How To Use CPT Code 84166

CPT 84166 describes the process of protein electrophoretic fractionation and quantitation in fluids other than serum. This article will cover the official description, procedure, qualifying circumstances, appropriate usage, documentation requirements, billing guidelines, historical information, similar codes and billing examples.

1. What is CPT Code 84166?

CPT 84166 can be used to describe the technical lab test performed by a lab analyst to separate and evaluate the level of various protein fractions in fluids other than serum. This test, known as protein electrophoresis, involves using electrophoresis to migrate the protein fractions apart and measure their quantity in the specimen.

2. Official Description

The official description of CPT code 84166 is: ‘Protein; electrophoretic fractionation and quantitation, other fluids with concentration (eg, urine, CSF).’ This code specifically applies to the separation and measurement of protein fractions in fluids other than serum using electrophoresis.

3. Procedure

1. The lab analyst receives a specimen, such as urine or cerebrospinal fluid (CSF), for protein electrophoretic fractionation and quantitation.
2. The lab analyst performs electrophoresis, using a specialized instrument that applies an electrical field across a gel containing the specimen.
3. The electrical field causes the protein fractions in the specimen to migrate apart, allowing the instrument to record and calculate their quantity.
4. The lab analyst identifies and measures the level of protein fractions, such as albumin, alpha 1, alpha 2, beta globulin, and gamma globulin.
5. The lab analyst generates descriptive and quantitative results for the protein fractions in the specimen.

4. Qualifying circumstances

CPT 84166 is used when protein electrophoretic fractionation and quantitation are performed on fluids other than serum, such as urine or CSF. This test is often ordered by clinicians to evaluate conditions that result in elevated protein in body fluids. It can help identify elevated monoclonal antibody bands, which may indicate benign conditions like monoclonal gammopathies or blood cancers like multiple myeloma.

5. When to use CPT code 84166

CPT code 84166 should be used when performing protein electrophoretic fractionation and quantitation on fluids other than serum. It is appropriate to bill this code when the lab analyst separates and measures protein fractions in specimens like urine or CSF using electrophoresis.

6. Documentation requirements

To support a claim for CPT 84166, the lab analyst must document the following information:

• The type of specimen used for the test (e.g., urine, CSF)
• The date the test was performed
• The results of the protein electrophoretic fractionation and quantitation
• Any additional relevant information or observations

7. Billing guidelines

When billing for CPT 84166, ensure that the test is performed on fluids other than serum and that the results are generated through protein electrophoretic fractionation and quantitation. It is important to note that if the ordering clinician requests a written interpretation of the test results by a pathologist, the interpretation is a separate physician service that should be billed separately. The billing entity for the lab should report CPT 84166, while the billing entity for the pathologist should report the same code with modifier 26, indicating the professional component.

8. Historical information

CPT 84166 was added to the Current Procedural Terminology system on January 1, 2005. There have been no updates to the code since its addition.

9. Examples

1. A lab analyst performs protein electrophoretic fractionation and quantitation on a urine specimen to evaluate a patient with suspected kidney disease.
2. Protein electrophoretic fractionation and quantitation are performed on a CSF specimen to assess a patient with suspected central nervous system disorder.
3. A lab analyst separates and measures protein fractions in a pleural fluid specimen using electrophoresis to aid in the diagnosis of a patient with pleural effusion.
4. Protein electrophoretic fractionation and quantitation are performed on a synovial fluid specimen to evaluate a patient with suspected joint inflammation.
5. A lab analyst assesses the protein fractions in an amniotic fluid specimen using electrophoresis to aid in the diagnosis of a patient with suspected fetal abnormalities.
6. Protein electrophoretic fractionation and quantitation are performed on a peritoneal fluid specimen to evaluate a patient with suspected abdominal infection.
7. A lab analyst separates and measures protein fractions in a bronchoalveolar lavage fluid specimen using electrophoresis to aid in the diagnosis of a patient with suspected lung disease.
8. Protein electrophoretic fractionation and quantitation are performed on a gastric fluid specimen to evaluate a patient with suspected gastrointestinal disorder.
9. A lab analyst assesses the protein fractions in a synovial fluid specimen using electrophoresis to aid in the diagnosis of a patient with suspected joint disease.
10. Protein electrophoretic fractionation and quantitation are performed on a pericardial fluid specimen to evaluate a patient with suspected cardiac condition.