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The CPT® Code 86788 refers to the laboratory test that detects the presence of immunoglobulin M (IgM) antibodies specific to the West Nile virus. This test is crucial for diagnosing recent infections with the West Nile virus, particularly in patients exhibiting symptoms consistent with viral infection. The IgM antibodies are typically present in the blood serum or cerebrospinal fluid (CSF) of individuals who have been infected with the virus, and their detection is a key indicator of an active or recent infection. The testing process involves collecting samples of blood serum or CSF, ideally between 8 to 21 days after the onset of symptoms, to ensure accurate results. For confirmation of the diagnosis, serum samples are often tested at least two weeks apart, during both the acute and convalescent phases of the illness. The most reliable method for detecting IgM antibodies in CSF is through the MAC-ELISA (IgM antibody capture enzyme-linked immunosorbent assay) technique, as the presence of IgM in CSF indicates that the antibodies have crossed the blood-brain barrier, confirming a central nervous system infection. Additionally, plaque-reduction neutralizing tests can be performed on paired serum or CSF samples taken at least two weeks apart, with a four-fold increase in antibody titer serving as further confirmation of West Nile virus infection.
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The antibody test for West Nile virus, coded as CPT® 86788, is indicated for the following conditions:
The procedure for testing IgM antibodies to the West Nile virus involves several key steps:
After the procedure, it is important to monitor the patient for any potential side effects from the sample collection, particularly if CSF was obtained. Patients may experience mild discomfort or headache following a lumbar puncture. The results of the antibody tests will typically be reviewed by the healthcare provider to determine the appropriate course of action based on the presence of IgM antibodies and the clinical context. Follow-up testing may be necessary to assess the progression of the infection or the patient's recovery.
| Short Descr | WEST NILE VIRUS AB IGM | Medium Descr | ANTIBODY WEST NILE VIRUS IGM | Long Descr | Antibody; West Nile virus, IgM | 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 | 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. | 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. | 77 | Repeat procedure by another physician or other qualified health care professional: it may be necessary to indicate that a basic procedure or service was repeated by another physician or other qualified health care professional subsequent to the original procedure or service. this circumstance may be reported by adding modifier 77 to the repeated procedure or service. note: this modifier should not be appended to an e/m 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. | 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 | Q4 | Service for ordering/referring physician qualifies as a service exemption |
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| 2011-01-01 | Changed | Short description changed. |
| 2007-01-01 | Added | First appearance in code book in 2007. |
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