CPT code 88319: Enzyme histochemistry, each specimen2026 Medicare rate & RVUs in Connecticut
Reports enzyme histochemical analysis of a tissue specimen, often in muscle biopsy workups where demonstrating enzyme activity helps characterize a disorder.
In Connecticut, Medicare pays $141.24 for 88319 in the office.
Check a contract rate as a % of Medicare · 88319 nationwide
Medicare allowed amount for participating (non-QP) physicians, before deductible, coinsurance and claim adjustments. Not a patient’s bill or a hospital charge.
On this page 11 sections
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.
How Connecticut compares for 88319
Across 109 of 109 payment localities, the office rate for 88319 runs from $115.44 in Arkansas to $183.57 in San Benito County, CA. Connecticut pays $141.24. The RVUs are the same everywhere; the geographic indexes change the dollars.
- Connecticut · this page$141.24
- Los Angeles, CA · California$153.09+$11.85
- Washington, DC area · District of Columbia$153.20+$11.96
- Miami, FL · Florida$138.12−$3.12
- Chicago, IL · Illinois$133.92−$7.32
- Manhattan, NY · New York$152.03+$10.79
- Alaska · Alaska$147.55+$6.31
Other areas in Connecticut first, then benchmark localities. Bars start at $0.
Every other payment area
| Payment locality | Office | Facility |
|---|---|---|
| AlabamaAlabama | $117.30 | — |
| ArkansasArkansas | $115.44 | — |
| ArizonaArizona | $128.27 | — |
| Bakersfield, CACalifornia | $142.77 | — |
| Chico, CACalifornia | $142.67 | — |
| El Centro, CACalifornia | $142.67 | — |
| Fresno, CACalifornia | $142.67 | — |
| Hanford, CACalifornia | $142.67 | — |
| Madera, CACalifornia | $142.67 | — |
| Merced, CACalifornia | $142.67 | — |
| Modesto, CACalifornia | $142.67 | — |
| Napa, CACalifornia | $168.65 | — |
| Oxnard, CACalifornia | $152.71 | — |
| Redding, CACalifornia | $142.67 | — |
| Rest of CaliforniaCalifornia | $142.67 | — |
| Riverside, CACalifornia | $143.00 | — |
| Sacramento, CACalifornia | $150.60 | — |
| Salinas, CACalifornia | $150.06 | — |
| San Diego, CACalifornia | $154.25 | — |
| Marin County, CACalifornia | $179.60 | — |
| San Francisco, CACalifornia | $179.57 | — |
| San Benito County, CACalifornia | $183.57 | — |
| Santa Clara County, CACalifornia | $183.43 | — |
| San Luis Obispo, CACalifornia | $147.55 | — |
| Santa Cruz, CACalifornia | $156.25 | — |
| Santa Maria, CACalifornia | $150.81 | — |
| Santa Rosa, CACalifornia | $157.88 | — |
| Stockton, CACalifornia | $142.67 | — |
| Vallejo, CACalifornia | $168.60 | — |
| Visalia, CACalifornia | $142.67 | — |
| Yuba City, CACalifornia | $142.67 | — |
| ColoradoColorado | $139.19 | — |
| DelawareDelaware | $130.56 | — |
| Fort Lauderdale, FLFlorida | $134.22 | — |
| Rest of FloridaFlorida | $127.44 | — |
| Atlanta, GAGeorgia | $134.00 | — |
| Rest of GeorgiaGeorgia | $119.86 | — |
| Hawaii, Guam, HIHawaii | $147.07 | — |
| IowaIowa | $121.68 | — |
| IdahoIdaho | $122.32 | — |
| East St. Louis, ILIllinois | $123.86 | — |
| Rest of IllinoisIllinois | $122.62 | — |
| Suburban Chicago, ILIllinois | $135.89 | — |
| IndianaIndiana | $123.13 | — |
| KansasKansas | $120.53 | — |
| KentuckyKentucky | $119.24 | — |
| New Orleans, LALouisiana | $125.37 | — |
| Rest of LouisianaLouisiana | $118.83 | — |
| Metropolitan Boston, MAMassachusetts | $154.57 | — |
| Rest of MassachusettsMassachusetts | $138.03 | — |
| Baltimore area, MDMaryland | $140.74 | — |
| Rest of MarylandMaryland | $133.39 | — |
| Rest of MaineMaine | $122.47 | — |
| Southern Maine, MEMaine | $130.54 | — |
