Coding Ahead
CasePilot
Medical Coding Assistant
Case2Code
Search and Code Lookup Tool
CareerCenter
Medical Coding Job Board
Log in Register free account

Need help choosing the right code?

Ask CasePilot about procedures, modifiers, bundling, and coding guidance.

Try CasePilot

Official Description

Antibody; Giardia lamblia

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

The CPT® Code 86674 refers to a laboratory test specifically designed to measure antibodies against Giardia lamblia, a microscopic parasite that is prevalent globally in various environments, including soil, food, and water. This parasite is primarily transmitted through fecal contamination from infected humans and animals. The presence of Giardia lamblia can lead to an intestinal infection, which is clinically characterized by symptoms such as abdominal cramps, bloating, diarrhea, and significant weight loss if the infection persists. The test measures different types of antibodies, including IgM, IgG, and IgA, which are crucial for diagnosing the infection. Elevated levels of IgM antibodies or a significant increase (four-fold rise) in IgG or IgA antibody titers between acute and convalescent serum samples indicate a recent or ongoing giardia infection. Conversely, a positive IgG or IgA antibody titer without detectable IgM antibodies typically suggests a past infection. To perform this test, a blood sample is collected through a procedure known as venipuncture, which is separately reportable. The serum obtained from the blood sample is then analyzed using a semi-quantitative enzyme-linked immunosorbent assay (ELISA) to detect the presence of these antibodies.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The antibody test for Giardia lamblia (CPT® Code 86674) is indicated for the following conditions:

  • Intestinal Infection The test is performed when a patient presents with symptoms indicative of a giardia infection, such as abdominal cramps, bloating, diarrhea, and weight loss.
  • Recent Infection Assessment It is utilized to determine if there is a recent or current giardia infection, particularly when elevated IgM antibodies or a significant rise in IgG/IgA titers is observed.
  • Past Infection Confirmation The test can also help confirm a past giardia infection when a positive IgG/IgA antibody titer is detected without measurable IgM antibodies.

2. Procedure

The procedure for testing antibodies against Giardia lamblia involves several key steps:

  • Step 1: Patient Preparation Prior to the test, the patient may be instructed to avoid certain medications or foods that could interfere with the results, although specific guidelines are not provided in the CPT® data.
  • Step 2: Venipuncture A blood sample is obtained through a procedure known as venipuncture. This involves the insertion of a needle into a vein, typically in the arm, to collect the necessary blood sample for testing. This step is crucial as it provides the serum needed for the antibody analysis.
  • Step 3: Serum Separation After blood collection, the sample is processed to separate the serum from the blood cells. This serum is what will be tested for the presence of antibodies.
  • Step 4: Antibody Testing The serum is then subjected to a semi-quantitative enzyme-linked immunosorbent assay (ELISA) to detect and measure the levels of IgG, IgA, and IgM antibodies specific to Giardia lamblia. This testing method allows for the determination of antibody presence and levels, which are critical for diagnosing current or past infections.

3. Post-Procedure

After the procedure, patients may experience minor discomfort or bruising at the venipuncture site, which typically resolves quickly. There are no specific post-procedure care instructions provided in the CPT® data. However, it is generally advisable for patients to hydrate adequately and monitor for any unusual symptoms. The results of the antibody test will be interpreted by a healthcare professional, who will consider the patient's clinical history and symptoms to determine the appropriate course of action based on the findings.

Short Descr GIARDIA LAMBLIA ANTIBODY
Medium Descr ANTIBODY GIARDIA LAMBLIA
Long Descr Antibody; Giardia lamblia
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 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.
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.
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.
Date
Action
Notes
2004-01-01 Changed Code description changed.
1993-01-01 Added First appearance in code book in 1993.
Code
Description
Code
Description
CasePilot

Get instant expert-level medical coding assistance.

Ask about:
CPT Codes Guidelines Modifiers Crosswalks NCCI Edits Compliance Medicare Coverage
Example: "What is CPT code 99213?" or "Guidelines for E/M services"