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83884 Assay neurflmnt light chain

What 83884 is

CMS fee schedule short descriptor: Assay neurflmnt light chain.

Full CPT long descriptions are licensed by the American Medical Association and are not published on this site; the short descriptor above is the one CMS prints in its own fee schedule file. See About CPT.

Medicare payment for 83884 (CY2026)

This code has no Physician Fee Schedule rate: Statutory exclusion - not payable under the Physician Fee Schedule. It may be paid under a different fee schedule (clinical laboratory, DMEPOS, anesthesia) or not paid at all - check the relevant CMS schedule.

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Medically Unlikely Edit (MUE)

Medicare caps 83884 at 1 unit per date of service for practitioner claims (MAI 2 - date of service edit (absolute): units above the MUE never pay), rationale: Code Descriptor / CPT Instruction. Units above the cap are denied unless the edit's adjudication rules allow an appeal with documentation.

Billed with 83884? These codes are bundled into it

83884 is a Column 1 code in 7 active NCCI PTP edits. When one of these Column 2 codes is reported on the same date of service, it is denied as bundled - unless the edit's modifier indicator is 1 and documentation supports a distinct service with an NCCI-associated modifier.

Column 2 codeShort descriptionModifier indicator
36591Draw blood off venous device0 - no modifier bypassCheck pair
36592Collect blood from picc0 - no modifier bypassCheck pair
80503Path clin consltj sf 5-201 - modifier may bypassCheck pair
80504Path clin consltj mod 21-401 - modifier may bypassCheck pair
80505Path clin consltj high 41-601 - modifier may bypassCheck pair
81406Mopath procedure level 71 - modifier may bypassCheck pair
96523Irrig drug delivery device0 - no modifier bypassCheck pair

83884 is bundled into these codes

83884 appears as a Column 2 code in 13 active edits. Reported with one of these Column 1 codes on the same date of service, 83884 is the code that denies.

Column 1 codeShort descriptionModifier indicator
0035U1Check pair
0077U1Check pair
0289U1Check pair
0358U1Check pair
0393U1Check pair
0443U0Check pair
0445U1Check pair
0503U1Check pair
81284Fxn gene detc abnor alleles1Check pair
81285Fxn gene charac alleles1Check pair
81286Fxn gene full gene sequence1Check pair
81289Fxn gene known famil variant1Check pair
84166Protein e-phoresis/urine/csf1Check pair

Data: CMS CY2026 Physician Fee Schedule RVU file (October release, RVU26D) and Medicare NCCI PTP practitioner edits v32.3 (2026 Q4). Verify against the official files before billing or contracting decisions.