An optimized 13C-urea breath test for the diagnosis of H pylori infection

Helicobacter pylori infection prevalence in ambulatory settings in 2017-2019 in RUSSIA: The data of real-world national multicenter trial

BACKGROUND

The recent data on the prevalence of Helicobacter pylori (H. pylori) infection in Russia are limited. The aim of the study was to compare Helicobacter pylori infection prevalence in ambulatory settings in Russia in 2017 and 2019 years.

MATERIALS AND METHODS

Subjects visiting primary care centers were invited to take part in the study. H. pylori status was assessed by ¹³ C-urea breath test (UBT). Data on subjects' demography, previous treatment exposure, and place of residence were collected in all federal districts of Russia in 2017 and in 2019 calendar years and processed centrally.

RESULTS

The data of 19,875 subjects were available for analysis. The prevalence of H. pylori infection assessed by positive UBT in treatment-naive subjects was highest in the Southern (54.9%) and the North Caucasian (45.1%) federal districts. A significant difference (p < 0.05) in H. pylori prevalence between two testing periods was found only in a half of federal districts: the Central (46.2% in 2017 vs. 36.2% in 2019), the Northwestern (38.6% vs. 35.5% accordingly), the Volga (40.6% vs. 33.0%, accordingly), and the Ural (40.4% vs. 32.7%, accordingly). The lowest prevalence of H. pylori infection was revealed in the age group <18 years old (20.2%), while the highest in the age group of 41-50 years old (43.9%). In 2017, the prevalence of H. pylori was significantly (p < 0.05) higher than in 2019 in all age groups but younger than 18 and older than 70 y.o., where similar rates were found during both study periods.

CONCLUSIONS

The prevalence of H. pylori according to ¹³ C-UBT testing of primary care visitors in Russia is lower than expected (38.8%). The highest prevalence of H. pylori infection found in the Southern and the North Caucasian federal districts of Russia and in the age group of 41-50 years old. This study was registered at clinicaltrials.gov (NCT04892238).

Determinación de Helicobacter spp. en mucosa gástrica glandular de mulas a través de la prueba de la actividad de la ureasa e histopatología

La información sobre la presentación y los factores predisponentes del síndrome de úlcera gástrica en mulas (SUGM) es escasa en comparación con el síndrome de úlcera gástrica en equinos (SUGE) y asnales. Debido a la naturaleza multifactorial de este síndrome, la helicobacteriosis ha sido estudiada en otras especies. El objetivo fue establecer la presencia de Helicobacter spp. en mucosa gástrica de mulas a través de la prueba rápida de la ureasa (PRU) y de análisis histopatológico. Menos del 27% de las muestras reaccionaron a la PRU, con tiempos prolongados de reacción, y al Agar Urea (prueba de oro), con menor porcentaje de positividad. La histopatología reveló procesos inflamatorios crónicos, sin presencia de bacterias curvoespiraladas. Las PRU no fueron conclusivas en la determinación de Helicobacter spp., comportamiento similar reportado en equinos. Se requieren exámenes diagnósticos específicos y procedimientos complementarios que explore regiones del estómago en consideración del número de muestras representativas.

A re-testing range is recommended for 13C- and 14C-urea breath tests for Helicobacter pylori infection in China

Background

The urea breath test (UBT) is widely used for diagnosing Helicobacter pylori infection. In the Shenzhen Kuichong People’s Hospital, some UBT findings were contradictory to the histology outcomes, therefore this study aimed to assess and compare the diagnostic performance of both ¹³C- and ¹⁴C-UBT assays.

Methods

We recruited 484 H. pylori-treatment naïve patients, among which 217 and 267 were tested by the ¹³C-UBT or ¹⁴C-UBT, respectively. The cutoff value for H. pylori positivity based on manufacturer’s instruction was 4% delta over baseline (DOB) for the ¹³C-UBT, and 100 disintegrations per minute (DPM) for the ¹⁴C-UBT. Gastric biopsies of the antrum and corpus were obtained during endoscopy for histopathology.