| Detroit, MIMichigan | $128.65 | — |
| Rest of MichiganMichigan | $122.18 | — |
| MinnesotaMinnesota | $134.52 | — |
| Metropolitan Kansas City, MOMissouri | $124.98 | — |
| Metropolitan St. Louis, MOMissouri | $126.48 | — |
| Rest of MissouriMissouri | $116.24 | — |
| MississippiMississippi | $115.89 | — |
| MontanaMontana | $131.93 | — |
| North CarolinaNorth Carolina | $123.96 | — |
| North DakotaNorth Dakota | $131.34 | — |
| NebraskaNebraska | $122.57 | — |
| New HampshireNew Hampshire | $136.46 | — |
| Northern New JerseyNew Jersey | $151.27 | — |
| Rest of New JerseyNew Jersey | $143.17 | — |
| New MexicoNew Mexico | $122.71 | — |
| NevadaNevada | $131.88 | — |
| NYC suburbs and Long Island, NYNew York | $155.37 | — |
| Poughkeepsie and northern NYC suburbs, NYNew York | $143.71 | — |
| Queens, NYNew York | $154.16 | — |
| Rest of New YorkNew York | $125.96 | — |
| OhioOhio | $122.06 | — |
| OklahomaOklahoma | $119.56 | — |
| Portland, OROregon | $144.56 | — |
| Rest of OregonOregon | $131.18 | — |
| Metropolitan Philadelphia, PAPennsylvania | $137.10 | — |
| Rest of PennsylvaniaPennsylvania | $122.57 | — |
| Puerto RicoPuerto Rico | $133.17 | — |
| Rhode IslandRhode Island | $135.90 | — |
| South CarolinaSouth Carolina | $123.15 | — |
| South DakotaSouth Dakota | $131.27 | — |
| TennesseeTennessee | $121.14 | — |
| Austin, TXTexas | $138.44 | — |
| Beaumont, TXTexas | $121.64 | — |
| Brazoria, TXTexas | $130.83 | — |
| Dallas, TXTexas | $131.49 | — |
| Fort Worth, TXTexas | $130.37 | — |
| Galveston, TXTexas | $131.11 | — |
| Houston, TXTexas | $131.65 | — |
| Rest of TexasTexas | $126.04 | — |
| UtahUtah | $125.02 | — |
| VirginiaVirginia | $129.71 | — |
| Virgin Islands, VIUnited States Virgin Islands | $133.17 | — |
| VermontVermont | $130.30 | — |
| Rest of WashingtonWashington | $137.94 | — |
| King County, WAWashington | $158.40 | — |
| WisconsinWisconsin | $126.47 | — |
| West VirginiaWest Virginia | $117.49 | — |
| WyomingWyoming | $131.67 | — |
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
| State / territory | Office rate range | Localities |
|---|---|---|
| AK | $147.55 | 1 |
| AL | $117.30 | 1 |
| AR | $115.44 | 1 |
| AZ | $128.27 | 1 |
| CA | $142.67–$183.57 | 29 |
| CO | $139.19 | 1 |
| CT | $141.24 | 1 |
| DC | $153.20 | 1 |
| DE | $130.56 | 1 |
| FL | $127.44–$138.12 | 3 |
| GA | $119.86–$134.00 | 2 |
| GU | $147.07 | 1 |
| HI | $147.07 | 1 |
| IA | $121.68 | 1 |
| ID | $122.32 | 1 |
| IL | $122.62–$135.89 | 4 |
| IN | $123.13 | 1 |
| KS | $120.53 | 1 |
| KY | $119.24 | 1 |
| LA | $118.83–$125.37 | 2 |
| MA | $138.03–$154.57 | 2 |
| MD | $133.39–$153.20 | 3 |
| ME | $122.47–$130.54 | 2 |
| MI | $122.18–$128.65 | 2 |
| MN | $134.52 | 1 |
| MO | $116.24–$126.48 | 3 |
| MS | $115.89 | 1 |
| MT | $131.93 | 1 |
| NC | $123.96 | 1 |
| ND | $131.34 | 1 |
| NE | $122.57 | 1 |
| NH | $136.46 | 1 |
| NJ | $143.17–$151.27 | 2 |
| NM | $122.71 | 1 |
| NV | $131.88 | 1 |
| NY | $125.96–$155.37 | 5 |
| OH | $122.06 | 1 |
| OK | $119.56 | 1 |
| OR | $131.18–$144.56 | 2 |
| PA | $122.57–$137.10 | 2 |
| PR | $133.17 | 1 |
| RI | $135.90 | 1 |
| SC | $123.15 | 1 |
| SD | $131.27 | 1 |
| TN | $121.14 | 1 |
| TX | $121.64–$138.44 | 8 |
| UT | $125.02 | 1 |
| VA | $129.71–$153.20 | 2 |
| VI | $133.17 | 1 |
| VT | $130.30 | 1 |
| WA | $137.94–$158.40 | 2 |
| WI | $126.47 | 1 |
| WV | $117.49 | 1 |
| WY | $131.67 | 1 |
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
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.
