Best, 2018

SR and meta-analysis

Literature search up to 4 March 2016.

A: Behrens, 1999

B: Czerwionka-Szaflarska, 2007

C: Delvin, 1999

D: Dinler, 1999

E: Eltumi, 1999

F: Hafeez, 2007

G: Kalach, 1998

H: Kuloglu, 2008

I: Lottspeich, 2007

J: Ogata, 2001

K: Vandenplas, 1992

L: Yoshimura, 2001

Study design:

A: unclear

B: retrospective study

C: prospective study

D: unclear

E: prospective study

F: unclear

G: prospective study

H: prospective study

I: unclear

J: prospective study

K: unclear

L: unclear

Setting and Country:

A: secondary care, Germany

B: secondary care, Poland

C: secondary care, Canada

D: secondary care, Turkey

E: tertiary care, UK

F: secondary care, Pakistan

G: secondary care, France

H: secondary care, Turkey

I: secondary care, Germany

J: secondary care, Brazil

K: secondary care, Belgium

L: secondary care, Japan

Source of funding and conflicts of interest:

This report is independent research funded by the National Institute for Health Research (NIHR Cochrane Programme Grants, 13/89/03 - Evidence-based diagnosis and management of upper digestive, hepato-biliary, and pancreatic disorders). The views expressed in this publication are those of the author(s) and not necessarily those of the NHS, the National Institute for Health Research or the Department of Health.

Inclusion criteria SR:

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 (endoscopic biopsy with Haemotoxylin & Eosin stain, special stains, or combination of Haemotoxylin & Eosin and special stains) in people suspected of having H pylori infection. Regardless of language or publication status, or whether data were collected prospectively or retrospectively.

Exclusion criteria SR:

Reports that describe how the diagnosis of H pylori was made in an individual patient or group of patients, and which do not provide sufficient diagnostic test accuracy data (i.e. the number of true positives, false positives, false negatives, and true negatives. They also exclude case-control studies.

101 studies included (N=11,003), of which 12 studies (N=1,097) included only children.

N, mean age

A: 252; 3-18 years

B: 100; 13 years

C: 79; age not stated

D: 77; 13 years

E: 50; 11 years

F: 60; age not stated

G: 100; 11 years

H: 109; 12 years

I: 56; 10 years

J: 47; 12 years

K: 95; 9 years

L: 72; 13 years

Sex (% M):

A: -

B: 34% in total group

C: -

D: 37.7% in total group

E: 66% in total group

F: -

G: 65% in total group

H: 66.8% in total group

I: -

J: 42.6% in total group

K: 67.4% in total group

L: 52.8% in total group

Describe index and comparator tests* and

cut-off point(s):

A: urea breath test -13C (criteria for positive diagnosis: delta over baseline > 5.0% (30 minutes and 60 minutes))

B: urea breath test -13C (criteria for positive diagnosis: delta over baseline > 4.0 % (time not stated))

C: urea breath test -13C (Different criteria for positive diagnosis:

• Delta over baseline > 2.0% (30 minutes)
• Delta over baseline > 2.5% (30 minutes)
• Delta over baseline > 3.0% (30 minutes)
• Delta over baseline > 3.5% (30 minutes)
• Delta over baseline > 4.0% (30 minutes)
• Delta over baseline > 4.5% (30 minutes))

D: serology (Criteria for positive diagnosis: not stated)

E-1: urea breath test -13C (criteria for positive diagnosis: delta over baseline > 5 units/ml (40 minutes))

E-2: serology (criteria for positive diagnosis: not stated)

F-1: urea breath test -13C (criteria for positive diagnosis: delta over baseline > 4.0% (10 minutes, 20 minutes, and 30 minutes))

G: serology (Criteria for positive diagnosis: > 6 IU /ml)

H: urea breath test-14C (Criteria for positive diagnosis: Counts per minute > 50 (10 minutes))

I: urea breath test -13C (criteria for positive diagnosis: delta over baseline > 5.0% (30 minutes))

J-1: urea breath test -13C (criteria for positive diagnosis: 3% excretion (time not stated))

J-2: serology (criteria for positive diagnosis: 7 U/ml)

K-1: urea breath test -13C (criteria for positive diagnosis: not clearly stated)