Results

In patients who were tested using the ¹³C-UBT kit, histopathology was positive in 136 out of 164 UBT-positive patients (82.9% concordance), and negative in 46 out of 53 UBT-negative cases (86.8% concordance). For the ¹⁴C-UBT-tested patients, histopathology was positive for H. pylori in 186 out of 220 UBT-positive patients (84.5% concordance), and negative in 41 out of 47 UBT-negative cases (87.2% concordance). While the ¹³C-UBT and ¹⁴C-UBT each had a high sensitivity level of 95.1% and 96.9%, respectively, their specificity was low, at 62.2% and 54.7%, respectively. By using new optimal cutoff values and including an indeterminate range (3–10.3% DOB for ¹³C-UBT and 87–237 DPM for ¹⁴C-UBT), the specificity values can be improved to 76.7% and 76.9% for the ¹³C- and ¹⁴C-UBT, respectively.

Conclusions

The establishment of an indeterminate range is recommended to allow for repeated testing to confirm H. pylori infection, and thereby avoiding unnecessary antibiotic treatment.

Trial registration: Chinese Clinical Trial Registry, ChiCTR2000041570. Registered 29 December 2020- Retrospectively registered, http://www.chictr.org.cn/edit.aspx?pid=66416&htm=4

Supplementary Information

The online version contains supplementary material available at 10.1186/s13099-021-00435-3.

Non-invasive diagnostic tests for Helicobacter pylori infection

BACKGROUND

Helicobacter pylori (H pylori) infection has been implicated in a number of malignancies and non-malignant conditions including peptic ulcers, non-ulcer dyspepsia, recurrent peptic ulcer bleeding, unexplained iron deficiency anaemia, idiopathic thrombocytopaenia purpura, and colorectal adenomas. The confirmatory diagnosis of H pylori is by endoscopic biopsy, followed by histopathological examination using haemotoxylin and eosin (H & E) stain or special stains such as Giemsa stain and Warthin-Starry stain. Special stains are more accurate than H & E stain. There is significant uncertainty about the diagnostic accuracy of non-invasive tests for diagnosis of H pylori.

OBJECTIVES

To compare the diagnostic accuracy of urea breath test, serology, and stool antigen test, used alone or in combination, for diagnosis of H pylori infection in symptomatic and asymptomatic people, so that eradication therapy for H pylori can be started.

SEARCH METHODS

We searched MEDLINE, Embase, the Science Citation Index and the National Institute for Health Research Health Technology Assessment Database on 4 March 2016. We screened references in the included studies to identify additional studies. We also conducted citation searches of relevant studies, most recently on 4 December 2016. We did not restrict studies by language or publication status, or whether data were collected prospectively or retrospectively.

SELECTION CRITERIA

We included diagnostic accuracy studies that evaluated at least one of the index tests (urea breath test using isotopes such as 13C or 14C, serology and stool antigen test) against the reference standard (histopathological examination using H & E stain, special stains or immunohistochemical stain) in people suspected of having H pylori infection.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the references to identify relevant studies and independently extracted data. We assessed the methodological quality of studies using the QUADAS-2 tool. We performed meta-analysis by using the hierarchical summary receiver operating characteristic (HSROC) model to estimate and compare SROC curves. Where appropriate, we used bivariate or univariate logistic regression models to estimate summary sensitivities and specificities.