The exact Connecticut inputs and CMS source lines
PPRRVU2026_Oct_nonQPP.csv
11,227
- Code
- 88319
- Physician work
- 0.52
- Practice expense
- 3.40
- Malpractice
- 0.03
GPCI2026.csv
38
- Locality
- Connecticut
- Physician work
- 1.020
- Practice expense
- 1.077
- Malpractice
- 1.210
| Component | RVU | Locality factor | Adjusted |
|---|---|---|---|
| Physician work | 0.52 | × 1.020 | 0.5304 |
| Practice expense | 3.40 | × 1.077 | 3.6618 |
| Malpractice | 0.03 | × 1.210 | 0.0363 |
| Total RVUs | 4.2285 | ||
| Conversion factor | × 33.4009 | ||
Office rate, Connecticut$141.24
Office: (0.52 × 1.02 + 3.4 × 1.077 + 0.03 × 1.21) × $33.4009 = $141.24
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
| Rule | CMS value | What it means |
|---|---|---|
| Global period | XXX | The global surgery concept doesn’t apply. |
| Multiple procedures | 0 | No multiple-procedure reduction. |
| Bilateral (modifier 50) | 0 | The 150% bilateral adjustment doesn’t apply. |
| Assistant at surgery (80/81/82/AS) | 0 | Not paid without supporting documentation. |
| Co-surgeons (62) | 0 | Not permitted. |
| Team surgery (66) | 0 | Not permitted. |
| Professional/technical | 1 | Diagnostic 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.
How 88319 has changed in Connecticut
88319 · Office / nonfacility
$141.24
Effective 2026-10-01
The base rate is $0.97 lower than on 2025-10-01, moving from $142.21 to $141.24 (0.7%).
It is unchanged from the immediately preceding available release, effective 2026-07-01.
One bar per available release, ordered by effective date. Missing rates remain gaps. These comparisons hold the code, setting and locality identifiers constant; they do not isolate which policy or input caused a change.
What changed, release by release
January 1, 2026
RVU26A
$142.21changed to$141.24
- Conversion factor 32.3465 changed to 33.4009
- Work RVU 0.53 changed to 0.52
- Practice expense RVU 3.50 changed to 3.40
- Work GPCI 1.022 changed to 1.020
- Practice expense GPCI 1.091 changed to 1.077
- Malpractice GPCI 1.207 changed to 1.210
Held through RVU26B, RVU26C, RVU26D.
January 1, 2025
RVU25A
$147.80changed to$142.21
- Conversion factor 33.2875 changed to 32.3465
- Practice expense RVU 3.54 changed to 3.50
Held through RVU25B, RVU25C, RVU25D.
March 9, 2024
RVU24AR
$145.38changed to$147.80
- Conversion factor 32.7442 changed to 33.2875
Held through RVU24B, RVU24C, RVU24D.
January 1, 2024
RVU24A
$149.54changed to$145.38
- Conversion factor 33.8872 changed to 32.7442
- Practice expense RVU 3.48 changed to 3.54
- Work GPCI 1.030 changed to 1.022
- Practice expense GPCI 1.102 changed to 1.091
- Malpractice GPCI 1.070 changed to 1.207
January 1, 2023
RVU23A
$156.85changed to$149.54
- Conversion factor 34.6062 changed to 33.8872
- Practice expense RVU 3.55 changed to 3.48
- Work GPCI 1.037 changed to 1.030
- Practice expense GPCI 1.114 changed to 1.102
- Malpractice GPCI 0.934 changed to 1.070
Held through RVU23B, RVU23C, RVU23D.