K-2: serology (criteria for positive diagnosis:> Mean + 3 standard deviations above normal level)

L-1: urea breath test -13C (criteria for positive diagnosis: delta over baseline > 3.0% (20 minutes and 30 minutes))

L-2: serology (criteria for positive diagnosis: ≥ 1.8)

Describe reference test and cut-off point(s):

A: endoscopic biopsy with H & E stain

B: endoscopic biopsy with H & E stain

C: endoscopic biopsy with H & E stain and Warthin-Starry stain

D: endoscopic biopsy (staining not reported, probably H & E)

E: endoscopic biopsy with H & E stain and Warthin-Starry stain

F: endoscopic biopsy with Giemsa stain

G: endoscopic biopsy with H & E stain

H: endoscopic biopsy with H & E stain and Giemsa stain

I: endoscopic biopsy with H & E stain or Giemsa stain

J: endoscopic biopsy with H & E stain and Giemsa stain

K: endoscopic biopsy with H & E stain and Giemsa stain

L: endoscopic biopsy with H & E stain and Giemsa stain

Prevalence (%)

Not clearly described per study

For how many participants were no complete outcome data available?

Not clearly specified

Reasons for incomplete outcome data described?

Not clearly specified

Endpoint of follow-up:

Not clearly described per study

Outcome measures and effect size (include 95%CI and p-value if available):

Outcome measure-1/2

Sensitivity:

A: 0.95 (95% CI: 0.90, 0.98)

B: 0.68 (95% CI: 0.49, 0.83)

C: 1.00 (95% CI: 0.74, 1.00)

D: 0.83 (95% CI: 0.71, 0.91)

E-1: 0.89 (95% CI: 0.67, 0.99)

E-2: 0.95 (95% CI: 0.74, 1.00)

F: 0.91 (95% CI: 0.76, 0.98)

G: 0.84 (95% CI: 0.70, 0.93)

H: 0.93 (95% CI: 0.80, 0.98)

I: 1.00 (95% CI: 0.91, 1.00)

J-1: 0.96 (95% CI: 0.78, 1.00)

J-2: 1.00 (95% CI: 0.85, 1.00)

K-1: 0.89 (95% CI: 0.71, 0.98)

K-2: 0.89 (95% CI: 0.71, 0.98)

L-1: 0.95 (95% CI: 0.85, 0.99)

L-2: 0.93 (95% CI: 0.81, 0.99)

Specificity:

A: 0.93 (95% CI: 0.87, 0.97)

B: 0.93 (95% CI: 0.84, 0.98)

C: 1.00 (95% CI: 0.95, 1.00)

D: 0.42 (95% CI: 0.20, 0.67)

E-1: 0.90 (95% CI: 0.74, 0.98)

E-2: 0.81 (95% CI: 0.63, 0.93)

F: 0.60 (95% CI: 0.36, 0.81)

G: 0.88 (95% CI: 0.76, 0.95)

H: 0.86 (95% CI: 0.75, 0.93)

I: 1.00 (95% CI: 0.78, 1.00)

J-1: 0.67 (95% CI: 0.45, 0.84)

J-2: 0.67 (95% CI: 0.45, 0.84)

K-1: 0.93 (95% CI: 0.84, 0.98)

K-2: 0.96 (95% CI: 0.88, 0.99)

L-1: 0.89 (95% CI: 0.72, 0.98)

L-2: 0.89 (95% CI: 0.72, 0.98)

Pooled characteristic per index test and cut-off point:

Cannot be used for our review, because we are only interested in children and Best (2018) presents results for children and adults combined

Outcome measure-3

TP, FP, FN, TN:

A: 129, 7, 7, 98

B: ?, 5, 10, 64

C: 12, 0, 0, 67

D: 48, 11, 10, 8

E-1: 17, 3, 2, 28

E-2: 18, 6, 1, 25

F: 31, 8, 3, 12

G: 37, 7, 7, 49

H: 37, 10, 3, 59

I: 41, 0, 0, 15

J-1: 22, 8, 1, 16

J-2: 23, 8, 0, 16

K-1: 24, 5, 3, 63

K-2: 24, 3, 3, 65

L-1: 42, 3, 2, 25

L-2: 41, 3, 3, 25

Study quality (ROB):

