Test Id : HPRP
Helicobacter pylori with Clarithromycin Resistance Prediction, Molecular Detection, PCR, Tissue
Useful For
Suggests clinical disorders or settings where the test may be helpful
Aiding in the diagnosis of Helicobacter pylori infection and prediction of clarithromycin resistance or susceptibility directly from gastric biopsies
Highlights
This test detects the Helicobacter pylori 23S ribosomal RNA gene and the three most common 23S ribosomal RNA gene mutations (A2143G, A2142G, and A2142C) associated with resistance to clarithromycin.
Reflex Tests
Lists tests that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial tests.
| Test Id | Reporting Name | Available Separately | Always Performed |
|---|---|---|---|
| TISSR | Tissue Processing | No | No |
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
When this test is ordered, the reflex test may be performed at an additional charge.
For more information see Helicobacter pylori Diagnostic Algorithm.
Method Name
A short description of the method used to perform the test
Real-Time Polymerase Chain Reaction (PCR)
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
Clarithromycin
H pylori
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
When this test is ordered, the reflex test may be performed at an additional charge.
For more information see Helicobacter pylori Diagnostic Algorithm.
Specimen Type
Describes the specimen type validated for testing
Varies
Ordering Guidance
If testing directly from feces is desired, order HPFRP / Helicobacter pylori with Clarithromycin Resistance Prediction, Molecular Detection, PCR, Feces.
For more information see Helicobacter pylori Diagnostic Algorithm.
ORDER QUESTIONS AND ANSWERS
| Question ID | Description | Answers |
|---|---|---|
| HPS3 | Specimen Source |
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
The high sensitivity of amplification by polymerase chain reaction requires the specimen to be processed in an environment in which contamination of the specimen by Helicobacter pylori DNA is unlikely.
Submit only 1 of the following specimens:
Specimen Type: Fresh tissue or biopsy
Sources: Stomach (or duodenum)
Container/Tube: Sterile container
Specimen Volume: Entire collection or 5 mm (3) approximate size of a pencil eraser
Collection Instructions:
1. Collect fresh tissue specimen.
2. Submit tissue in a sterile container (without adding anything).
3. Refrigerate or freeze the specimen.
Specimen Stability Information: Refrigerated (preferred) 7 days/Frozen 7 days
Preferred:
Supplies: Tissue Block Container (T553)
Specimen Type: Formalin-fixed, paraffin-embedded (FFPE) tissue block
Sources: Stomach (or duodenum)
Container/Tube: Tissue block
Collection Instructions: Submit FFPE tissue block to be cut and returned.
Specimen Stability Information: Ambient (preferred)/Refrigerated
Acceptable:
Specimen Type: Formalin-fixed, paraffin-embedded (FFPE) tissue scroll
Sources: Stomach (or duodenum)
Container/Tube: Sterile container for each individual cut section (scroll)
Collection Instructions: Perform microtomy and prepare five separate 10-micron sections. Each section (scroll) must be placed in a separate sterile container for submission.
Specimen Stability Information: Ambient (preferred)/Refrigerated
Special Instructions
Library of PDFs including pertinent information and forms related to the test
Forms
If not ordering electronically, complete, print, and send Gastroenterology and Hepatology Test Request (T728) with the specimen.
Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
Fresh tissue or biopsy: 5 mm(3)
Formalin-fixed paraffin-embedded tissue block: One block
Formalin-fixed paraffin-embedded tissue scroll: Two 10-micron sections
Reject Due To
Identifies specimen types and conditions that may cause the specimen to be rejected
| Tissue in formalin formaldehyde, or acetone FFPE slides | Reject |
Specimen Stability Information
Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included
| Specimen Type | Temperature | Time | Special Container |
|---|---|---|---|
| Varies | Varies | ||
Useful For
Suggests clinical disorders or settings where the test may be helpful
Aiding in the diagnosis of Helicobacter pylori infection and prediction of clarithromycin resistance or susceptibility directly from gastric biopsies
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
When this test is ordered, the reflex test may be performed at an additional charge.
For more information see Helicobacter pylori Diagnostic Algorithm.
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Helicobacter pylori is a cause of peptic ulcer disease and, when left untreated, a risk factor for gastric cancer. H pylori diagnosis includes noninvasive tests (eg, stool polymerase chain reaction [PCR], urea breath test, stool antigen test) and tests requiring endoscopy to collect specimens for analysis. Several tests can be performed on gastric specimens, including H pylori PCR.