January 1, 2022
RVU22A
$143.38changed to$156.85
- Conversion factor 34.8931 changed to 34.6062
- Practice expense RVU 3.17 changed to 3.55
Held through RVU22B, RVU22C, RVU22D.
January 1, 2021
RVU21A
$124.91changed to$143.38
- Conversion factor 36.0896 changed to 34.8931
- Practice expense RVU 2.60 changed to 3.17
- Malpractice RVU 0.02 changed to 0.03
- Work GPCI 1.029 changed to 1.037
- Practice expense GPCI 1.113 changed to 1.114
- Malpractice GPCI 1.094 changed to 0.934
Held through RVU21B, RVU21C, RVU21D.
January 1, 2020
RVU20A
$108.17changed to$124.91
- Conversion factor 36.0391 changed to 36.0896
- Practice expense RVU 2.19 changed to 2.60
- Work GPCI 1.021 changed to 1.029
- Practice expense GPCI 1.112 changed to 1.113
- Malpractice GPCI 1.255 changed to 1.094
Held through RVU20B, RVU20C, RVU20D.
January 1, 2019
RVU19A
$98.45changed to$108.17
- Conversion factor 35.9996 changed to 36.0391
- Practice expense RVU 1.95 changed to 2.19
Held through RVU19B, RVU19C, RVU19D.
January 1, 2018
RVU18AR1
$98.92changed to$98.45
- Conversion factor 35.8887 changed to 35.9996
- Practice expense RVU 1.96 changed to 1.95
- Work GPCI 1.023 changed to 1.021
- Practice expense GPCI 1.117 changed to 1.112
- Malpractice GPCI 1.244 changed to 1.255
Held through RVU18B, RVU18C, RVU18D.
January 1, 2017
RVU17A
$98.98changed to$98.92
- Conversion factor 35.8043 changed to 35.8887
- Work GPCI 1.024 changed to 1.023
- Practice expense GPCI 1.121 changed to 1.117
- Malpractice GPCI 1.232 changed to 1.244
Held through RVU17B, RVU17C, RVU17D.
January 1, 2016
RVU16A
$98.17changed to$98.98
- Conversion factor 35.9335 changed to 35.8043
- Practice expense RVU 1.92 changed to 1.96
- Malpractice RVU 0.03 changed to 0.02
Held through RVU16B, RVU16C, RVU16D.
July 1, 2015
RVU15C
$97.68changed to$98.17
- Conversion factor 35.7547 changed to 35.9335
Held through RVU15D.
January 1, 2015
RVU15A
$94.37changed to$97.68
- Conversion factor 35.8228 changed to 35.7547
- Practice expense RVU 1.83 changed to 1.92
- Malpractice RVU 0.04 changed to 0.03
- Practice expense GPCI 1.116 changed to 1.121
- Malpractice GPCI 1.234 changed to 1.232
Held through RVU15B.
January 1, 2014
RVU14A
$95.68changed to$94.37
- Conversion factor 34.0230 changed to 35.8228
- Practice expense RVU 2.00 changed to 1.83
- Practice expense GPCI 1.110 changed to 1.116
- Malpractice GPCI 1.235 changed to 1.234
Held through RVU14B, RVU14C, RVU14D.
January 1, 2013
RVU13AR
Earliest loaded release: $95.68
Held through RVU13B, RVU13C, RVU13D.
