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Code deleted, see 81200-81479

Official Description

Molecular diagnostics; amplification, target, multiplex, each additional nucleic acid sequence beyond 2 (List separately in addition to code for primary procedure)

© Copyright 2026 American Medical Association. All rights reserved.

Common Language Description

A molecular diagnostics test is a specialized laboratory procedure that utilizes target amplification techniques to replicate specific nucleic acid sequences, such as DNA or RNA. This process is essential for identifying particular genes and proteins, as well as understanding their interactions within cells. Molecular diagnostics focuses on analyzing patterns of gene and protein activity, which can reveal significant changes indicative of various diseases, including cancer, infections, and genetic disorders that may be inherited or acquired. The field of molecular diagnostics is rapidly evolving, with new applications emerging regularly, enhancing its role in modern medicine.

To perform this test, a biological sample—such as blood, urine, sputum, or tissue—is collected from the patient. The nucleic acid intended for amplification is then prepared and isolated through a separate, reportable procedure. Following this preparation, target amplification is conducted, which involves generating multiple copies of the specific nucleic acid sequence. This amplification process can be repeated, allowing for further replication of each copy. In cases where target amplification is necessary for more than one nucleic acid sequence, each sequence is reported separately. The initial two nucleic acid sequences are reported using CPT® code 83900, which employs multiplex technology to amplify multiple sequences simultaneously, potentially targeting 100 or more sequences at once. For each additional nucleic acid sequence beyond the first two, CPT® code 83901 is utilized, ensuring accurate reporting and billing for the comprehensive molecular diagnostic testing performed.

© Copyright 2026 Coding Ahead. All rights reserved.

1. Indications

The molecular diagnostics test using target amplification is indicated for a variety of clinical scenarios, particularly when there is a need to identify specific genetic material associated with diseases. The following conditions may warrant the use of this procedure:

  • Cancer Diagnosis Molecular diagnostics can help in identifying specific genetic mutations or alterations that are characteristic of certain types of cancer, aiding in diagnosis and treatment planning.
  • Infectious Diseases The test is useful for detecting the presence of pathogens, such as viruses or bacteria, by amplifying their nucleic acid sequences, which can confirm infections.
  • Hematological Disorders Conditions affecting blood cells, such as leukemias or lymphomas, can be evaluated through molecular diagnostics to identify genetic changes that may influence treatment options.
  • Neurological Disorders Genetic testing can assist in diagnosing inherited neurological conditions by identifying specific gene mutations.
  • Inherited Genetic Disorders The procedure is indicated for screening and diagnosing genetic disorders that are passed down through families, allowing for early intervention and management.

2. Procedure

The procedure for molecular diagnostics using target amplification involves several key steps, each critical to ensuring accurate results. The following outlines the procedural steps:

  • Step 1: Sample Collection A biological sample, such as blood, urine, sputum, or tissue, is collected from the patient. This sample serves as the source of nucleic acids for the test.
  • Step 2: Nucleic Acid Isolation The nucleic acid (DNA or RNA) is isolated from the collected sample. This step is crucial as it prepares the genetic material for amplification and is performed as a separate, reportable procedure.
  • Step 3: Target Amplification The isolated nucleic acid undergoes target amplification, where specific sequences are replicated to generate multiple copies. This amplification is essential for detecting low-abundance targets in the sample.
  • Step 4: Reporting Additional Sequences If the amplification involves more than two nucleic acid sequences, each additional sequence is reported separately using CPT® code 83901. The first two sequences are reported using CPT® code 83900.

3. Post-Procedure

After the molecular diagnostics procedure, the results are analyzed and interpreted by qualified laboratory personnel. The findings can provide critical information regarding the presence of specific genetic markers or pathogens. Depending on the results, further clinical action may be required, such as additional testing, treatment planning, or patient counseling. It is essential for healthcare providers to communicate the results effectively to patients and consider any necessary follow-up actions based on the diagnostic outcomes.

Short Descr MOLECULE NUCLEIC AMPLI ADDON
Medium Descr MOLECULE NUCLEIC AMPLI ADDON
Long Descr Molecular diagnostics; amplification, target, multiplex, each additional nucleic acid sequence 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
APC Status Indicator Discontinued Code
Type of Service (TOS) 5 - Diagnostic Laboratory
Berenson-Eggers TOS (BETOS) T1H - Lab tests - other (non-Medicare fee schedule)
MUE Not applicable/unspecified.
CCS Clinical Classification 233 - Laboratory - Chemistry and Hematology
Date
Action
Notes
2013-01-01 Deleted Code deleted, see 81200-81479
2013-01-01 Changed Short and Medium Descriptors changed.
2008-01-01 Changed Code description changed.
2006-01-01 Changed Code description changed.
1999-01-01 Added Code added
Code
Description
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