Gastroenterology Coding Alert

See which test codes apply to the 2023 CRC screening update.

You may feel you have a good handle on upper and lower GI procedures, but what about the rest of the tests your gastroenterologist uses to investigate the cause of a patient’s symptoms? After all, there’s more to GI coding than endoscopies and colonoscopies.

If you feel like your testing code knowledge is constantly being tested, here is a comprehensive primer on some common GI testing codes for you to take back to your practice.

Understand H. Pylori and Breath Tests

H. pylori is the bacteria responsible for causing gastritis and peptic (gastric and duodenal) ulcers. While a gastroenterologist can, and may sometimes, confirm an H. pylori infection through endoscopy with biopsy in some cases, breath tests are a non-invasive method of detecting the presence of the bacteria.

There are two types of breath tests: the carbon-13 (C-13) and carbon-14 (C-14) versions. To help you decipher the documentation and correctly identify the tests, here’s a refresher of what each test entails.

C-13: With the C-13 breath test, the lab tech takes a baseline breath sample from the patient and then gives liquid C-13 to the patient to swallow. Approximately 30 minutes later, the tech takes another breath sample, which your provider or the administering lab will analyze.

Coding: The physician or lab performing the C-13 test should bill code 83014 (Helicobacter pylori; drug administration). And whoever performs the analysis of the C-13 sample should report code 83013 (Helicobacter pylori; breath test analysis for urease activity, non-radioactive isotope (eg, C-13)).

“For the most part, patients are sent to commercial labs, and it is there that a provider will perform the breath tests. But there are some practices that administer the C-13 material, collect breath samples, and send to the lab for analysis,” says Glenn D. Littenberg, MD, MACP, FASGE, AGAF, a gastroenterologist and former CPT^® Editorial Panel advisor for ASGE in Pasadena, California.

The diagnostic codes you’ll report for the test before the result is known usually reflects the patient’s symptoms, such as epigastric pain, which codes to R10.13 (Epigastric pain) or dyspepsia, which codes to  K30 (Functional dyspepsia). “If the billing is done after a positive test result, then the ICD-10 codes could include either or both codes for the H. pylori infection itself with B96.81 [Helicobacter pylori (H. pylori)] as the cause of diseases classified elsewhere] and for the gastritis it causes with K29.0- [Acute gastritis],” according to Littenberg.

C-14: For the C-14 breath test, the patient gives a breath sample by blowing into a balloon 10 minutes after ingesting a capsule that contains a low dosage of a radioactive isotope. The provider ordering the test or the lab can then perform an analysis of the sample using a device called a liquid scintillation counter.

Coding: If your provider administers the C-14 breath test, you should use 78267 (Urea breath test, C-14 (isotopic); acquisition for analysis). The physician or lab that performs the analysis of the C-14 breath sample should report code 78268 (Urea breath test, C-14 (isotopic); analysis).

If the gastroenterologist performs both the administration and analysis of the tests, then he or she would report both codes depending on which test is performed.

Pediatric coding alert: The FDA has only cleared the urea breath test for use in patients over the age of 18, so the gastroenterologist may perform stool antigen testing for pediatric patients, which is billable using 87338 (Infectious agent antigen detection by immunoassay technique (eg, enzyme immunoassay [EIA], enzyme-linked immunosorbent assay [ELISA], fluorescence immunoassay [FIA], immunochemiluminometric assay [IMCA]), qualitative or semiquantitative; Helicobacter pylori, stool).

Remember Fecal Occult Tests for CRC Screenings

If you haven’t already, you may start seeing more fecal tests due to Medicare’s updated 2023 policy on colorectal cancer (CRC) screenings. As of Jan. 1, 2023, if a patient’s non-invasive stool-based test yields a positive result, Medicare views the follow-up colonoscopy as a preventative service. This eliminates the out-of-pocket cost for both tests. Here are the tests you may be seeing more of going forward:

• Screening guaiac-based fecal occult blood test (gFOBT), CPT^® 82270 (Blood, occult, by peroxidase activity (eg, guaiac), qualitative; feces, consecutive collected specimens with single determination, for colorectal neoplasm screening (ie, patient was provided 3 cards or single triple card for consecutive collection)). “This test and the billing for it applies to diagnostic rather than screening situations. For example, the doctor would perform this test for a patient with a history of black stools or who is anemic for reasons which may or may not be due to occult GI blood loss,” explains Littenberg.
• Screening immunoassay-based fecal occult blood test (iFOBT), HCPCS G0328 (Colorectal cancer screening; fecal occult blood test, immunoassay, 1-3 simultaneous).
• Cologuard™ – multi-target stool DNA (sDNA) test, CPT^® 81528 (Oncology (colorectal) screening, quantitative real-time target and signal amplification of 10 DNA markers (KRAS mutations, promoter methylation of NDRG4 and BMP3) and fecal hemoglobin, utilizing stool, algorithm reported as a positive or negative result).

Be Aware of Reflux Tests

Doctors typically perform impedance tests to measure and assess the flow of liquids and gases in the esophagus. A gastroenterologist will turn to these tests when they suspect conditions such as gastroesophageal reflux disease (GERD) or dysphagia.

Impedance Testing: During an impedance test, the provider inserts a catheter transnally into the patient’s body. This test measures bolus transit dynamics with either pH measurement or esophageal muscular function in the evaluation of symptoms including chest pain, swallowing difficulty, or chronic heartburn unresponsive to medication. Sometimes, physicians perform these tests in combination with motility study (manometry) or pH testing.

Coding: When reporting esophageal function (impedance) tests, you have two main codes to choose from:

• 91037 (Esophageal function test, gastroesophageal reflux test with nasal catheter intraluminal impedance electrode(s) placement, recording, analysis and interpretation)
• 91038 (… prolonged (greater than 1 hour, up to 24 hours))

Note that the descriptor for 91038 includes time parameters. This means you should choose 91037 for testing that lasts up to one hour. If the monitoring spans more than an hour, you should bill 91038 instead. However, you shouldn’t report both codes for the same test; you should only apply a single code to report the session. “Most commonly, the physician would perform the more prolonged test,” explains Littenberg.

Catheter-based pH testing: The doctor will sometimes also perform pH testing to measure the level of acidity or alkalinity in the esophagus, which provides valuable supplemental information about acid reflux. When a gastroenterologist provides an esophageal acid reflux test using either a disposable or a reusable nasal catheter, you should report 91034 (Esophagus, gastroesophageal reflux test; with nasal catheter pH electrode(s) placement, recording, analysis and interpretation).

Tip: Make 91034 your go-to code regardless of how long the nasal catheter remains in place. Typically, however, the physician will leave the catheter in place for about a day. In the past, you had to distinguish between standard and “extended” pH monitoring. Currently, only one code (91034) describes a catheter-based pH service.

On the other hand, if your gastroenterologist conducts pH testing using a Bravo capsule, you will turn to 91035 (Esophagus, gastroesophageal reflux test; with mucosal attached telemetry pH electrode placement, recording, analysis and interpretation) instead of 91034.

NCCI edit alert: Codes 91038 and 91034 are bundled, according to National Correct Coding Initiative (NCCI) edits. Check out the NCCI edits table, and you’ll see 91034 described as the more extensive code. Since the 91038/91034 edit carries a modifier indicator of “0,” you cannot override the edit by using a modifier such as 59 (Distinct procedural service).

For that reason, you would bill the given scenario with only 91034. Link R12 (Heartburn) to 91034 to describe the patient’s condition.