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The CPT® Code 87324 refers to a laboratory test designed to detect the presence of Clostridium difficile toxin antigen in a fecal sample using various immunoassay techniques. Clostridium difficile, often abbreviated as C. difficile, is a bacterium that resides in the colon and can produce toxins that lead to serious gastrointestinal diseases, particularly when present in significant quantities. This organism is recognized as the leading cause of bacterial diarrhea among hospitalized patients and is frequently associated with the use of antimicrobial drugs, which can disrupt normal gut flora and allow C. difficile to proliferate. The test can be performed using several immunoassay methods, including enzyme immunoassay (EIA), enzyme-linked immunosorbent assay (ELISA), fluorescence immunoassay (FIA), and immunochemiluminometric assay (IMCA). In practice, a fecal sample is collected and either preserved in a fixative or sent fresh to the laboratory for analysis. The EIA and ELISA techniques are particularly sensitive, capable of detecting minute quantities of the antigen by utilizing a specific antibody that binds to the antigen in the sample. A secondary enzyme-labeled antibody is then introduced, which facilitates the detection of the antigen-antibody complex through a chromogenic reaction, resulting in a visible color change or fluorescence that indicates the presence of the toxin. The results can be reported as qualitative, indicating the presence or absence of the antigen, or semi-quantitative, providing a measure of the antigen concentration based on colorimetric readings. The FIA method employs a fluorescent compound to detect the binding of the detection antibody to the analyte, while the IMCA method utilizes antibodies tagged with a chemiluminescent substance to identify and quantify the antigen-antibody complex through emitted light. This comprehensive approach to testing is crucial for diagnosing infections caused by C. difficile and guiding appropriate treatment strategies.
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The CPT® Code 87324 is indicated for use in the detection of Clostridium difficile toxin antigen in patients who present with symptoms suggestive of a C. difficile infection. The following conditions may warrant the use of this test:
The procedure for conducting the test under CPT® Code 87324 involves several key steps to ensure accurate detection of the C. difficile toxin antigen:
After the completion of the test, the laboratory will analyze the results and report them to the requesting physician. If the test is positive for C. difficile toxin antigen, the physician may consider initiating appropriate treatment for the infection, which may include specific antibiotics. It is important for healthcare providers to monitor the patient for any signs of complications or worsening symptoms following the diagnosis. Additionally, infection control measures may be implemented to prevent the spread of C. difficile within healthcare settings, particularly in cases involving hospitalized patients.
| Short Descr | CLOSTRIDIUM AG IA | Medium Descr | IAAD IA CLOSTRIDIUM DIFFICILE TOXIN | Long Descr | 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; Clostridium difficile toxin(s) | 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) | T1H - Lab tests - other (non-Medicare fee schedule) | MUE | 2 | CCS Clinical Classification | 206 - Microscopic examination (bacterial smear, culture, toxicology) |
| 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. | 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. | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | 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. | GW | Service not related to the hospice patient's terminal condition | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | 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. | Q4 | Service for ordering/referring physician qualifies as a service exemption | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | 76 | Repeat procedure or service by same physician or other qualified health care professional: it may be necessary to indicate that a procedure or service was repeated by the same physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 76 to the repeated procedure or service. note: this modifier should not be appended to an e/m service. | AQ | Physician providing a service in an unlisted health professional shortage area (hpsa) | CR | Catastrophe/disaster related | GA | Waiver of liability statement issued as required by payer policy, individual case | GC | This service has been performed in part by a resident under the direction of a teaching physician | 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 | GZ | Item or service expected to be denied as not reasonable and necessary | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study |
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| 2022-01-01 | Changed | First appearance of change in codebook. |
| 2022-01-01 | Note | Grammatical correction. |
| 2021-01-01 | Changed | First appearance of change in CPT® Code Set. |
| 2020-10-06 | Changed | Code changed. |
| 2016-01-01 | Changed | Description Changed |
| 2011-01-01 | Changed | Short description changed. |
| 2007-01-01 | Changed | Code description changed. |
| 2001-01-01 | Changed | Code description changed. |
| 1998-01-01 | Added | First appearance in code book in 1998. |
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