotripsy 350 µm laser fiber (10 Hz, 2 Joules) was used to disintegrate the stone into smaller pieces. The patient recovered completely. CONCLUSION: A mechanical obstruction due to a gallstone that has entered the gastrointestinal tract is a complication that appears in 0.3%-0.5% of patients who have cholelithiasis. Stones larger than 2 cm can become impacted in the digestive tract, which occurs mostly in the terminal ileum. In approximately 1%-3% of cases, the stones cause obstruction in the duodenum. This phenomenon is called Bouveret's syndrome. As this condition is mostly observed in elderly individuals with multiple comorbidities, treatment by an open surgical approach is unsuitable. Endoscopic removal is the preferred technique. The benefit of using laser lithotripsy is the precise targeting of energy onto the stone with minimal tissue injury. Endoscopic laser lithotripsy is a safe and feasible treatment option for Bouveret's syndrome.
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Fístula Biliar/cirugía , Cálculos Biliares/cirugía , Obstrucción de la Salida Gástrica/cirugía , Gastroscopía/métodos , Fístula Intestinal/cirugía , Litotripsia por Láser/métodos , Dolor Abdominal/etiología , Dolor Abdominal/cirugía , Anciano de 80 o más Años , Fístula Biliar/diagnóstico , Fístula Biliar/etiología , Duodeno/diagnóstico por imagen , Femenino , Vesícula Biliar/diagnóstico por imagen , Cálculos Biliares/complicaciones , Cálculos Biliares/diagnóstico , Obstrucción de la Salida Gástrica/diagnóstico , Obstrucción de la Salida Gástrica/etiología , Gastroscopía/instrumentación , Humanos , Fístula Intestinal/diagnóstico , Fístula Intestinal/etiología , Litotripsia por Láser/instrumentación , Estómago/diagnóstico por imagen , Resultado del Tratamiento , Vómitos/etiología , Vómitos/cirugíaRESUMEN
BACKGROUND/OBJECTIVE: Genetic polymorphisms in the inosine triphosphatase (ITPA) gene have been associated with the protection from early ribavirin(RBV)-induced hemolytic anemia among patients with chronic hepatitis C virus (HCV) infection. The aim of the present study was to investigate the association between the functional ITPA variants and hematological side effects during antiviral therapy with pegylated interferon (PegIFN) and RBV. PATIENTS AND METHODS: This cohort study included all consecutive Caucasian patients treated for chronic HCV infection with PegIFN and RBV between 2000 and 2009 for whom a serum sample was available for genetic testing. The predicted inosine triphosphate pyrophosphatase (ITPase) activity was based on the genotypes of the SNPs rs1127354 and rs7270101. Decline in hemoglobin (Hb) during antiviral therapy, as well as dose reductions, blood transfusions and use of erythropoietin were assessed. RESULTS: In total, 213 patients were included. The predicted ITPase activity was normal among 152 (71%) patients; 61 (29%) patients had ITPase deficiency. By multivariable linear regression, RBV dose in mg per kilogram (Beta 0.09, 95%CI 0.04-0.13, p<0.001) and normal ITPase activity (Beta 0.89, 95%CI 0.64-1.14, p<0.001) were associated with more Hb decline at week 4 of treatment. Patients with normal ITPase activity underwent more dose adjustments of RBV than patients with ITPase deficiency (19(13%) vs 1(2%),p = 0.014) and received erythropoietin more frequently (12 (8%) vs 0 (0%),p = 0.024). CONCLUSION: Genetic variants in the ITPA gene protected against RBV treatment-induced anemia among Caucasian patients with chronic HCV infection. Patients with normal ITPase activity underwent more dose reductions of RBV and received erythropoietin more frequently.