MAIN RESULTS

We included 101 studies involving 11,003 participants, of which 5839 participants (53.1%) had H pylori infection. The prevalence of H pylori infection in the studies ranged from 15.2% to 94.7%, with a median prevalence of 53.7% (interquartile range 42.0% to 66.5%). Most of the studies (57%) included participants with dyspepsia and 53 studies excluded participants who recently had proton pump inhibitors or antibiotics.There was at least an unclear risk of bias or unclear applicability concern for each study.Of the 101 studies, 15 compared the accuracy of two index tests and two studies compared the accuracy of three index tests. Thirty-four studies (4242 participants) evaluated serology; 29 studies (2988 participants) evaluated stool antigen test; 34 studies (3139 participants) evaluated urea breath test-13C; 21 studies (1810 participants) evaluated urea breath test-14C; and two studies (127 participants) evaluated urea breath test but did not report the isotope used. The thresholds used to define test positivity and the staining techniques used for histopathological examination (reference standard) varied between studies. Due to sparse data for each threshold reported, it was not possible to identify the best threshold for each test.Using data from 99 studies in an indirect test comparison, there was statistical evidence of a difference in diagnostic accuracy between urea breath test-13C, urea breath test-14C, serology and stool antigen test (P = 0.024). The diagnostic odds ratios for urea breath test-13C, urea breath test-14C, serology, and stool antigen test were 153 (95% confidence interval (CI) 73.7 to 316), 105 (95% CI 74.0 to 150), 47.4 (95% CI 25.5 to 88.1) and 45.1 (95% CI 24.2 to 84.1). The sensitivity (95% CI) estimated at a fixed specificity of 0.90 (median from studies across the four tests), was 0.94 (95% CI 0.89 to 0.97) for urea breath test-13C, 0.92 (95% CI 0.89 to 0.94) for urea breath test-14C, 0.84 (95% CI 0.74 to 0.91) for serology, and 0.83 (95% CI 0.73 to 0.90) for stool antigen test. This implies that on average, given a specificity of 0.90 and prevalence of 53.7% (median specificity and prevalence in the studies), out of 1000 people tested for H pylori infection, there will be 46 false positives (people without H pylori infection who will be diagnosed as having H pylori infection). In this hypothetical cohort, urea breath test-13C, urea breath test-14C, serology, and stool antigen test will give 30 (95% CI 15 to 58), 42 (95% CI 30 to 58), 86 (95% CI 50 to 140), and 89 (95% CI 52 to 146) false negatives respectively (people with H pylori infection for whom the diagnosis of H pylori will be missed).Direct comparisons were based on few head-to-head studies. The ratios of diagnostic odds ratios (DORs) were 0.68 (95% CI 0.12 to 3.70; P = 0.56) for urea breath test-13C versus serology (seven studies), and 0.88 (95% CI 0.14 to 5.56; P = 0.84) for urea breath test-13C versus stool antigen test (seven studies). The 95% CIs of these estimates overlap with those of the ratios of DORs from the indirect comparison. Data were limited or unavailable for meta-analysis of other direct comparisons.

AUTHORS' CONCLUSIONS

In people without a history of gastrectomy and those who have not recently had antibiotics or proton ,pump inhibitors, urea breath tests had high diagnostic accuracy while serology and stool antigen tests were less accurate for diagnosis of Helicobacter pylori infection.This is based on an indirect test comparison (with potential for bias due to confounding), as evidence from direct comparisons was limited or unavailable. The thresholds used for these tests were highly variable and we were unable to identify specific thresholds that might be useful in clinical practice.We need further comparative studies of high methodological quality to obtain more reliable evidence of relative accuracy between the tests. Such studies should be conducted prospectively in a representative spectrum of participants and clearly reported to ensure low risk of bias. Most importantly, studies should prespecify and clearly report thresholds used, and should avoid inappropriate exclusions.

Helicobacter pylori infection is not associated with failure to thrive: a case control study

Purpose

The long-term impact of Helicobacter pylori infection is complex, and concerns about the need for eradication exist. We conducted this case control study to investigate the association between H. pylori infection and failure to thrive (FTT).

Patients and methods

From January 2009 to December 2011, 53 children with FTT group and matched children with the same sex and age and similar socioeconomic status without FTT (control group) were enrolled. A questionnaire was administered to the parents/guardian, and a ¹³C-urea breath test was performed to detect H. pylori infection.

Results

We found that the total prevalence of H. pylori infection was 29.2% and that there was no association between FTT and H. pylori infection (FTT group: 32%; control group: 26.4%; P=0.67). Short stature was more common in the FTT group and abdominal pain in the control group (FTT group: 37.7%; control group: 11.3%; P=0.003). In a comparison between the H. pylori-positive and -negative groups, abdominal pain (87.1% vs 64%; P=0.032) and the frequency of endoscopy (74.2% vs 32%; P<0.001) were significantly more common in the H. pylori-positive group.

Conclusion

We found that children with H. pylori infection are at an increased risk for abdominal pain and that FTT is not associated with H. pylori infection. The decision for eradication should be evaluated carefully and individualized.

