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Official Description

Infectious agent enzymatic activity other than virus (eg, sialidase activity in vaginal fluid)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 87905 refers to the testing of infectious agent enzymatic activity that is not associated with viral infections. This procedure typically involves the collection of a body fluid specimen, such as a vaginal swab, to assess the enzymatic activity of infectious agents. A specific example of this enzymatic activity is sialidase, an enzyme that plays a crucial role in the ability of certain microorganisms to invade and damage host tissues. Elevated levels of sialidase in vaginal fluid can indicate the presence of bacterial vaginosis, a common condition characterized by an imbalance of bacteria in the vagina. The testing process involves swabbing the lower third of the vaginal wall to collect an adequate sample of fluid, which is then placed in a capped tube for analysis. A chromogenic enzyme activity test is subsequently performed to detect sialidase activity. Additionally, CPT® Code 87905 can be utilized to report tests for other types of enzymatic activities related to infectious agents found in various body fluids, thereby broadening its application in clinical diagnostics.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The procedure associated with CPT® Code 87905 is indicated for the evaluation of infectious agent enzymatic activity in body fluids, particularly when there is a suspicion of bacterial vaginosis or other infections characterized by non-viral enzymatic activity. The following conditions may warrant this testing:

  • Bacterial Vaginosis Elevated sialidase activity in vaginal fluid may suggest the presence of bacterial vaginosis, a condition that can lead to various complications if left untreated.
  • Infection Assessment The test may be performed to assess other infections where enzymatic activity is a factor, aiding in the diagnosis and management of infectious diseases.

2. Procedure

The procedure for testing infectious agent enzymatic activity, specifically sialidase, involves several key steps to ensure accurate results. First, a healthcare professional obtains a vaginal swab from the lower third of the vaginal wall. This area is chosen to maximize the collection of vaginal fluid, which is essential for the test. The swab is rotated gently for a duration of 10 to 20 seconds to gather a sufficient amount of fluid onto the swab. Once the sample is collected, the swab is carefully placed into a sterile tube, which is then capped to prevent contamination. Following the collection, a chromogenic enzyme activity test is conducted on the sample to identify the presence of sialidase activity. This test utilizes specific reagents that react with the enzyme, allowing for the detection of elevated levels of sialidase, which can indicate an underlying infection.

3. Post-Procedure

After the procedure, there are generally no specific post-procedure care requirements for the patient, as the test is minimally invasive and does not typically cause discomfort. Patients may resume their normal activities immediately following the sample collection. However, it is important for healthcare providers to communicate the expected timeline for test results and any necessary follow-up actions based on the findings. If elevated sialidase activity is detected, further evaluation and treatment options may be discussed with the patient to address any underlying conditions.

Short Descr SIALIDASE ENZYME ASSAY
Medium Descr INFECTIOUS AGENT ENZYMATIC ACTV OTH/THN VIRUS
Long Descr Infectious agent enzymatic activity other than virus (eg, sialidase activity in vaginal fluid)
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 2
CCS Clinical Classification 206 - Microscopic examination (bacterial smear, culture, toxicology)
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.
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.
GC This service has been performed in part by a resident under the direction of a teaching physician
Date
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2009-01-01 Added -
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