Coding, claims, denials and AR follow-up for independent GI groups, endoscopy centers, IBD infusion suites and the anesthesia teams that work beside them.
A screening colonoscopy that ends in a snare polypectomy pays the gastroenterologist $223.45 in a facility under the 2026 Medicare fee schedule, and the same case can produce an anesthesia claim, a pathology claim and an ASC facility claim. Leave modifier PT off and the claim can process with the deductible applied, so the patient gets a bill for a screening. Luxen codes and follows up every claim from the case inside your current system, with certified coders and a BAA signed before access.
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Gastroenterology billing services code, submit and follow up on claims for GI practices: office visits, colonoscopy and EGD, anesthesia, pathology, ASC facility and biologic infusion claims. The costly errors cluster around screening. 14% of screening colonoscopies that converted to diagnostic were billed without the PT or 33 modifier, across 9,800 GI claims (Luxen claim audit).
GI billing changes with where the scope happens and who owns the room.
Service lines we bill: professional endoscopy, ASC facility claims, anesthesia (00811 to 00813), surgical pathology (88305), capsule endoscopy (91110), hemorrhoid banding (46221) and biologic infusion (96413), with eligibility and prior authorization checks done before the procedure.
Most lost GI revenue sits between the procedure note and the several claims that follow it. Our denials and AR recovery team works these claims oldest dollars first. Amounts are 2026 Medicare national rates, facility setting unless noted.
| Scenario | Codes | What goes wrong | $ at stake per claim | Luxen audit finding |
|---|---|---|---|---|
| Screening turns into a polypectomy | 45385-PT (Medicare), 45385-33 (commercial) | Modifier missing, so cost sharing lands on a screening | $223.45 professional claim reprocessed | 14% of screening colonoscopies that converted to diagnostic were billed without the PT or 33 modifier, across 9,800 GI claims |
| Anesthesia for a converted screening | 00811-PT instead of 00812 | Anesthesia claim keeps the screening code or drops PT | $20.50 per base unit, or the full claim if denied | Anesthesia claims for GI endoscopy were denied 2.4 times as often as the procedure claims |
| Biopsy and snare removal on separate polyps | 45385 with 45380-XS | No XS, so the biopsy bundles; or XS on the same lesion, recouped on audit | $13.02 facility, $101.87 office, after the multiple endoscopy reduction | Multiple endoscopy base-code ranking errors underpaid 9% of multi-procedure sessions |
| Pathology waiting on the report | 88305 per specimen | Specimens stay unbilled until someone matches the report to the case | $70.14 global per specimen | Pathology charges were billed a median 11 days after the procedure |
| ASC case with two claims | ASC facility claim and 45385 | Facility and professional claims list different codes, so one is held | $223.45 professional plus the facility payment | Facility and professional claims disagreed on codes in 6% of ASC cases |
| IBD biologic infusion | 96413 plus the drug J code | Reauthorization lapses between infusions | $133.27 administration (office) plus the drug line | Lapsed biologic re-authorizations caused 31% of GI infusion denials |
Amounts below are 2026 Medicare national payments at the $33.4009 conversion factor, before locality and sequestration adjustments. They already include the 2.5% efficiency adjustment CMS applied to work RVUs of non-time-based services such as endoscopy. Our certified medical coders check each case against the procedure note before it bills.
| Code | Service | Facility | Office | Billing note |
|---|---|---|---|---|
| G0121 | Screening colonoscopy, not high risk | $165.00 | $378.43 | Medicare only; once every 10 years |
| G0105 | Screening colonoscopy, high risk | $164.67 | $378.10 | Medicare only; every 24 months |
| 45378 | Diagnostic colonoscopy | $164.67 | $378.10 | Base code for the colonoscopy family |
| 45380 | Colonoscopy with biopsy, single or multiple | $177.69 | $479.97 | One unit however many biopsies |
| 45384 | Colonoscopy, removal by hot biopsy forceps | $203.41 | $539.42 | Same family as 45378 |
| 45385 | Colonoscopy, removal by snare | $223.45 | $500.01 | Add PT or 33 when a screening converts |
| 43235 | Diagnostic EGD | $110.56 | $322.65 | Base code for the EGD family |
| 43239 | EGD with biopsy | $123.58 | $418.85 | Paid at 50% beside a colonoscopy |
| Code | Service | Facility | Office | Billing note |
|---|---|---|---|---|
| 88305 | Surgical pathology, per specimen | $70.14 global | $70.14 global | $35.07 each for -26 and -TC |
| 91110 | Capsule endoscopy, esophagus through ileum | $802.29 global | $802.29 global | Billed global, -26 or -TC |
| 46221 | Internal hemorrhoid banding | $197.07 | $325.66 | 10-day global period |
| G0500 | Moderate sedation by the endoscopist, first 15 minutes | $5.34 | $66.47 | Requires an independent trained observer; 99153 for added time |
Medicare pays G0121 for patients not at high risk once every 10 years, or 47 months after a screening flexible sigmoidoscopy, and G0105 for high-risk patients every 24 months (42 CFR 410.37). CMS applies a minimum age of 45 to both codes from January 1, 2023. High risk means a parent, sibling or child with colorectal cancer or an adenomatous polyp, a personal history of adenomatous polyps or colorectal cancer, a family history of FAP or HNPCC, or inflammatory bowel disease.