Tool used by authors: QUADAS-2, see table “Risk of bias assessment diagnostic accuracy studies” for individual study qualifications

Place of the index test in the clinical pathway:

Not clearly described

Choice of cut-off point:

Not clearly described per study

Author’s conclusion

(for their whole study population, so not only in children) In people with no 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 had lower accuracy to detect H pylori infection. Although susceptible to bias due to confounding, this conclusion is based on evidence from indirect test comparisons, as evidence from direct comparisons was based on few studies or was unavailable. There was high or unclear risk of bias for many studies with respect to the selection of participants, and the conduct and interpretation of the index tests and reference standard. The thresholds used for these tests were highly variable, thus there is insufficient evidence to identify specific thresholds that might be useful in clinical practice.

Personal remarks on study quality, conclusions, and other issues (potentially) relevant to the research question

Limitations:

• heterogeneity in the thresholds used for the index tests and studies did not often prespecify or clearly report thresholds used.
• Risk of bias was generally high or unclear with respect to the selection of participants, and the conduct and interpretation of the index tests and reference standard.
• Applicability concerns were also generally high or unclear with respect to selection of participants.
• Additionally, the interval between the index test and reference standard was unclear for 10/12 (83%) studies in children

Feng, 2022

Type of study: Retrospective cohort

Setting and country: Children hospital’s outpatient department, China

Funding and conflicts of interest:

The authors declare that the research was conducted in the

absence of any commercial or financial relationships that could be construed as a

potential conflict of interest.

Inclusion criteria:

Patients aged between 6 and 18 years with H. pylori infection were referred for endoscopy due to gastrointestinal

symptoms, and who agreed to undergo both culture and genetic testing for CLA resistance were eligible for enrolment. Patients receiving tailored therapy based on traditional culture

(phenotype-guided therapy) or genetic testing (genotype-guided therapy) results were ultimately included.

Exclusion criteria:

use of antibiotics or bismuth agents within 4 weeks or proton pump inhibitors within 2 weeks before the examination;

previous eradication therapy;

allergies or contraindications to the therapeutic drugs in this study;

or complications with other chronic or serious diseases.

Number of patients

I: N=87

R: N=71

Prevalence:

100%

Mean age (SD):

I: 9.7 (2.6)

R: 10.2 (2.5)

Sex:

I: 66.7% M/ 33.3% F
R: 67.6% M/ 32.4% F

Deoxyribonucleic acid from gastric biopsies was extracted with the TIANamp Micro DNA Kit (DP316, Beijing, China). PCR-based amplification of the 23S rRNA was performed to detect CLA-resistant mutations (A2142G, A2142C, and A2143G). Primers as followed (Jieli Bio): forward, 1,820–1,839 (5’-CCCAGCGATGTGGTCCAG-3’) and reverse, 2,244–2,225 (5’-CTCCATAAGAGCCAAAGCCC-3’). Reaction in 25μl mixture contained 1 μl of template DNA (<1 ug), 1 μl of each primer (10μM), 22 μl of 1.1×T3 super PCR mix (Tsingke, TSE030) and conducted using the following program: 1 cycle at 98◦C for 3min, 35 cycles at 98◦C for 15 s, 65◦C for 15 s, and 72◦C

for 30 s and final 1 cycle at 72◦C for 7min. The 425-bp PCR products were sent to a biotechnology company for sequencing (ABI 3730XL, Jieli Bio). Finally, Chromas 2 software was used to analyze mutations at positions 2,142 and 2,143.

Cut-off point(s):

minimum inhibitory

concentration (MIC) > 0.5 mg/l

Culture

Cut-off point(s): NA

Time between the index test and reference test:

NA

For how many participants were no complete outcome data available?

0

Reasons for incomplete outcome data described?

NA

Eradication rate:

I: 92.0% (95% CI; 84.1% to 96.7%)

R: 70.4% (95% CI; 58.4% to 80.7%)

Scaletsky, 2011

Type of study: Retrospective cohort

Setting and country:

University hospital, Brazil

Funding and conflicts of interest:

This work was supported by Fundacão de Amparo a

Pesquisa do Estado de São Paulo.

