A urinalysis is a common laboratory test that provides information about a patient’s overall health by analyzing a urine sample. The procedure is divided into a chemical analysis, which uses reagent strips (dipstick) to detect various substances, and a microscopic analysis. The microscopic examination involves centrifuging the sample to concentrate the sediment, which is then viewed under a microscope. This allows for the identification and quantification of formed elements such as red blood cells (RBCs), white blood cells (WBCs), epithelial cells, urinary casts, and crystals. Analyzing these elements helps diagnose conditions like kidney disease, urinary tract infections, and diabetes.
Reporting Microscopic Examination Only
The specific Current Procedural Terminology (CPT) code for a microscopic examination performed in isolation is 81015, described as “Urinalysis; microscopic only.” This code is used when a provider orders an examination of the urine sediment without the accompanying chemical analysis. This often occurs in a “reflex” testing protocol.
In a reflex protocol, an automated chemical urinalysis is performed first. If the results are abnormal—such as positive readings for protein, blood, or leukocyte esterase—the laboratory proceeds to the microscopic analysis. Since the initial chemical screen is coded separately, the lab reports the subsequent microscopic work using CPT 81015. This method conserves resources by avoiding unnecessary manual review for normal samples.
Code Selection for Complete Urinalysis
The majority of urinalysis procedures are “complete” tests, combining both chemical and microscopic components into a single service. The complete urinalysis is represented by CPT codes 81000 or 81001. The choice depends on the methodology used for the chemical component.
CPT 81000 is used for a non-automated complete urinalysis, where the chemical analysis (dipstick) is read visually, followed by the microscopic examination. CPT 81001 is used for an automated complete urinalysis, where an instrument reads the reagent strip, followed by the microscopic examination. These codes are comprehensive and are the most common codes reported for full urinalysis testing. If a complete urinalysis is performed, it is inappropriate to bill 81000 or 81001 alongside the microscopic-only code, 81015.
Rules for Unbundling and Modifier Use
The Centers for Medicare & Medicaid Services (CMS) and private payers enforce billing regulations through the National Correct Coding Initiative (NCCI) Program. NCCI edits prevent the separate billing of services that are components of a more comprehensive procedure. The microscopic urinalysis (81015) is bundled with the chemical urinalysis codes (81002/81003) because the microscopic exam often follows the chemical screen.
Billing the microscopic-only code (81015) and a chemical-only code (81002 or 81003) together for the same sample on the same date of service will result in a claim denial. Separate billing, or “unbundling,” is only permissible when the services are distinctly separate and meet specific criteria.
To bypass an NCCI edit, a provider may append Modifier 59, signifying a “Distinct Procedural Service.” This modifier is appropriate only when the two tests are performed on different specimens, at different encounters, or represent truly independent clinical procedures. For example, if a chemical urinalysis is performed for specimen validity during a drug screen, and a separate microscopic urinalysis is ordered later that day for a suspected urinary tract infection, Modifier 59 may be warranted. If the microscopic exam is performed solely because the initial chemical dipstick was abnormal, it is considered a single, bundled service, and Modifier 59 should not be used.
Supporting Medical Necessity with Documentation
Accurate coding depends on detailed clinical documentation that establishes the medical necessity for the services rendered. The patient’s medical record must contain a clear physician order that specifically requests the test. Documentation must also include the clinical reason for the test, conveyed through appropriate ICD-10 diagnosis codes.
These diagnosis codes should reflect signs or symptoms of a urinary tract disorder or a condition affecting the kidneys, such as hematuria, flank pain, or diabetes mellitus. The laboratory’s actual results of the microscopic examination—detailing the presence and quantity of cells, casts, or crystals—must also be recorded. This evidence confirms the test was necessary for the patient’s diagnostic workup or treatment monitoring, justifying the CPT code reported.