| Effective from | Office | Facility | CMS release |
|---|---|---|---|
| 2026-10-01 | $141.24 | Not available in this setting | RVU26D |
| 2026-07-01 | $141.24 | Not available in this setting | RVU26C |
| 2026-04-01 | $141.24 | Not available in this setting | RVU26B |
| 2026-01-01 | $141.24 | Not available in this setting | RVU26A |
| 2025-10-01 | $142.21 | Not available in this setting | RVU25D |
| 2025-07-01 | $142.21 | Not available in this setting | RVU25C |
| 2025-04-01 | $142.21 | Not available in this setting | RVU25B |
| 2025-01-01 | $142.21 | Not available in this setting | RVU25A |
| 2024-10-01 | $147.80 | Not available in this setting | RVU24D |
| 2024-07-01 | $147.80 | Not available in this setting | RVU24C |
| 2024-04-01 | $147.80 | Not available in this setting | RVU24B |
| 2024-03-09 | $147.80 | Not available in this setting | RVU24AR |
| 2024-01-01 | $145.38 | Not available in this setting | RVU24A |
| 2023-10-01 | $149.54 | Not available in this setting | RVU23D |
| 2023-07-01 | $149.54 | Not available in this setting | RVU23C |
| 2023-04-01 | $149.54 | Not available in this setting | RVU23B |
| 2023-01-01 | $149.54 | Not available in this setting | RVU23A |
| 2022-10-01 | $156.85 | Not available in this setting | RVU22D |
| 2022-07-01 | $156.85 | Not available in this setting | RVU22C |
| 2022-04-01 | $156.85 | Not available in this setting | RVU22B |
| 2022-01-01 | $156.85 | Not available in this setting | RVU22A |
| 2021-10-01 | $143.38 | Not available in this setting | RVU21D |
| 2021-07-01 | $143.38 | Not available in this setting | RVU21C |
| 2021-04-01 | $143.38 | Not available in this setting | RVU21B |
| 2021-01-01 | $143.38 | Not available in this setting | RVU21A |
| 2020-10-01 | $124.91 | Not available in this setting | RVU20D |
| 2020-07-01 | $124.91 | Not available in this setting | RVU20C |
| 2020-04-01 | $124.91 | Not available in this setting | RVU20B |
| 2020-01-01 | $124.91 | Not available in this setting | RVU20A |
| 2019-10-01 | $108.17 | Not available in this setting | RVU19D |
| 2019-07-01 | $108.17 | Not available in this setting | RVU19C |
| 2019-04-01 | $108.17 | Not available in this setting | RVU19B |
| 2019-01-01 | $108.17 | Not available in this setting | RVU19A |
| 2018-10-01 | $98.45 | Not available in this setting | RVU18D |
| 2018-07-01 | $98.45 | Not available in this setting | RVU18C |
| 2018-04-01 | $98.45 | Not available in this setting | RVU18B |
| 2018-01-01 | $98.45 | Not available in this setting | RVU18AR1 |
| 2017-10-01 | $98.92 | Not available in this setting | RVU17D |
| 2017-07-01 | $98.92 | Not available in this setting | RVU17C |
| 2017-04-01 | $98.92 | Not available in this setting | RVU17B |
| 2017-01-01 | $98.92 | Not available in this setting | RVU17A |
| 2016-10-01 | $98.98 | Not available in this setting | RVU16D |
| 2016-07-01 | $98.98 | Not available in this setting | RVU16C |
| 2016-04-01 | $98.98 | Not available in this setting | RVU16B |
| 2016-01-01 | $98.98 | Not available in this setting | RVU16A |
| 2015-10-01 | $98.17 | Not available in this setting | RVU15D |
| 2015-07-01 | $98.17 | Not available in this setting | RVU15C |
| 2015-04-01 | $97.68 | Not available in this setting | RVU15B |
| 2015-01-01 | $97.68 | Not available in this setting | RVU15A |
| 2014-10-01 | $94.37 | Not available in this setting | RVU14D |
| 2014-07-01 | $94.37 | Not available in this setting | RVU14C |
| 2014-04-01 | $94.37 | Not available in this setting | RVU14B |
| 2014-01-01 | $94.37 | Not available in this setting | RVU14A |
| 2013-10-01 | $95.68 | Not available in this setting | RVU13D |
| 2013-07-01 | $95.68 | Not available in this setting | RVU13C |
| 2013-04-01 | $95.68 | Not available in this setting | RVU13B |
| 2013-01-01 | $95.68 | Not available in this setting | RVU13AR |
Where the Connecticut rate applies
Connecticut is a Medicare payment area, not a city. Our Census mapping connects it to 215 cities and communities in Connecticut. Some span more than one payment area; confirm with the service ZIP.
- Ansonia
- Ball Pond
- Baltic
- Bantam
- Bethel
- Bethlehem Village
- Bigelow Corners
- Blue Hills
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
Fee sheets
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