Antimicrobial resistance in H pylori is poorly studied but is rising, challenging its treatment. Assessment of antimicrobial resistance can guide treatment. Endoscopically collected gastric specimens can be cultured for H pylori and the recovered organism tested for phenotypic antimicrobial susceptibility. However, the organism can be difficult to isolate in culture, and even when isolated, may not amenable to phenotypic susceptibility testing due to its fastidious nature.
Clarithromycin resistance is most often associated with 23S ribosomal RNA (rRNA) gene mutations (particularly A2143G, A2142G/C). A systematic review and meta-analysis showed the sensitivity and specificity of detection of the H pylori A2142G/C and/or A2143G combination for prediction of clarithromycin resistance in H pylori in biopsy samples to be 96% each.
This test detects H pylori in gastric and duodenal biopsy specimens and, when detected, assesses for H pylori 23S rRNA gene mutations associated with clarithromycin resistance.
Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Not detected
Interpretation
Provides information to assist in interpretation of the test results
A ‘detected’ result indicates the presence of Helicobacter pylori 23S ribosomal RNA gene; also indicated is whether or not one the three most common 23S ribosomal RNA gene mutations (A2143G, A2142G/C) associated with clarithromycin resistance is detected.
A ‘not detected’ result for H pylori indicates the absence of detectable H pylori DNA but does not negate the presence of the organism and may occur due to inhibition of the polymerase chain reaction (PCR), sequence variability underlying primers or probes, or the presence of H pylori DNA in quantities less than the limit of detection of the assay.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Testing should be performed at least 4 weeks after completion of antibiotic (including bismuth) therapy and after proton pump inhibitor (PPI) or vonoprazan therapy has been withheld for 2 weeks. False-negative results may occur if testing occurs prior to these recommended timeframes. Histamine 2-receptor antagonists have been shown to slightly decrease the sensitivity of some Helicobacter pylori tests and, if possible, should be discontinued 2 weeks before testing. Antacids do not appear to impair test performance and may be taken until one day before testing.
Test results should be used as an aid in the diagnosis. The single assay should not be used as the only criterion to form a treatment decision; results of this test should be correlated with clinical presentation and results of other laboratory tests. A negative result does not negate the presence of the organism or active disease.
Potential cross-reactivity may occur with the following non-pylori Helicobacter species: Helicobacter acinonychis, Helicobacter cetorum, and Helicobacter mustalae (not been reported to cause disease in humans) and Helicobacter canis, Helicobacter cinaedi, Helicobacter bizzozeronii, and Helicobacter heilmannii (infrequently found in humans).
This assay examines the three most common 23S ribosomal RNA mutations associated with clarithromycin resistance. Other mechanisms of clarithromycin resistance are not assessed, nor are mechanisms of resistance to non-clarithromycin antimicrobial agents.
Supportive Data
During laboratory verification studies, limit of detection was established for all four targets (wild type, and clarithromycin conferring point mutations; A2143G, A2142G, A2142C) at single genomes/µl in both fresh tissue and formalin-fixed, paraffin-embedded (FFPE). Positive percent agreement was assessed using 56 FFPE gastric tissues known to contain Helicobacter pylori. The assay detected H pylori DNA in 53/56 (95% agreement) samples, with 18 samples predicted to be resistant to clarithromycin. Bi-directional Sanger sequencing confirmed the presence of mutations associated resistance to clarithromycin in all 18 samples, while all other samples displayed wild type. Negative percent agreement was assessed using 98 FFPE gastric tissues not known to contain H pylori. The assay did not detect H pylori DNA in any of the negative samples (100% agreement).