Inclusion criteria: Children between 1-18 with dyspeptic symptoms

Exclusion criteria:

Patients previously treated for H.

pylori infections were not included

N=217 children

Prevalence: 20.7%

Mean age: 10 yrs; no SD reported

Sex: 51.6% M / 48.4% F

Helicobacter pylori ClariRes assay (Ingenetix, Vienna, Austria) is a novel commercially available real-time PCR assay allowing H. pylori detection and clarithromycin susceptibility testing in either gastric biopsy or stool specimens. ClariRes assay is a modified version of the biprobe 23S rRNA gene real-time PCR assay published by Schabereiter-Gurtner et al.

Cut-off point(s): NA

Culture

Cut-off point(s):

NA

Time between the index test and reference test:

NA

For how many participants were no complete outcome data available?

0

Reasons for incomplete outcome data described?

NA

Antibiotic resistance detection

Sensitivity: 83.3%

Specificity: 100%

Accuracy: 95.6%

Vecsei, 2011

Type of study: retrospective cohort study

Setting and country: pediatric hospital, Austria

Funding and conflicts of interest: Drs Hirschl and Makristathis have received

consultancy fees from Ingenetics.

Inclusion criteria: children after an initial course of tailored triple

eradication therapy.

Exclusion criteria: Previously treated children having failed 1 or more courses of therapy

N= 96

Prevalence of resistance: 16.7% 

Mean age ± SD: 10.8 y (3.8)

Sex: 48% M / 52% F

Other important characteristics:

Describe index test:

biopsy samples were homogenized and

cultured followed by antibiogram

Cut-off point(s): Breakpoints of resistance to clarithromycin, metronidazole,

amoxicillin, levofloxacin, tetracycline, and rifampin were minimal inhibitory concentration values of ≥1, 16, 4, 2, 2, and 4mg/mL, respectively.

Describe reference test:

Using 200 mg stool, DNA was extracted with a QIAamp DNA

Stool Mini Kit (Qiagen, Hilden, Germany) according to the

manufacturer’s instructions. Stool DNA extracts were analyzed by fluorescence resonance energy transfer real-time PCR and melting curve analysis (H pylori ClariRes assay, Ingenetix, Vienna, Austria) in combination with LightCycler-FastStart DNA Master SYBR Green I (Roche Molecular Biochemicals, Mannheim,

Germany). A DNA probe labeled with the fluorophore Cy5 includes the sites of the mutations on the H pylori 23S rRNA gene responsible for resistance to clarithromycin and has 100% homology to the

sensitive wild-type genotype.

Cut-off point(s):

A melting temperature

of 638C corresponds to the clarithromycin-sensitive wild-type genotype; in resistant genotypes the melting temperature is 548C for

mutationsA2142GandA2143Gand 588Cfor mutationA2142C.

Time between the index test and reference test:

Not reported

For how many participants were no complete outcome data available? Not reported

Reasons for incomplete outcome data described? NA

Eradication rate ratio: 0.94 (0.57 to 1.53)

Feng, 2022

Was a consecutive or random sample of patients enrolled?

Yes

Was a case-control design avoided?

Yes

Did the study avoid inappropriate exclusions?

Yes

Were the index test results interpreted without knowledge of the results of the reference standard?

Yes

If a threshold was used, was it pre-specified?

Yes

Is the reference standard likely to correctly classify the target condition?

Yes

Were the reference standard results interpreted without knowledge of the results of the index test?

Yes

Was there an appropriate interval between index test(s) and reference standard?

NA

Did all patients receive a reference standard?

Yes

Did patients receive the same reference standard?

Yes

Were all patients included in the analysis?

Yes

Are there concerns that the included patients do not match the review question?

No

Are there concerns that the index test, its conduct, or interpretation differ from the review question?

No

Are there concerns that the target condition as defined by the reference standard does not match the review question?

No

CONCLUSION:

Could the selection of patients have introduced bias?

RISK: LOW

CONCLUSION:

Could the conduct or interpretation of the index test have introduced bias?

RISK: LOW

CONCLUSION:

Could the reference standard, its conduct, or its interpretation have introduced bias?

RISK: LOW

CONCLUSION

Could the patient flow have introduced bias?

