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The CPT® Code 87799 refers to a laboratory test designed for the detection of infectious agents through the analysis of nucleic acids, specifically DNA or RNA. This code is utilized when the infectious agent is not otherwise specified (NOS), meaning that the specific organism being tested for is not clearly defined within the coding guidelines. Examples of such organisms may include, but are not limited to, West Nile Virus, Human T-Lymphotropic Virus, Epstein Barr Virus, BK Virus, Adenovirus, Hepatitis E Virus, Parvovirus B19, and Human Herpesvirus 8. The procedure involves the use of a direct probe test, which identifies a unique nucleic acid sequence known as the target sequence of the suspected organism, provided it is present in the sample collected from blood, tissue, or other bodily fluids. The test employs a probe that is labeled with either fluorescent or chemiluminescent markers to facilitate the detection process. During the testing process, the sample is treated to release nucleic acids from the target organism, if it exists within the sample. The labeled probe then specifically binds to the target sequence, forming a stable hybrid that can be detected. Ribosomal RNA is often the focus of these tests due to its abundance in microorganisms, as it is typically present in thousands of copies compared to the limited copies of genomic DNA. In cases where enhanced sensitivity is required, an amplified probe technique is employed, which significantly increases the assay's sensitivity by exponentially multiplying the target sequence of the organism's DNA or RNA into millions of copies. The polymerase chain reaction (PCR) or reverse transcriptase polymerase chain reaction (RT-PCR) are the most commonly used amplification techniques. Following amplification, the replicated sequences are identified using labeled DNA probes. The quantification aspect of this test, as indicated by the CPT® Code 87799, provides an assessment of the number of microorganisms present in the sample, often utilizing quantitative or real-time PCR methods to amplify the nucleic acid segment and generate detailed reports documenting the absolute or relative amounts of the identified nucleic acid sequence.
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The CPT® Code 87799 is indicated for use in the detection of infectious agents that are not otherwise specified. This test is particularly relevant in cases where a patient presents with symptoms of an infectious disease, but the specific causative organism has not been identified. The following conditions may warrant the use of this test:
The procedure associated with CPT® Code 87799 involves several critical steps to ensure accurate detection and quantification of the infectious agent's nucleic acids. The following outlines the procedural steps:
After the completion of the procedure associated with CPT® Code 87799, the laboratory will analyze the results and generate a report detailing the findings. The report will include information on the presence and quantity of the infectious agent detected in the sample. It is essential for healthcare providers to review these results in conjunction with the patient's clinical presentation to determine the appropriate course of action. Follow-up care may be necessary based on the findings, and additional testing may be warranted if the results indicate the presence of a significant infectious agent. Proper documentation and communication of the results to the healthcare team are critical for ensuring timely and effective patient management.
| Short Descr | DETECT AGENT NOS DNA QUANT | Medium Descr | IADNA NOS QUANTIFICATION EACH ORGANISM | Long Descr | Infectious agent detection by nucleic acid (DNA or RNA), not otherwise specified; quantification, each organism | 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 | 3 | CCS Clinical Classification | 206 - Microscopic examination (bacterial smear, culture, toxicology) |
| 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. | 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 | 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. | GW | Service not related to the hospice patient's terminal condition | 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. | RT | Right side (used to identify procedures performed on the right side of the body) | 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. | XS | Separate structure, a service that is distinct because it was performed on a separate organ/structure | 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 | GZ | Item or service expected to be denied as not reasonable and necessary | 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. | AY | Item or service furnished to an esrd patient that is not for the treatment of esrd | GV | Attending physician not employed or paid under arrangement by the patient's hospice provider | LT | Left side (used to identify procedures performed on the left side of the body) | PN | Non-excepted service provided at an off-campus, outpatient, provider-based department of a hospital | Q1 | Routine clinical service provided in a clinical research study that is in an approved clinical research study | XE | Separate encounter, a service that is distinct because it occurred during a separate encounter | XP | Separate practitioner, a service that is distinct because it was performed by a different practitioner |
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| 2011-01-01 | Changed | Short description changed. |
| 2001-01-01 | Changed | Code description changed. |
| 1998-01-01 | Added | First appearance in code book in 1998. |
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