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The CPT® Code 86648 refers to a laboratory test specifically designed to measure the presence of antibodies against Diphtheria. Diphtheria is an acute and highly contagious disease caused by the bacterium Corynebacterium diphtheriae, which is known to produce an exotoxin. This toxin can lead to the formation of fibrinous pseudomembranes in various tissues, including respiratory, myocardial, and neural tissues, potentially resulting in severe complications. The antibody test for Diphtheria primarily measures the IgG subclass I, which is crucial for evaluating an individual's immune response. This test can serve multiple purposes: it may be utilized to determine a person's protective antibody levels before and after vaccination, assess immunity status during an outbreak in the community, or evaluate for possible antibody deficiencies in patients who experience recurrent infections. To perform this test, a blood sample is collected through venipuncture, which is a separately reportable procedure. The serum obtained from the blood sample is then analyzed using an enzyme immunoassay, a method that allows for the accurate measurement of the Diphtheria antibodies present in the serum.
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The Diphtheria antibody test (CPT® Code 86648) is indicated for several specific clinical scenarios, including:
The procedure for conducting the Diphtheria antibody test involves several key steps, which are outlined as follows:
After the Diphtheria antibody test is completed, there are generally no specific post-procedure care requirements for the patient. However, it is advisable for the patient to monitor the venipuncture site for any signs of complications, such as excessive bleeding, swelling, or infection. If any unusual symptoms occur, the patient should contact their healthcare provider. The results of the test will typically be available within a few days, and the physician will discuss the findings with the patient, including any necessary follow-up actions based on the antibody levels detected.
| Short Descr | DIPHTHERIA ANTIBODY | Medium Descr | ANTIBODY DIPHTHERIA | Long Descr | Antibody; Diphtheria | 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. | GA | Waiver of liability statement issued as required by payer policy, individual case | GZ | Item or service expected to be denied as not reasonable and necessary |
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| 1993-01-01 | Added | First appearance in code book in 1993. |
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