CPT code 88319: Enzyme histochemistry, each specimen2026 Medicare rate & RVUs

Reports enzyme histochemical analysis of a tissue specimen, often in muscle biopsy workups where demonstrating enzyme activity helps characterize a disorder.

CMS RVU26DEffective Oct 1, 2026109 payment localities12.4K Medicare services in 2024

Medicare pays $131.93 for 88319 nationally in the office. Local office rates run $115.44–$183.57.

Medicare rate · 88319

Enzyme histochemistry, each specimen

Office or facility?

Work RVUs
0.52
Total RVUs
3.95
Global days
XXX

National rate · 2026

$131.93

Office setting, before claim adjustments.

See every locality for 88319 →Billed by an NP, PA or therapist? →

Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.

Your location

Medicare pays by the payment locality where the service is performed.

On this page 10 sections
  1. Medicare rate
  2. What 88319 covers
  3. By payment locality
  4. Rate map
  5. How it’s calculated
  6. Payment rules
  7. Similar codes
  8. Related codes
  9. Billing questions
  10. Sources

What 88319 covers

Enzyme histochemistry uses stains to demonstrate enzyme activity in tissue, supporting evaluation of suspected metabolic or neuromuscular disease. A common setting is a muscle biopsy workup, where a pathology laboratory processes tissue and a pathologist interprets the staining pattern. The service is reported for each specimen analyzed, rather than for each individual stain applied to that specimen.

Select the code when the documented work specifically evaluates tissue enzyme activity. The pathology report and laboratory record should identify the specimen and findings that support the enzyme study. Medicare recognizes professional and technical components: modifier 26 identifies the interpretation, modifier TC identifies the laboratory work, and billing without either modifier represents the global service.

This summary was written with AI assistance from CMS physician fee schedule data and checked against the CMS billing rules shown here. Rates on this page come directly from CMS files.

Where 88319 pays more and less

The same RVUs, adjusted for each area’s costs. Open a locality for its calculation, history and nearby areas.

109 payment localities

$115.44 to $183.57

$115.44$149.50$183.57
One dot per payment locality, office / nonfacility. Hover a dot to see the locality; select it to open that rate.

109 of 109 payment localities

88319 office and facility rates by payment locality
Payment localityOfficeFacility
Alabama$117.30Unavailable
Alaska$147.55Unavailable
Arizona$128.27Unavailable
Arkansas$115.44Unavailable
Atlanta, GA$134.00Unavailable
Austin, TX$138.44Unavailable
Bakersfield, CA$142.77Unavailable
Baltimore area, MD$140.74Unavailable
Beaumont, TX$121.64Unavailable
Brazoria, TX$130.83Unavailable

88319 rates by state

Office rate range in each state. Select a state to see its payment localities.

Explore a state

Local rates. Clear comparisons.

Hover or focus a tile to see its rate range. Select it to open the state’s fee schedule.

$115.44

$163.12

Color shows the midpoint of each state’s locality range.

View every state and territory as a table
88319 office rate range by state
State / territoryOffice rate rangeLocalities
AK$147.551
AL$117.301
AR$115.441
AZ$128.271
CA$142.67–$183.5729
CO$139.191
CT$141.241
DC$153.201
DE$130.561
FL$127.44–$138.123
GA$119.86–$134.002
GU$147.071
HI$147.071
IA$121.681
ID$122.321
IL$122.62–$135.894
IN$123.131
KS$120.531
KY$119.241
LA$118.83–$125.372
MA$138.03–$154.572
MD$133.39–$153.203
ME$122.47–$130.542
MI$122.18–$128.652
MN$134.521
MO$116.24–$126.483
MS$115.891
MT$131.931
NC$123.961
ND$131.341
NE$122.571
NH$136.461
NJ$143.17–$151.272
NM$122.711
NV$131.881
NY$125.96–$155.375
OH$122.061
OK$119.561
OR$131.18–$144.562
PA$122.57–$137.102
PR$133.171
RI$135.901
SC$123.151
SD$131.271
TN$121.141
TX$121.64–$138.448
UT$125.021
VA$129.71–$153.202
VI$133.171
VT$130.301
WA$137.94–$158.402
WI$126.471
WV$117.491
WY$131.671

How the 88319 rate is calculated

Each of 88319’s three RVUs is multiplied by a geographic index (GPCI) for the payment locality, added up, and multiplied by the conversion factor. Drag the indexes or enter a ZIP to see what moves the rate.