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Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/genética , Polimorfismo Genético/genética , Pirofosfatasas/genética , Adulto , Antivirales/efectos adversos , Femenino , Genotipo , Hemoglobinas/metabolismo , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Recuento de PlaquetasRESUMEN
Although in vitro studies have been performed to dissect the mechanism of action of IFNα, detailed in vivo studies on the long-term effects of IFNα on monocytes have not been performed. Here we examined peripheral blood from 14 chronic HCV patients at baseline and 12 weeks after start of IFNα-based therapy. Monocytes were phenotyped by flow-cytometry and their function evaluated upon TLR stimulation and assessed by multiplex cytokine assays. During therapy of HCV patients, monocytes displayed a hyperactive state as evidenced by increased TLR-induced pro-inflammatory cytokine levels, as well as enhanced CD69 and CD83 mRNA and protein expression. Moreover, monocytes from 8 patients at baseline and 12 weeks after start of IFNα-based therapy were transcriptomically profiled by high throughput RNA-sequencing. Detailed RNA-seq analysis of monocytes showed significant ISG mRNA induction during therapy. Importantly, IFNα-based therapy activated TLR7 signaling pathways, as demonstrated by up-regulated expression of TLR7, MyD88, and IRF7 mRNA, whereas other TLR family members as well as CD1c, CLEC4C, and CLEC9A were not induced. The induction of TLR7 responsiveness of monocytes by IFNα in vivo in HCV patients is relevant for the development of TLR7 agonists that are currently under development as a promising immunotherapeutic compounds to treat chronic viral hepatitis.
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Antivirales/administración & dosificación , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/genética , Interferón-alfa/administración & dosificación , Monocitos/inmunología , Receptor Toll-Like 7/inmunología , Transcriptoma/efectos de los fármacos , Adolescente , Adulto , Anciano , Citocinas/genética , Citocinas/inmunología , Femenino , Hepacivirus/efectos de los fármacos , Hepacivirus/fisiología , Hepatitis C Crónica/inmunología , Humanos , Masculino , Persona de Mediana Edad , Monocitos/efectos de los fármacos , Receptor Toll-Like 7/genética , Adulto JovenRESUMEN
Erythropoietin (EPO) is a hormone that controls red blood cell production. Binding of EPO to the EPO-receptor results in increased numbers of red blood cells in the circulation, which makes EPO a potent molecule to treat anemia in various groups of patients. Although numerous studies have examined the clinical effects of EPO, its immunological effects have received less attention. In this study, we examined the immunological effects of EPO on human monocytes. We show that human monocytes express EPO receptor mRNA, and are responsive to EPO in cell culture. In vitro exposure of PBMC from individuals to EPO and the TLR4 ligand LPS showed a significant reduction of monocytes producing IL-6 and TNF, while the frequencies of IL-12p40, IL-10, MIP-1ß and IL-8-producing cells did not change upon incubation with EPO. In addition, EPO did increase the phagocytic activity but did not affect the ability to produce ROS by monocytes. Moreover, we studied eight chronic HCV patients undergoing treatment with peg-IFN and ribavirin, who were administered EPO for treatment-induced anemia. Blood was collected before and 7 days after EPO injection. In 7 patients, we observed a significant decline at day 7 after EPO administration of the frequency of monocytes producing various pro-inflammatory cytokines following stimulation with the TLR4 ligand LPS and the TLR7/8 ligand R848, which is in line with our in vitro findings. Our findings demonstrate an inhibitory effect of EPO on the secretion of effector molecules by monocytes and a stimulatory effect on the phagocytic activity by monocytes.
