Actualización en el manejo de la infección por Helicobacter pylori. Documento de posicionamiento de la Societat Catalana de Digestologia

Evaluation of a New Monoclonal Chemiluminescent Immunoassay Stool Antigen Test for the Diagnosis of Helicobacter pylori Infection: A Spanish Multicentre Study

The stool antigen test (SAT) represents an attractive alternative for detection of Helicobacter pylori. The aim of this study was to assess the accuracy of a new SAT, the automated LIAISON® Meridian H. pylori SA based on monoclonal antibodies, compared to the defined gold standard 13C-urea breath test (UBT). This prospective multicentre study (nine Spanish centres) enrolled patients ≥18 years of age with clinical indication to perform UBT for the initial diagnosis and for confirmation of bacterial eradication. Two UBT methods were used: mass spectrometry (MS) including citric acid (CA) or infrared spectrophotometry (IRS) without CA. Overall, 307 patients (145 naïve, 162 with confirmation of eradication) were analysed. Using recommended cut-off values (negative SAT < 0.90, positive ≥ 1.10) the sensitivity, specificity, positive predictive value, negative predictive value and accuracy were 67%, 97%, 86%, 92% and 91%, respectively, obtaining an area under the receiver operating characteristic (ROC) curve (AUC) of 0.85. Twenty-eight patients, including seven false positives and 21 false negatives, presented a discordant result between SAT and UBT. Among the 21 false negatives, four of six tested with MS and 11 of 15 tested with IRS presented a borderline UBT delta value. In 25 discordant samples, PCR targeting H. pylori DNA was performed to re-assess positivity and SAT accuracy was re-analysed: sensitivity, specificity, positive predictive value, negative predictive value, accuracy and AUC were 94%, 97%, 86%, 99%, 97% and 0.96, respectively. The new LIAISON® Meridian H. pylori SA SAT showed a good accuracy for diagnosis of H. pylori infection.

Minimum inhibitory concentrations of commonly used antibiotics against Helicobacter Pylori: A multicenter study in South China

Aim

To determine the minimum inhibitory concentrations (MICs) of commonly used antibiotics against Helicobacter Pylori (H. pylori) in South China and compare their resistance rates by using EUCAST breakpoints and other breakpoints.

Methods

Patients who had not previously received H. pylori treatment in clinical centers in South China were enrolled in this study from 2017 to 2020. Gastric biopsies were obtained for H. pylori culture. The MICs of amoxicillin (AMX), clarithromycin (CLA), metronidazole (MTZ), levofloxacin (LEV), tetracycline (TET) and furazolidone (FZD) were tested by broth microdilution method and assessed by two different breakpoints. ATCC43504 standard strain served as a control.

Results

A total of 208 H. pylori strains were isolated from patients’ biopsy samples. The MICs of AMX, CLA, MTZ, LEV, TET and FZD for H. pylori were 0.0156-256mg/L (MIC₅₀ 0.125mg/L, MIC₉₀ 4mg/L), 0.0156- >256 mg/L (MIC₅₀ 0.0312mg/L, MIC₉₀ 64mg/L), 0.0156- >256mg/L (MIC₅₀ 8mg/L, MIC₉₀ 256mg/L), 0.0156-256mg/L (MIC₅₀ 0.25mg/L, MIC₉₀ 16mg/L), 0.0156-256mg/L (MIC₅₀ 0.0625mg/L, MIC₉₀ 4mg/L), and 0.0156- >256mg/L (MIC₅₀ 0.0312mg/L, MIC₉₀ 2mg/L), respectively. The MICs of AMX, CLA, MTZ, LEV, TET and FZD for ATCC43504 strain were 0.25mg/L, 0.0625mg/L, 64mg/L, 0.5mg/L, 1mg/L and 0.25mg/L, respectively. The resistance rate of FZD was 11.05%. The overall resistance rates according to EUCAST breakpoints and other breakpoints were 57.21% and 14.90% for AMX (p<0.001), 38.94% and 38.94% for CLA (p = 1), 39.42% and 50.96% for MTZ (p<0.001), 12.98% and 10.58% for TET (p = 0.025), 35.10% and 35.10% for LEV (p = 1), respectively.

Conclusions

Our results demonstrate that AMX, FZD, and TET, but not MTZ, CLR or LEV, showed good anti-H. pylori activity in vitro in South China. When different breakpoints were used, similar results were found with CLA, and LEV, but not with AMX, MTZ, or TET.

