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The CPT® Code 86651 refers to a laboratory test specifically designed to measure antibodies related to California (La Crosse) encephalitis in either blood or cerebrospinal fluid (CSF). California encephalitis is caused by a mosquito-borne virus belonging to the bunyaviridae family, which typically results in a mild illness, particularly in children during the late summer months. The clinical presentation of this infection often includes symptoms such as a stiff neck and lethargy, which generally appear approximately one week following exposure to the virus and can persist for up to ten days. In some cases, patients may experience seizures either during the acute phase of the infection or as a long-term consequence of the disease. The laboratory test measures specific antibodies: a positive titer for immunoglobulin G (IgG) antibodies indicates either a current or past infection, while a positive titer for immunoglobulin M (IgM) antibodies, when coupled with clinical suspicion of California (La Crosse) viral infection, suggests a current or recent infection. To perform this test, a blood sample is collected through a separately reportable venipuncture, and if CSF is required, it is obtained via a separately reportable lumbar puncture. The testing of both serum and CSF samples is conducted using a semi-quantitative indirect fluorescent antibody technique, which allows for the detection and measurement of these specific antibodies.
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The procedure associated with CPT® Code 86651 is indicated for the evaluation of potential California (La Crosse) encephalitis infection. The following conditions and symptoms warrant the performance of this laboratory test:
The procedure for testing antibodies for California (La Crosse) encephalitis involves several key steps, which are outlined below:
After the procedure, patients may experience some discomfort at the venipuncture or lumbar puncture sites, which is typically mild and resolves quickly. It is important for healthcare providers to monitor patients for any adverse reactions following the lumbar puncture, such as headache or back pain. The results of the antibody testing will be interpreted in conjunction with clinical findings to determine the presence of current or past infection. Follow-up care may include additional diagnostic testing or treatment based on the results and the patient's clinical condition.
| Short Descr | ENCEPHALITIS CALIFORN ANTBDY | Medium Descr | ANTIBODY ENCEPHALITIS CALIFORNIA LA CROSSE | Long Descr | Antibody; encephalitis, California (La Crosse) | 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 |
| 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. | 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 |
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| 2013-01-01 | Changed | Short Descriptor changed. |
| 1993-01-01 | Added | First appearance in code book in 1993. |
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