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The CPT® Code 86364 refers to the tissue transglutaminase test, which is a specific immunological assay used to detect antibodies against tissue transglutaminase (tTG) in various immunoglobulin classes, primarily IgA and IgG. This test is particularly significant in the evaluation of celiac disease, a chronic autoimmune disorder triggered by the ingestion of gluten, a protein found in wheat, barley, rye, and oats. In individuals with celiac disease, the immune system mistakenly identifies gluten and tissue transglutaminase as harmful substances, leading to the production of autoantibodies. This immune response results in damage to the intestinal villi, which are small finger-like projections in the lining of the small intestine that play a crucial role in nutrient absorption. The damage to these villi can lead to malabsorption of essential nutrients, resulting in various gastrointestinal and systemic symptoms. Common symptoms associated with celiac disease include recurring abdominal pain, bloating, chronic diarrhea or constipation, weight loss, and iron deficiency anemia. The tTG antibody test is particularly valuable because it is highly sensitive, especially the tTG-IgA variant, which is the preferred test for diagnosing celiac disease in most patients. It is important to note that accurate test results require the patient to be on a gluten-containing diet, as the absence of gluten can lead to a lack of antibody production, rendering the test ineffective.
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The tissue transglutaminase test (CPT® Code 86364) is indicated for the evaluation of celiac disease, also known as celiac sprue. The following conditions and symptoms warrant the performance of this test:
The procedure for conducting the tissue transglutaminase test involves several key steps to ensure accurate results:
After the tissue transglutaminase test is performed, the patient may not require any specific post-procedure care. However, it is essential to discuss the results with the healthcare provider to understand the implications. If the test indicates the presence of antibodies, further evaluation or a biopsy may be recommended to confirm the diagnosis of celiac disease. Patients should also be advised to continue their gluten-containing diet until testing is complete, as removing gluten can lead to a decrease in antibody levels, potentially affecting the accuracy of the test results.
| Short Descr | TISS TRNSGLTMNASE EA IG CLAS | Medium Descr | TISSUE TRANSGLUTAMINASE EA IMMUNOGLOBULIN CLASS | Long Descr | Tissue transglutaminase, each immunoglobulin (Ig) class | Status Code | Statutory Exclusion (from MPFS, may be paid under other methodologies) | Global Days | XXX - Global Concept Does Not Apply | PC/TC Indicator (26, TC) | 9 - Not Applicable | Multiple Procedures (51) | 9 - Concept does not apply. | Bilateral Surgery (50) | 9 - Concept does not apply. | Physician Supervisions | 09 - Concept does not apply. | Assistant Surgeon (80, 82) | 9 - Concept does not apply. | Co-Surgeons (62) | 9 - Concept does not apply. | Team Surgery (66) | 9 - Concept does not apply. | Diagnostic Imaging Family | 99 - Concept Does Not Apply | CLIA Waived (QW) | No | APC Status Indicator | Conditionally packaged laboratory tests | Type of Service (TOS) | 5 - Diagnostic Laboratory | Berenson-Eggers TOS (BETOS) | none | MUE | 3 |
| 90 | Reference (outside) laboratory: when laboratory procedures are performed by a party other than the treating or reporting physician or other qualified health care professional, the procedure may be identified by adding modifier 90 to the usual procedure number. | 91 | Repeat clinical diagnostic laboratory test: in the course of treatment of the patient, it may be necessary to repeat the same laboratory test on the same day to obtain subsequent (multiple) test results. under these circumstances, the laboratory test performed can be identified by its usual procedure number and the addition of modifier 91. note: this modifier may not be used when tests are rerun to confirm initial results; due to testing problems with specimens or equipment; or for any other reason when a normal, one-time, reportable result is all that is required. this modifier may not be used when other code(s) describe a series of test results (eg, glucose tolerance tests, evocative/suppression testing). this modifier may only be used for laboratory test(s) performed more than once on the same day on the same patient. | 59 | Distinct procedural service: under certain circumstances, it may be necessary to indicate that a procedure or service was distinct or independent from other non-e/m services performed on the same day. modifier 59 is used to identify procedures/services, other than e/m services, that are not normally reported together, but are appropriate under the circumstances. documentation must support a different session, different procedure or surgery, different site or organ system, separate incision/excision, separate lesion, or separate injury (or area of injury in extensive injuries) not ordinarily encountered or performed on the same day by the same individual. however, when another already established modifier is appropriate it should be used rather than modifier 59. only if no more descriptive modifier is available, and the use of modifier 59 best explains the circumstances, should modifier 59 be used. note: modifier 59 should not be appended to an e/m service. to report a separate and distinct e/m service with a non-e/m service performed on the same date, see modifier 25. | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | GY | Item or service statutorily excluded, does not meet the definition of any medicare benefit or, for non-medicare insurers, is not a contract benefit | 26 | Professional component: certain procedures are a combination of a physician or other qualified health care professional component and a technical component. when the physician or other qualified health care professional component is reported separately, the service may be identified by adding modifier 26 to the usual procedure number. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | GA | Waiver of liability statement issued as required by payer policy, individual case | GW | Service not related to the hospice patient's terminal condition | GZ | Item or service expected to be denied as not reasonable and necessary | SA | Nurse practitioner rendering service in collaboration with a physician | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure |
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| 2022-01-01 | Added | Code added |
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