Update on diagnostic value of breath test in gastrointestinal and liver diseases

In the field of gastroenterology, breath tests (BTs) are used intermittently as diagnostic tools that allow indirect, non-invasive and relatively less cumbersome evaluation of several disorders by simply quantifying the appearance in exhaled breath of a metabolite of a specific substrate administered. The aim of this review is to have an insight into the principles, methods of analysis and performance parameters of various hydrogen, methane and carbon BTs which are available for diagnosing gastrointestinal disorders such as Helicobacter pylori infection, small intestinal bacterial overgrowth, and carbohydrate malabsorption. Evaluation of gastric emptying is routinely performed by scintigraphy which is however, difficult to perform and not suitable for children and pregnant women, this review has abridged the 13C-octanoic acid test in comparison to scintigraphy and has emphasized on its working protocol and challenges. A new development such as electronic nose test is also highlighted. Moreover we have also explored the limitations and constraints restraining the wide use of these BT. We conclude that breath testing has an enormous potential to be used as a diagnostic modality. In addition it offers distinct advantages over the traditional invasive methods commonly employed.

Effect of posture on 13C-urea breath test in partial gastrectomy patients

AIM: To investigate whether posture affects the accuracy of ¹³C-urea breath test (¹³C-UBT) for Helicobacter pylori (H. pylori) detection in partial gastrectomy patients.

METHODS: We studied 156 consecutive residual stomach patients, including 76 with H. pylori infection (infection group) and 80 without H. pylori infection (control group). H. pylori infection was confirmed if both the rapid urease test and histology were positive during gastroscopy. The two groups were divided into four subgroups according to patients’ posture during the ¹³C-UBT: subgroup A, sitting position; subgroup B, supine position; subgroup C, right lateral recumbent position; and subgroup D, left lateral recumbent position. Each subject underwent the following modified ¹³C-UBT: 75 mg of ¹³C-urea (powder) in 100 mL of citric acid solution was administered, and a mouth wash was performed immediately; breath samples were then collected at baseline and at 5-min intervals up to 30 min while the position was maintained. Seven breath samples were collected for each subject. The cutoff value was 2.0‰.

RESULTS: The mean delta over baseline (DOB) values in the subgroups of the infection group were similar at 5 min (P > 0.05) and significantly higher than those in the corresponding control subgroups at all time points (P < 0.01). In the infection group, the mean DOB values in subgroup A were higher than those in other subgroups within 10 min and peaked at the 10-min point (12.4‰± 2.4‰). The values in subgroups B and C both reached their peaks at 15 min (B, 13.9‰± 1.5‰; C, 12.2‰± 1.7‰) and then decreased gradually until the 30-min point. In subgroup D, the value peaked at 20 min (14.7‰± 1.7‰). Significant differences were found between the values in subgroups D and B at both 25 min (t = 2.093, P = 0.043) and 30 min (t = 2.141, P = 0.039). At 30 min, the value in subgroup D was also significantly different from those in subgroups A and C (D vs C: t = 6.325, P = 0.000; D vs A: t = 5.912, P = 0.000). The mean DOB values of subjects with Billroth I anastomosis were higher than those of subjects with Billroth II anastomosis irrespectively of the detection time and posture (P > 0.05).

CONCLUSION: Utilization of the left lateral recumbent position during the procedure and when collecting the last breath sample may improve the diagnostic accuracy of the ¹³C-UBT in partial gastrectomy patients.

Helicobacter pylori infection influences the severity of thrombocytopenia and its treatment response in chronic hepatitis B patients with compensatory cirrhosis: A multicenter, observational study