RISK: LOW

Scaletsky, 2011

Was a consecutive or random sample of patients enrolled?

Yes

Was a case-control design avoided?

Yes

Did the study avoid inappropriate exclusions?

Yes

Were the index test results interpreted without knowledge of the results of the reference standard?

Yes

If a threshold was used, was it pre-specified?

Yes

Is the reference standard likely to correctly classify the target condition?

Yes

Were the reference standard results interpreted without knowledge of the results of the index test?

Yes

Was there an appropriate interval between index test(s) and reference standard?

NA

Did all patients receive a reference standard?

Yes

Did patients receive the same reference standard?

Yes

Were all patients included in the analysis?

Yes

Are there concerns that the included patients do not match the review question?

No

Are there concerns that the index test, its conduct, or interpretation differ from the review question?

No

Are there concerns that the target condition as defined by the reference standard does not match the review question?

No

CONCLUSION:

Could the selection of patients have introduced bias?

RISK: LOW

CONCLUSION:

Could the conduct or interpretation of the index test have introduced bias?

RISK: LOW

CONCLUSION:

Could the reference standard, its conduct, or its interpretation have introduced bias?

RISK: LOW

CONCLUSION

Could the patient flow have introduced bias?

RISK: LOW

Best, 2018

A: Hafeez, 2007 (antigen test faeces)

B: Kuloglu, 2008 (antigen test faeces)

C: Lottspeich, 2007 (antigen test faeces)

D: Rafeey, 2007 (antigen test faeces)

E: Argentieri, 2007 (antigen test faeces)

Was a consecutive or random sample of patients enrolled?

A: no

B: no

C: no

D: no

E: no

Was a case-control design avoided?

A: yes

B: yes

C: yes

D: yes

E: yes

Did the study avoid inappropriate exclusions?

A: unclear

B: unclear

C: unclear

D: unclear

E: unclear

Were the index test results interpreted without knowledge of the results of the reference standard?

A: unclear

B: unclear

C: unclear

D: unclear

E: unclear

If a threshold was used, was it pre-specified?

A: unclear

B: unclear

C: unclear

D: unclear

E: unclear

Is the reference standard likely to correctly classify the target condition?

A: yes

B: no

C: no

D: yes

E: yes

Were the reference standard results interpreted without knowledge of the results of the index test?

A: unclear

B: yes

C: unclear

D: unclear

E: unclear

Was there an appropriate interval between index test(s) and reference standard?

A: yes

B: unclear

C: yes

D: unclear

E: unclear

Did all patients receive a reference standard?

Unclear

Did patients receive the same reference standard?

A: yes

B: yes

C: yes

D: yes

E: yes

Were all patients included in the analysis?

A: no

B: no

C: unclear

D: unclear

E: unclear

Are there concerns that the included patients do not match the review question?

Yes

Best (2018) includes all ages, while our guideline focuses on children

Are there concerns that the index test, its conduct, or interpretation differ from the review question?

No

Are there concerns that the target condition as defined by the reference standard does not match the review question?

No

CONCLUSION:

Could the selection of patients have introduced bias?

RISK: UNCLEAR

CONCLUSION:

Could the conduct or interpretation of the index test have introduced bias?

RISK: UNCLEAR

CONCLUSION:

Could the reference standard, its conduct, or its interpretation have introduced bias?

RISK: HIGH

CONCLUSION

Could the patient flow have introduced bias?

RISK: UNCLEAR

Author, year

Selection of participants

Was selection of exposed and non-exposed cohorts drawn from the same population?

Exposure

Can we be confident in the assessment of exposure?

Outcome of interest

Can we be confident that the outcome of interest was not present at start of study?

Confounding-assessment

Can we be confident in the assessment of confounding factors? 

Confounding-analysis

Did the study match exposed and unexposed for all variables that are associated with the outcome of interest or did the statistical analysis adjust for these confounding variables?

Assessment of outcome

Can we be confident in the assessment of outcome?

Follow up

Was the follow up of cohorts adequate? In particular, was outcome data complete or imputed?

Co-interventions

Were co-interventions similar between groups?

