Summary & Overview
CPT 83625: Lactate Dehydrogenase (LDH) Isoenzyme Fractionation
CPT code 83625 denotes laboratory measurement of lactate dehydrogenase (LDH) isoenzymes, typically performed on a serum specimen to fractionate LDH into its component isoenzymes. This test helps clinicians localize tissue injury or hemolysis when overall LDH is elevated and is used across inpatient and outpatient laboratory settings nationwide. The code is clinically important for differential diagnosis in hepatic, cardiac, renal, and hematologic conditions and affects utilization and reimbursement patterns for clinical laboratories.
Key payers covered in this analysis include Aetna, Blue Cross Blue Shield, Cigna Health, UnitedHealthcare, and Medicare. Readers will find a concise overview of CPT code 83625, clinical context for when LDH isoenzyme testing is ordered, and what service settings typically bill this code. The publication summarizes benchmarking and payment considerations where available, notes common billing modifiers, and highlights areas where policy updates or coding guidance can affect coverage and claims processing. Practical items covered include typical site-of-service considerations, how the code fits into laboratory service lines, and national-level implications for utilization and laboratory workflow.
Data not available in the input for some items such as associated taxonomies, specific ICD-10 pairings, payer-specific rates, and related codes.
Billing Code Overview
CPT code 83625 reports measurement of lactate dehydrogenase (LDH) isoenzymes in a serum sample. The test separates LDH into its constituent isoenzymes to help characterize tissue sources of LDH elevation, including liver, kidney, heart, and red blood cells.
Service type: Clinical laboratory diagnostic test
Typical site of service: Clinical laboratory or hospital laboratory (serum specimen)
Clinical & Coding Specifications
Clinical Context
A 62-year-old male presents to the hospital emergency department with chest pain and shortness of breath. The emergency clinician orders a battery of serum chemistry and enzyme tests, including measurement of lactate dehydrogenase (LDH) isoenzymes, to help assess for myocardial injury, hemolysis, or hepatic injury when initial troponin and liver panel results are equivocal or when a historical presentation suggests subacute tissue injury. A phlebotomist draws a serum sample which is sent to the hospital clinical laboratory. A medical laboratory technologist performs fractionation of LDH to identify isoenzyme patterns (LDH-1 through LDH-5) using electrophoresis or other validated analytic methods. The laboratory documents results in the electronic medical record; the pathologist or laboratory director reviews and signs the report when required. Results are used by the treating team to correlate with clinical findings and other biomarkers to guide further diagnostic workup or management decisions.
Coding Specifications
| Modifier | Description | When to Use |
|---|---|---|
26 | Professional component | Use when billing only the professional (interpretation) component separate from the technical component. |
TC | Technical component |