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Malfertheiner P, Megraud F, O'Morain CA, et al. Management of Helicobacter pylori infection--the Maastricht IV/Florence consensus report. Gut. 2012;61(5):646-664. doi:10.1136/gutjnl-2012-302084
2. Chen D, Cunningham SA, Cole N, Kohner PC, Mandrekar JN, Patel R. Phenotypic and molecular antimicrobial susceptibility of Helicobacter pylori. Antimicrob Agents Chemother. 2017;61(4):e02530-16. doi:10.1128/AAC.02530-16
3. Beckman E, Saracino I, Fiorini G, et al. A novel stool PCR test for Helicobacter pylori may predict Clarithromycin resistance and eradication of infection at a high rate. J Clin Microbiol. 2017;55(8):2400-2405
4. Marrero Rolon R, Cunningham SA, Mandrekar JN, Polo ET, Patel R: Clinical evaluation of a real-time PCR assay for simultaneous detection of Helicobacter pylori and genotypic markers of clarithromycin resistance directly from stool. J Clin Microbiol. 2021;59(5):e03040-20. doi:10.1128/JCM.03040-20
5. Savarino V, Tracci D, Dulbecco P, et al. Negative effect of ranitidine on the results of urea breath test for the diagnosis of Helicobacter pylori. AM J Gastroenterol. 2001;96(2):348-52. doi:10.1111/j.1572-0241.2001.03517.x
6. Chey WD, Grigorios L, Howden CW, Moss SF. ACG Clinical Guideline: Treatment of Helicobacter pylori infection. Am J Gastroenterol. 2017;112(2):p 212-239. doi:10.1038/ajg.2016.563
7. Jones NL, Koletzko S, Goodman K, et al. Joint ESPGHAN/NASPGHAN Guidelines for the Management of Helicobacter pylori in Children and Adolescents. J Pediatr Gastroenterol Nutr. 2017:64(6):991-1003. doi:10.1097/MPG.0000000000001594
8. Malfertheiner P, Megraud F, O'Morain CA, et al. Management of Helicobacter pylori infection-the Maastricht V/Florence Consensus Report. Gut. 2017;66(1):6-30. doi:10.1136/gutjnl-2016-312288
Method Description
Describes how the test is performed and provides a method-specific reference
Fresh tissue samples (approximately 2 x 2 x 5 mm) are placed in a polymerase chain reaction (PCR) Bead Tube containing Tris-EDTA buffer, and proteinase K and digested on the Bertin Precellys Disruptor. Formalin-fixed, paraffin-embedded (FFPE) tissue scrolls are placed in a PCR bead tube containing Tris-EDTA buffer and proteinase K and undergo a prolonged heat treatment for digestion. Once digested, samples undergo DNA extraction on a MagNA Pure 96 instrument. The PCR assay employs a target-specific detection system including primers as well TaqMan detection probes alongside a SimpleProbe for melt curve analysis-based genotyping targeting the 23S ribosomal RNA gene.
The LightCycler 480 II instrument is used to amplify and monitor target nucleic acid sequences by fluorescence during PCR cycling. Detection of amplified product is based on the TaqMan probe principle. For PCR product detection, the TaqMan probe binds the complementary strand of amplified target. Specific PCR Taq polymerase with 5'-3' exonuclease activity degrades the probe, releasing the fluorophore and breaking the proximity to the quencher molecule, allowing fluorescence of the fluorophores. At the conclusion of PCR cycling, amplified product is thermally denatured and then cooled to allow for a fluorescein labeled SimpleProbe to anneal to an 18-base pair region of the amplified target that includes 2 positions’ mutations which are known to confer clarithromycin resistance. The temperature is slowly raised, while consistently monitoring fluorescence. The process is completed in a closed system to mitigate contamination. Contamination control is enhanced using uracil -DNA glycosylase enzymatic treatment and a master mix which includes dUTPs.(Chen D, Cunningham SA, Cole NC, Kohner PC, Mandrekar JN, Patel R. Phenotypic and molecular antimicrobial susceptibility of Helicobacter pylori. Antimicrob Agents Chemother. 2017;61(4):e02530-16. doi: 10.1128/AAC.02530-16)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.
Monday through Friday
Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
Fees :
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.
- Authorized users can sign in to Test Prices for detailed fee information.
- Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
- Prospective clients should contact their account representative. For assistance, contact Customer Service.
Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.
CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
CPT codes are provided by the performing laboratory.
CPT codes are provided by the performing laboratory.
87513
LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.
| Test Id | Test Order Name | Order LOINC Value |
|---|---|---|
| HPRP | H pylori + Clarithro Resist, PCR | 88509-5 |
| Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
|---|---|---|
| HPS3 | Specimen Source | 31208-2 |
| 616027 | Helicobacter pylori Result | 91060-4 |
| 616028 | Clarithromycin Resistance Result | 88509-5 |