Overall Risk of bias

Vescei, 2011

Probably no

Reason: Inclusion and exclusion criteria may be related to outcome

Probably yes

Reason: Exposure was provided by pharmacy

Probably yes

Reason: Relevant methods were used to evaluate status of resistance

Probably no

Reason: only some confounders were measured

Definitely no

Reason: No adjustment was performed

Definitely yes

Reason: sensitive measurement was used

Probably yes

Reason: not reported

Probably yes

Reason: Not reported

Some concerns

Reference

Reason for exclusion

Angol DC, Ocama P, Ayazika Kirabo T, Okeng A, Najjingo I, Bwanga F. Helicobacter pylori from Peptic Ulcer Patients in Uganda Is Highly Resistant to Clarithromycin and Fluoroquinolones: Results of the GenoType HelicoDR Test Directly Applied on Stool. Biomed Res Int. 2017;2017:5430723. doi: 10.1155/2017/5430723. Epub 2017 May 7. PMID: 28555193; PMCID: PMC5438841.

Wrong design: no comparison

Güven B, Gülerman F, Kaçmaz B. Helicobacter pylori resistance to clarithromycin and fluoroquinolones in a pediatric population in Turkey: A cross-sectional study. Helicobacter. 2019 Jun;24(3):e12581. doi: 10.1111/hel.12581. Epub 2019 Apr 4. PMID: 30950125.

Wrong intervention: no faeces sample

Hansomburana P, Anantapanpong S, Sirinthornpunya S, Chuengyong K, Rojborwonwittaya J. Prevalence of single nucleotide mutation in clarithromycin resistant gene of Helicobacter pylori: a 32-months prospective study by using hybridization real time polymerase chain reaction. J Med Assoc Thai. 2012 Mar;95 Suppl 3:S28-35. PMID: 22619884.

Wrong population: adults

Kargar, Mohammad & Ghorbani-Dalini, Sadegh & Doosti, Abbas & Baghernejad, Maryam. (2011). Molecular assessment of clarithromycin resistant Helicobacter pylori strains using rapid and accurate PCR-RFLP method in gastric specimens in Iran. African Journal of Biotechnology. 10. 7675-7678.

Wrong population: adults

Khalifehgholi M, Shamsipour F, Ajhdarkosh H, Ebrahimi Daryani N, Pourmand MR, Hosseini M, Ghasemi A, Shirazi MH. Comparison of five diagnostic methods for Helicobacter pylori. Iran J Microbiol. 2013 Dec;5(4):396-401. PMID: 25848511; PMCID: PMC4385167.

Wrong population: adults

Leal YA, Cedillo-Rivera R, Simón JA, Velázquez JR, Flores LL, Torres J. Utility of stool sample-based tests for the diagnosis of Helicobacter pylori infection in children. J Pediatr Gastroenterol Nutr. 2011 Jun;52(6):718-28. doi: 10.1097/MPG.0b013e3182077d33. PMID: 21478757.

Wrong design: no comparison

Miendje Deyi VY, Burette A, Bentatou Z, Maaroufi Y, Bontems P, Lepage P, Reynders M. Practical use of GenoType® HelicoDR, a molecular test for Helicobacter pylori detection and susceptibility testing. Diagn Microbiol Infect Dis. 2011 Aug;70(4):557-60. doi: 10.1016/j.diagmicrobio.2011.05.002. Epub 2011 Jun 22. PMID: 21696906.

Wrong population: adults

Osaki T, Mabe K, Zaman C, Yonezawa H, Okuda M, Amagai K, Fujieda S, Goto M, Shibata W, Kato M, Kamiya S. Usefulness of detection of clarithromycin-resistant Helicobacter pylori from fecal specimens for young adults treated with eradication therapy. Helicobacter. 2017 Oct;22(5). doi: 10.1111/hel.12396. Epub 2017 May 22. PMID: 28544222.

Wrong population: adults

Vécsei A, Innerhofer A, Graf U, Binder C, Giczi H, Hammer K, Bruckdorfer A, Hirschl AM, Makristathis A. Helicobacter pylori eradication rates in children upon susceptibility testing based on noninvasive stool polymerase chain reaction versus gastric tissue culture. J Pediatr Gastroenterol Nutr. 2011 Jul;53(1):65-70. doi: 10.1097/MPG.0b013e318210586d. PMID: 21694538.

Wrong population: children already received treatment