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Anemia/inducido químicamente , Eritropoyetina/administración & dosificación , Hepatitis C Crónica/tratamiento farmacológico , Monocitos/efectos de los fármacos , Anemia/tratamiento farmacológico , Eritropoyetina/farmacología , Escherichia coli/metabolismo , Hepacivirus/patogenicidad , Hepatitis C Crónica/inmunología , Humanos , Interleucina-6/metabolismo , Ligandos , Lipopolisacáridos/inmunología , Monocitos/inmunología , Monocitos/metabolismo , Fagocitosis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Receptores de Eritropoyetina/genética , Receptores de Eritropoyetina/metabolismo , Ribavirina/efectos adversos , Receptor Toll-Like 4/inmunología , Receptor Toll-Like 4/metabolismoRESUMEN
BACKGROUND: Sustained virological response (SVR) rates in previous non-responders to pegylated interferon (PEG-IFN)-α and ribavirin for chronic HCV remain low (~10%). We hypothesize that continuous subcutaneous delivery of fully potent interferon (IFN)-α2b via an external pump will lead to stable blood concentrations and thereby prevent subtherapeutic trough levels associated with viral breakthrough. The aims of the study were to assess safety, tolerability and virological response in patients who were previous PEG-IFN-α/ribavirin non-responders. METHODS: We randomized 30 HCV genotype 1 (n=24) and genotype 4 (n=6) patients to receive 6, 9 or 12 million units (MU) IFN-α2b daily by continuous subcutaneous administration using an insulin pump (MiniMed(®) 508; Medtronic Inc., Minneapolis, MN, USA) in combination with ribavirin (1,000-1,600 mg) for 48 weeks. RESULTS: The magnitude of viral decline in the 12 MU group after 4 weeks of treatment was 2.67 log HCV RNA compared with 1.21 and 1.27 log HCV RNA in the 9 and 6 MU groups, respectively (P=0.001). In the intention-to-treat analysis, the SVR rate was 20% (6/30). The per-protocol SVR rate was 25% (6/24), of which four out of six patients in the high-dose arm achieved SVR. Adverse events appeared dose-dependent, were mostly mild-to-moderate and were typical of IFN therapy. Five patients developed irritation and/or abscesses at the injection site. Six serious adverse events were reported in five patients. CONCLUSIONS: Continuous delivery of IFN-α2b can induce a strong dose-dependent viral suppression. This could be an effective approach in conjunction with, or as lead-in therapy prior to, treatment with a direct antiviral agent.
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Antivirales/administración & dosificación , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Infusiones Subcutáneas , Interferón-alfa/administración & dosificación , Ribavirina/administración & dosificación , Antivirales/efectos adversos , Antivirales/uso terapéutico , Relación Dosis-Respuesta a Droga , Quimioterapia Combinada , Femenino , Hepacivirus/genética , Hepatitis C Crónica/virología , Humanos , Interferón alfa-2 , Interferón-alfa/efectos adversos , Interferón-alfa/uso terapéutico , Masculino , Persona de Mediana Edad , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/efectos adversos , Proteínas Recombinantes/uso terapéutico , Ribavirina/efectos adversos , Ribavirina/uso terapéutico , Resultado del TratamientoRESUMEN
BACKGROUND: The development of more sensitive HCV RNA assays might necessitate re-evaluation of the rules for stopping treatment (for example, HCV RNA negativity at week 24 during treatment with pegylated interferon-α and ribavirin for chronic hepatitis C). The aim of this study was to assess discordance between the week 24 HCV RNA test results of two PCR-based assays (Amplicor and TaqMan) and the transcription-mediated amplification (TMA) HCV RNA qualitative assay. METHODS: A total of 89 week 24 samples that were negative using PCR-based assays during treatment were retested with the TMA qualitative assay to investigate discordance between tests results. All week 24 samples were HCV RNA negative by Amplicor or by TaqMan. RESULTS: Of the 89 patients, 46 (52%) achieved sustained virological response (SVR). Viral breakthrough or relapse occurred in 43 patients (48%). All 89 HCV RNA negative week 24 samples were retested with the qualitative TMA assay. Eleven out of 89 samples had detectable HCV RNA (12%). All patients with detectable HCV RNA experienced breakthrough or relapse (negative predictive value 100%). Of the 78 patients with undetectable HCV RNA at week 24 using the TMA assay, 46 achieved SVR. This resulted in a positive predictive value (PPV) of 59% for the TMA assay compared with a PPV of 52% for the PCR-based assays. CONCLUSIONS: All patients with detectable HCV RNA at week 24 using the TMA assay eventually relapsed. On the basis of these results, the use of this more sensitive HCV RNA assay could lead to the prevention of unnecessary treatment.