Efficiency of Diagnostic Testing for Helicobacter pylori Infections-A Systematic Review

Background: The most recommended treatment for a Helicobacter pylori infection is high doses of combined antibiotics. The objective of this article is to perform a systematic review of the economic evaluation studies applied to assess the efficiency of diagnostic testing for H. pylori infections, so that their main characteristics can be identified and to learn from the literature how the antimicrobial resistance (AMR) issue is incorporated into these economic evaluations. Methods: We conducted a systematic review to compare the costs and clinical effectiveness of diagnostic strategies for H. pylori infections. We followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines and extracted the items from the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) checklist. Results: We found thirteen articles that were of good quality according to CHEERS: six studies focused on diagnostics of Helicobacter pylori infections associated with dyspepsia and four on duodenal ulcers. Testing was found to be the most cost-effective strategy in eight articles. Four studies considered AMR. Conclusions: Testing was more cost-effective than empirical treatment, except in cases of high prevalence (as with developing countries) or when patients could be stratified according to their comorbidities. The introduction of AMR into the model may change the efficiency of the testing strategy.

Molecular Detection of Antibiotic-Resistant Helicobacter pylori

Antimicrobial susceptibility testing (AST) for H. pylori is essential to accurately assess the prevalence of antibiotic resistance in each population. Antibiotic resistance rates form the basis of local guidelines for H. pylori treatment and AST may also be used as a personalized medicine approach to tailor therapy. This chapter provides an update on global antibiotic resistance rates and describes molecular mechanisms that confer H. pylori antibiotic resistance. An overview on the advantages and limitations of molecular AST using both invasive and noninvasive approaches is also provided.

Helicobacter pylori "Test-and-Treat" strategy with urea breath test: A cost-effective strategy for the management of dyspepsia and the prevention of ulcer and gastric cancer in Spain-Results of the Hp-Breath initiative

BACKGROUND

Data from clinical trials comparing Helicobacter pylori (H. pylori) management strategies in patients with dyspepsia are limited. Cost-effectiveness simulation models might help to identify the optimal strategy.

OBJECTIVE

To assess the cost-effectiveness of the H. pylori "Test and Treat" (T&T) strategy including the use of urea breath test (UBT) vs symptomatic treatment (ST) and vs upper gastrointestinal endoscopy (UGE) as a first procedure in patients with dyspepsia.

METHODS

Three main strategies: "T&T" strategy including the use of UBT, "UGE" and "ST" have been compared using cost-effectiveness models developed in accordance with the Spanish medical practice. For the model simulations, a time horizon of 4 weeks was considered for the endpoint "Dyspepsia symptoms relief" and 10 years when using "Peptic ulcer avoided" and "Gastric cancer avoided" endpoints.

RESULTS

For the endpoint "Dyspepsia symptoms relief", T&T strategy appears to be the most cost-effective (883€/success) compared to UGE strategy and to ST strategy (respectively 1628€ and 990€/success). For the endpoint "Probability of peptic ulcer", the T&T strategy appears to be the most cost-effective (421€/peptic ulcer avoided/y) compared to UGE strategy and ST strategy (respectively 728€ and 632€/peptic ulcer avoided/y). For the endpoint "Gastric cancer avoided", the T&T strategy appears to be the most cost-effective (524€/gastric cancer avoided/y) compared to UGE strategy and "ST" strategy (respectively 716€ and 696€/gastric cancer avoided/y).

CONCLUSIONS

T&T strategy including the use of UBT is the most cost-effective medical approach for management of dyspepsia and for the prevention of ulcer and gastric cancer.

[Helicobacter pylori infection in the HIV + population: a comorbidity to think about]

Introducción

. Las alteraciones gastrointestinales, son frecuentes en VIH+. Helicobacter pylori puede ser una causa infradiagnosticada.

Material y métodos

Se realizó una búsqueda retrospectiva de pacientes VIH+ con infección por H. pylori entre enero de 1998 hasta diciembre de 2017.

Resultados

Se incluyeron 132 pacientes. La dispepsia fue la sintomatología más frecuente. Un 88,5% tuvo gastritis crónica atrófica. Se consiguió la erradicación en 102 (77,3%). La curación fue más frecuente con pauta cuádruple (p=0,004) y en los más jóvenes (p=0,041).

Conclusión

La infección por H. pylori podría ser responsable de manifestaciones digestivas inespecíficas en los pacientes VIH+.

Treatment of Helicobacter pylori infection in 2018

Treatment options for the eradication of Helicobacter pylori continue to evolve. There have been many guidelines for H. pylori treatment published, which may lead to some confusion. However, most are in agreement with the most recent iteration of the Maastricht treatment guidelines. Triple therapy is still the most frequently used treatment, especially in areas of low clarithromycin resistance. Its best results are achieved when taken for a minimum of 10 days and with high-dose acid suppression. Quadruple therapy is gaining in popularity particularly in areas with increasing resistance to standard triple therapy. Whether three antibiotics, or bismuth and two antibiotics are used, excellent eradication rates are achieved, albeit with increased side effects. Levofloxacin second-line therapy is widely used; however bismuth, when available, is an increasingly successful option. Sequential therapy is challenging in terms of compliance and is no longer recommended. This past year witnessed a notable increase in the number of studies based on antimicrobial susceptibility testing and tailored eradication therapy, reflecting the role of culture-guided treatment, which may well represent the future of H. pylori treatment and prevent the inappropriate use of antibiotics.