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Official Description

Infectious agent detection by nucleic acid (DNA or RNA); influenza virus, for multiple types or sub-types, includes multiplex reverse transcription, when performed, and multiplex amplified probe technique, each additional influenza virus type or sub-type beyond 2 (List separately in addition to code for primary procedure)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 87503 pertains to the detection of infectious agents through nucleic acid testing, specifically targeting the influenza virus. This test is designed to identify multiple types or subtypes of the influenza virus present in a laboratory specimen. Influenza viruses are categorized primarily into two main types: type A and type B. Within these categories, there are various subtypes, such as H1N1, H3N2, and H5N1, which can significantly impact public health. The process of nucleic acid detection involves extracting DNA or RNA from the specimen, which may include blood or other biological materials. The test utilizes advanced techniques such as multiplex reverse transcription, when applicable, and multiplex amplified probe techniques to enhance the accuracy and efficiency of the detection process. By employing reverse transcription polymerase chain reaction (RT-PCR), the test amplifies the extracted nucleic acids, allowing for precise identification of specific strains of the influenza virus. This coding is essential for accurate billing and documentation, as it distinguishes between different testing scenarios: CPT® Code 87501 is used for testing a single type or subtype, CPT® Code 87502 is designated for multiplex testing of the first two types or subtypes, and CPT® Code 87503 is specifically for each additional influenza type or subtype beyond the initial two tested.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The CPT® Code 87503 is indicated for the detection of multiple types or subtypes of the influenza virus in patients presenting with symptoms consistent with influenza infection. This test is particularly useful in the following scenarios:

  • Acute Respiratory Illness Patients exhibiting symptoms such as fever, cough, sore throat, body aches, and fatigue that may suggest an influenza infection.
  • Outbreak Situations In cases of suspected influenza outbreaks, this test aids in identifying the specific strains circulating within a population.
  • High-Risk Populations Individuals in high-risk groups, such as the elderly, young children, or those with compromised immune systems, may require precise identification of influenza subtypes for appropriate management.

2. Procedure

The procedure for CPT® Code 87503 involves several critical steps to ensure accurate detection of the influenza virus. The following outlines the procedural steps:

  • Specimen Collection A biological specimen, typically a nasopharyngeal swab, throat swab, or other respiratory sample, is collected from the patient. This specimen serves as the source for nucleic acid extraction.
  • Nucleic Acid Extraction The collected specimen undergoes a process to extract the nucleic acids (DNA or RNA) from the viral particles present in the sample. This step is crucial for isolating the genetic material of the influenza virus.
  • Reverse Transcription (if performed) If applicable, the extracted RNA is converted into complementary DNA (cDNA) through a process known as reverse transcription. This step is essential for amplifying the viral genetic material.
  • Multiplex Amplification The cDNA is then subjected to multiplex amplification techniques, which allow for the simultaneous detection of multiple influenza virus types or subtypes. This is achieved using specific primers that target the genetic sequences of the influenza viruses.
  • Analysis and Identification The amplified DNA or RNA fragments are analyzed to determine the presence of specific influenza virus types or subtypes. This analysis provides the necessary information for accurate diagnosis and treatment.

3. Post-Procedure

After the completion of the testing procedure associated with CPT® Code 87503, the laboratory will provide results that indicate the specific types or subtypes of influenza detected in the specimen. Clinicians will use these results to guide treatment decisions and public health responses. It is important for healthcare providers to communicate the results to the patient and discuss any necessary follow-up actions, such as antiviral treatment or preventive measures. Additionally, proper documentation of the test results and the corresponding CPT® codes is essential for accurate billing and reimbursement processes.

Short Descr INFLUENZA DNA AMP PROB ADDL
Medium Descr NFCT AGENT DNA/RNA INFLUENZA >2 TYPES EA ADDL
Long Descr Infectious agent detection by nucleic acid (DNA or RNA); influenza virus, for multiple types or sub-types, includes multiplex reverse transcription, when performed, and multiplex amplified probe technique, each additional influenza virus type or sub-type beyond 2 (List separately in addition to code for primary procedure)
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 1
CCS Clinical Classification 206 - Microscopic examination (bacterial smear, culture, toxicology)

This is an add-on code that must be used in conjunction with one of these primary codes.

87502 MPFS Status: Statutory exclusion (from MPFS, may be paid under other methodologies) APC Q4 Infectious agent detection by nucleic acid (DNA or RNA); influenza virus, for multiple types or sub-types, includes multiplex reverse transcription, when performed, and multiplex amplified probe technique, first 2 types or sub-types
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.
GW Service not related to the hospice patient's terminal condition
XU Unusual non-overlapping service, the use of a service that is distinct because it does not overlap usual components of the main service
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.
GV Attending physician not employed or paid under arrangement by the patient's hospice provider
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2016-01-01 Changed Description Changed
2015-01-01 Changed Description Changed
2013-01-01 Changed Medium Descriptor changed.
2011-01-01 Added Added
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