The role of Helicobacter pylori (H. pylori) infection on thrombocytopenia in chronic hepatitis B (CHB) related compensatory cirrhotic patients is unknown. We conducted an observational study to determine whether H. pylori plays a role in these patients. A total of 255 patients from three centers in China were enrolled in the study. All patients received nucleoside analogs (NA) therapy and were screened for H. pylori infection. Patients were divided into three groups based on their H. pylori infection status and the therapy administered: patients without H. pylori infection who received NA therapy alone (N = 146); patients with H. pylori infection who received NA therapy alone (n = 48); and patients with H. pylori infection who received H. pylori eradication combined with NA therapy (N = 61). We observed that in CHB compensatory cirrhotic patients with H. pylori infection, the platelets count was significantly lower relative to uninfected patients (31 versus 60 × 10(9)/L, p < 0.01). During a 2-year follow-up, the elevation in platelet count was significantly higher in HBV/H. pylori co-infected patients who received the NA and H. pylori eradication treatment compared to the other two groups (p < 0.01). It suggested that H. pylori infection and eradication treatment combined with NA were independent risk factors associated with platelets response during treatment of thrombocytopenia in CHB compensatory cirrhosis (p < 0.01). In conclusion, H. pylori infection may associate with thrombocytopenia in CHB compensatory cirrhosis. H. pylori eradication combined with NA treatment may prove to be beneficial to CHB compensatory cirrhotic patients with thrombocytopenia who are infected with H. pylori.

Effect of gastric acidification on the (14)C-UBT HELIPROBE(®) accuracy during Pantoprazole treatment in Helicobacter pylori positive patients

The aim of this study was to evaluate the influence of using Citric Acid on false negative rates induced by PPIs during (14)C-UBT in dyspeptic patients with H. pylori infection. In a crossover randomized controlled clinical trial, one hundred dyspeptic patients (46 females and 54 males) with determined H. pylori infection who referred to gastrointestinal Outpatient Clinic of Razi Hospital-Rasht, Iran. All the patients underwent a (14)C-UBT HELIPROBE(®) baseline test and the positive ones entered the second phase. They were divided randomly to two groups and started PPIs treatment by Pantoprazole (20 mg/daily Pantozol(®) Nycomed Company) and underwent two other UBTs in days 12-13 and 14-15 with and without 4 grams Citric Acid. In group I who underwent UBT with Citric Acid in days 12-13 (UBT2) and UBT without Citric Acid in days 14-15 (UBT3), there was no significant difference between the UBT results with and without Citric Acid (P≥0.05). In group II who underwent UBT without Citric Acid in days 12-13 and UBT with Citric Acid in days 14-15, the false negative rates were not significantly different between UBT with and without Citric Acid (P≥0.05). In both groups the results of UBT without Citric Acid after Pantoprazole consumption didn't change significantly compared to the baseline UBT. Also the difference between the false negative rates of baseline UBT and UBT without citric acid was not significant (P>0.05). These results suggest that acidification of gastric environment during (14)C-UBT cannot prevent false negative results and do not increase the accuracy of the test in patients taking PPIs.

Cure of alopecia areata after eradication of Helicobacter pylori: a new association?

Alopecia areata is a disease of the hair follicles, with strong evidence supporting autoimmune etiology. Alopecia areata is frequently associated with immune-mediated diseases with skin manifestations such as psoriasis and lichen planus, or without skin manifestations such as autoimmune thyroiditis and idiopathic thrombocytopenic purpura. Helicobacter pylori (H. pylori) infection is present in around 50% of the world's population and has been associated with a variety of immune-mediated extra-digestive disorders including autoimmune thyroiditis, idiopathic thrombocytopenic purpura, and psoriasis. A case of a 43-year old man with an 8-mo history of alopecia areata of the scalp and beard is presented. The patient was being treated by a dermatologist and had psychiatric support, without any improvement. He had a history of dyspepsia and the urea breath test confirmed H. pylori infection. The patient went into remission from alopecia areata after H. pylori eradication. If such an association is confirmed by epidemiological studies designed for this purpose, new therapeutic options could be available for these patients, especially in areas where infection with H. pylori is highly prevalent.

Diagnosis of Helicobacter pylori

The different invasive and noninvasive diagnostic tests for Helicobacter pylori have been applied mainly in emerging countries. Molecular methods have been developed, especially a test for detection of H. pylori and its clarithromycin resistance directly from stools. The long-term effects of eradication on histologic lesions have been studied in a meta-analysis and the prognostic value of post-treatment in gastric mucosa-associated lymphoid tissue lymphoma has been assessed. An operating link for gastritis assessment (the OLGA staging) has also been published. Attempts to simplify the urea breath test protocol have been made, and new stool antigen tests have been proposed and compared to those previously available.