How the rate is built · 88319

RVUs × geographic indexes × conversion factor

Office or facility?

Work0.52

0.52 RVUs× 1.000 GPCI

Practice expense3.40

3.40 RVUs× 1.000 GPCI

Malpractice0.03

0.03 RVUs× 1.000 GPCI

Adjusted RVUs

3.9500

Conversion factor

$33.4009

Medicare rate

$131.93

Every GPCI starts at 1.000, the national rate. Enter a ZIP or drag a slider.

Payment rules and modifiers for 88319

The CMS indicators that decide how 88319 is paid alongside other services.

CMS payment indicators · 88319

Enzyme histochemistry, each specimen

RuleCMS valueWhat it means
Global periodXXXThe global surgery concept doesn’t apply.
Multiple procedures0No multiple-procedure reduction.
Bilateral (modifier 50)0The 150% bilateral adjustment doesn’t apply.
Assistant at surgery (80/81/82/AS)0Not paid without supporting documentation.
Co-surgeons (62)0Not permitted.
Team surgery (66)0Not permitted.
Professional/technical1Diagnostic test with separate professional (26) and technical (TC) components.

What modifiers do to the payment

Modifier 26 · payment effect

With and without the modifier

88319 without 26 · national office

$131.93

Enzyme histochemistry, each specimen

88319-26 · Professional component

$25.38

Pays only the interpretation and report.

When to use modifier 26

88319 compared with similar codes

Compare codes · National

5 codes, side by side

Office or facility?

  • 88319

    Enzyme histochemistry, each specimen0.52 wRVU

    $131.93

  • 88312

    Special stain, group I, microorganisms0.53 wRVU

    $109.55−$22.38

  • 88313

    Special stain, group II, tissue constituents0.23 wRVU

    $80.83−$51.10

  • 88314

    Histochemical stain, group III stain0.44 wRVU

    $81.83−$50.10

  • 88342

    Antibody stain, first single antibody per specimen0.68 wRVU

    $110.22−$21.71

How to choose

88312Special stainGroup I, microorganisms
88312 represents its designated special-stain group, including stains used to identify microorganisms. Use 88319 when the study demonstrates enzyme activity in tissue.
88313Special stainGroup II, tissue constituents
88313 covers a different designated special-stain group. The distinction is the stain type and purpose, not simply the number of stains performed.
88314Histochemical stainGroup III stain
88314 is for histochemical staining on frozen sections. Code 88319 is selected for enzyme histochemistry by specimen.
88342Antibody stainFirst single antibody per specimen
88342 reports immunohistochemistry using an antibody. Choose 88319 when the tissue study demonstrates enzyme activity instead.

88319 billing questions

Is 88319 reported per stain or per specimen?

Report it per specimen analyzed. Multiple enzyme stains on the same specimen do not, by themselves, establish multiple units.

When should 88319 be chosen over 88312 or 88313?

Use 88319 for tissue enzyme histochemistry. Codes 88312 and 88313 cover other special-stain groups, so choose according to the type of stain performed.

How are the professional and technical services reported?

Use modifier 26 for the pathologist’s interpretation and modifier TC for the laboratory work. Without either modifier, the claim represents the global service.

What documentation supports reporting 88319?

The record should identify the tissue specimen and document enzyme histochemical analysis and the resulting interpretation. A general tissue examination alone does not establish this service.

Can 88319 be reported with a surgical pathology examination?

It may be reported with a surgical pathology examination when enzyme histochemistry is separately performed and documented for the specimen. The pathology record should support both services.

Where these rates come from

FeeBase calculates base physician payments from CMS work, practice-expense and malpractice RVUs, adjusted by each locality’s geographic indexes and the conversion factor. Services without a published rate are labeled, never given a made-up amount. Amounts are Medicare allowed amounts before claim adjustments: not a patient’s bill or a commercial rate.

CMS RVU26D · effective Oct 1, 2026 through the day before Jan 1, 2027

Show the CMS file lines behind this rate
RVUs for 88319PPRRVU2026_Oct_nonQPP.csv, line 11,227 (RVU26D)

Open CMS sourceHow we calculate rates

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