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An immunoassay is a laboratory technique used to detect the presence of a specific chemical substance, known as an analyte, in a sample. This particular procedure, identified by CPT® Code 83516, is designed for the qualitative or semiquantitative assessment of analytes that are not related to infectious agents, meaning it does not focus on antibodies or antigens produced in response to infections. Instead, it targets various non-infectious substances that may indicate underlying health conditions. The immunoassay can be performed using a multiple-step method, which often enhances the accuracy and reliability of the test results. The range of conditions that can be evaluated through this testing includes, but is not limited to, celiac disease, which is an autoimmune disorder triggered by gluten; motor and sensory neuropathy, which affects the peripheral nervous system; Crohn's disease and other forms of inflammatory bowel disease, which cause chronic inflammation of the gastrointestinal tract; liver disease, which encompasses a variety of liver dysfunctions; and thyroid disease, which involves disorders of the thyroid gland. Specific examples of analytes that may be tested using this code include Asialo IgG and IgM, ganglioside IgG and IgM, and gliadin IgA and IgG. It is important to note that when multiple immunoglobulin classes or subclasses are tested, each one is reported separately. For instance, if both gliadin IgA and IgG are assessed, the code 83516 would be reported twice to reflect the testing of both substances. The qualitative aspect of the test indicates whether the analyte is present or absent, while the semiquantitative aspect provides an approximate measure of the analyte's concentration. This code is specifically utilized for tests employing a multistep method, distinguishing it from CPT® Code 83518, which is reserved for single-step methods like reagent strip tests.
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The immunoassay procedure identified by CPT® Code 83516 is indicated for the detection of various non-infectious analytes. The following conditions and symptoms may warrant the use of this testing method:
The procedure for conducting an immunoassay under CPT® Code 83516 involves several key steps that ensure accurate detection of the specified analyte. The following procedural steps outline the process:
Post-procedure care following the immunoassay testing under CPT® Code 83516 typically involves monitoring the patient for any immediate reactions to the sample collection, especially if blood was drawn. The results of the immunoassay will be reviewed by the healthcare provider, who will interpret the findings in the context of the patient's clinical history and symptoms. Depending on the results, further diagnostic testing or treatment may be recommended. It is essential for healthcare professionals to communicate the results to the patient and discuss any necessary follow-up actions or additional testing that may be required based on the findings of the immunoassay.
| Short Descr | IMMUNOASSAY NONANTIBODY | Medium Descr | IMMUNOASSAY ANALYTE QUAL/SEMIQUAN MULTIPLE STEP | Long Descr | Immunoassay for analyte other than infectious agent antibody or infectious agent antigen; qualitative or semiquantitative, multiple step method | 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) | Yes | 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 | 6 | CCS Clinical Classification | 233 - Laboratory - Chemistry and Hematology |
| 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. | QW | Clia waived test | 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. | RT | Right side (used to identify procedures performed on the right side of the body) | LT | Left side (used to identify procedures performed on the left side of the body) | XU | Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service | GA | Waiver of liability statement issued as required by payer policy, individual case | 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 | 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. | 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. | E2 | Lower left, eyelid | E4 | Lower right, eyelid | GZ | Item or service expected to be denied as not reasonable and necessary | XP | Separate practitioner, a service that is distinct because it was performed by a different practitioner | 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. | 95 | Synchronous telemedicine service rendered via a real-time interactive audio and video telecommunications system: synchronous telemedicine service is defined as a real-time interaction between a physician or other qualified health care professional and a patient who is located at a distant site from the physician or other qualified health care professional. the totality of the communication of information exchanged between the physician or other qualified health care professional and the patient during the course of the synchronous telemedicine service must be of an amount and nature that would be sufficient to meet the key components and/or requirements of the same service when rendered via a face-to-face interaction. modifier 95 may only be appended to the services listed in appendix p. appendix p is the list of cpt codes for services that are typically performed face-to-face, but may be rendered via a real-time (synchronous) interactive audio and video telecommunications system. | CC | Procedure code change (use 'cc' when the procedure code submitted was changed either for administrative reasons or because an incorrect code was filed) | E1 | Upper left, eyelid | E3 | Upper right, eyelid | G8 | Monitored anesthesia care (mac) for deep complex, complicated, or markedly invasive surgical procedure | GC | This service has been performed in part by a resident under the direction of a teaching physician | GT | Via interactive audio and video telecommunication systems | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | GW | Service not related to the hospice patient's terminal condition | GX | Notice of liability issued, voluntary under payer policy | KT | Beneficiary resides in a competitive bidding area and travels outside that competitive bidding area and receives a competitive bid item | P2 | A patient with mild systemic disease | PD | Diagnostic or related non diagnostic item or service provided in a wholly owned or operated entity to a patient who is admitted as an inpatient within 3 days | PO | Excepted service provided at an off-campus, outpatient, provider-based department of a hospital | Q4 | Service for ordering/referring physician qualifies as a service exemption | Q6 | Service furnished under a fee-for-time compensation arrangement by a substitute physician or by a substitute physical therapist furnishing outpatient physical therapy services in a health professional shortage area, a medically underserved area, or a rural area | QM | Ambulance service provided under arrangement by a provider of services | RE | Furnished in full compliance with fda-mandated risk evaluation and mitigation strategy (rems) | X5 | Diagnostic services requested by another clinician: for reporting services by a clinician who furnishes care to the patient only as requested by another clinician or subsequent and related services requested by another clinician; this modifier is reported for patient relationships that may not be adequately captured by the above alternative categories; reporting clinician service examples include but are not limited to, the radiologist's interpretation of an imaging study requested by another clinician | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter |
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| 2023-01-01 | Note | Medium description grammar correction |
| 2011-01-01 | Changed | Short description changed. |
| 2010-01-01 | Changed | Code description changed. |
| 1995-01-01 | Added | First appearance in code book in 1995. |
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