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The CPT® Code 86331 refers to a specific immunodiffusion test known as gel diffusion, which is performed qualitatively to detect the presence of antibodies or antigens in a patient's serum. This test is particularly relevant in the context of hypersensitivity pneumonitis, a condition that arises from an immune response to inhaled organic antigens. The procedure involves measuring precipitation antibodies that are associated with this condition. The test is conducted using a method called the Ouchterlony technique, which allows for the qualitative assessment of these antibodies. In the context of hypersensitivity pneumonitis, the test includes various antigens such as Aspergillus fumigatus, Aureobasidium pullulans, and others, which are known to trigger immune responses in susceptible individuals. The presence of precipitation antibodies is typically indicative of active cases of hypersensitivity pneumonitis; however, it is important to note that these antibodies may also be found in asymptomatic individuals. Therefore, while a positive result can support a diagnosis in conjunction with a patient's clinical history and symptoms, a negative result does not definitively exclude the diagnosis of hypersensitivity pneumonitis. The blood sample required for this test is obtained through a venipuncture, which is a separately reportable procedure. The serum collected is then subjected to qualitative immunodiffusion to identify the presence of the relevant antibodies.
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The immunodiffusion test coded as CPT® 86331 is indicated for the evaluation of hypersensitivity pneumonitis. This condition is characterized by an immune response to inhaled organic antigens, and the test is performed to detect specific precipitation antibodies associated with this hypersensitivity. The following are the explicitly provided indications for this procedure:
The procedure for conducting the immunodiffusion test under CPT® 86331 involves several key steps, which are detailed as follows:
Post-procedure care following the immunodiffusion test coded as CPT® 86331 primarily involves monitoring the patient for any immediate complications related to the venipuncture, such as bleeding or discomfort at the puncture site. Patients are typically advised to keep the area clean and dry. The results of the test will be communicated to the healthcare provider, who will interpret the findings in conjunction with the patient's clinical history and symptoms. It is important to note that while a positive test result can aid in the diagnosis of hypersensitivity pneumonitis, a negative result does not rule out the condition, and further evaluation may be necessary based on the patient's overall clinical picture.
| Short Descr | IMMUNODIFFUSION OUCHTERLONY | Medium Descr | IMMUNODIFFUSION GEL DIFFUSION QUAL EA AG/ANTBDY | Long Descr | Immunodiffusion; gel diffusion, qualitative (Ouchterlony), each antigen or antibody | 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 | 12 | CCS Clinical Classification | 235 - Other Laboratory |
| 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. | GA | Waiver of liability statement issued as required by payer policy, individual case | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | Q4 | Service for ordering/referring physician qualifies as a service exemption | GW | Service not related to the hospice patient's terminal condition | GZ | Item or service expected to be denied as not reasonable and necessary |
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| Pre-1990 | Added | Code added. |
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