Bill the therapeutic code with modifier PT for Medicare (45385-PT) or modifier 33 for commercial plans (45385-33). Medicare still waives the deductible, and coinsurance follows the phase-down in 42 CFR 410.152(l)(5):
| Date of service | Medicare coinsurance | Patient share of 45385 in a facility |
|---|---|---|
| 2023 to 2026 | 15% | $33.52 |
| 2027 to 2029 | 10% | $22.35 |
| 2030 onward | 0% | $0.00 |
Non-grandfathered ACA plans cannot charge cost sharing for polyp removal during a screening colonoscopy (FAQs Part XII), for anesthesia the physician finds medically appropriate (Part XXVI) or for pathology on the removed polyp (Part XXIX). Our patient billing team explains any Medicare coinsurance before the statement goes out.
Medicare treats a colonoscopy after a positive Medicare-covered stool-based test as screening from 2023, and after a positive blood-based biomarker test from 2025. Report it with modifier KX, and add PT to the procedure code if tissue is removed (CMS Transmittal 12299). ACA plans must cover the follow-on colonoscopy after a positive stool-based test without cost sharing for plan years beginning on or after May 31, 2022 (FAQs Part 51).
Endoscopies that share a base code form a family. Medicare pays the highest-valued code at 100% and each other code in the family at its value minus the base code. A second family, such as an EGD in the same session, is then paid at 50% (Noridian endoscopy payment rules). Noridian instructs billers not to append modifier 51, because the claims system applies the reductions.
| Line | Code | 2026 facility rate | Paid |
|---|---|---|---|
| Snare polypectomy | 45385 | $223.45 | $223.45 |
| Biopsy of a separate polyp | 45380-XS | $177.69 | $13.02 ($177.69 minus 45378 at $164.67) |
| EGD with biopsy, second family | 43239 | $123.58 | $61.79 (50%) |
| Session total | $298.26 |
A biopsy is billed separately only when it is taken from a separate lesion, or when an immediate pathology result leads to a more extensive procedure on the same lesion (NCCI Policy Manual, Chapter I). The 45385 and 45380 edit may be bypassed with modifier 59 or XS only when the two procedures are on separate lesions (Chapter VI). Multiple biopsies still report 45380 once.
When a colonoscopy does not reach the cecum, the physician bills 45378, G0105 or G0121 with modifier 53, and Medicare pays it using one-half the value of the inputs (Claims Processing Manual, Chapter 12, section 30.1). The ASC reports the same code with modifier 73 or 74.
Surgical pathology 88305 bills per specimen, globally or split into -26 and -TC when the reading and the lab are separate entities. Capsule endoscopy 91110 splits the same way (CGS article A56461). When an in-network ASC uses an out-of-network anesthesiologist or pathologist, California Health and Safety Code 1371.9 (AB 72) limits patients in state-regulated health plans to in-network cost sharing (medical billing in California).
46221 carries a 10-day global period, so routine follow-up inside it is not billed. Under NCCI, a diagnostic anoscopy (46600) is not separately reportable with an anal procedure in the same session, and several hemorrhoid treatments in one encounter report only the most extensive.
Medicare waives the deductible when tissue is removed during a screening colonoscopy and limits coinsurance to 15% through 2026 (42 CFR 410.152), and non-grandfathered ACA plans cannot charge cost sharing for the polypectomy (ACA FAQs Part XII). Billing without PT or 33 sends a bill the patient should not owe. Practices lost 3.1% of collections to patient balances written off before a second statement (Luxen client data).
Once a screening converts, Medicare requires 00811 with modifier PT instead of 00812 (CMS Transmittal 12299), and Noridian does not accept PT on 00813 (Noridian colorectal cancer screening). The anesthesia claim is worth one more base unit, $20.50 nationally, and draws denials when it does not match the procedure claim. Anesthesia claims for GI endoscopy were denied 2.4 times as often as the procedure claims (Luxen claim audit).
NCCI allows 45380 with 45385 only when the biopsy and the removal are on separate lesions (NCCI Policy Manual, Chapter VI). Even then Medicare pays the biopsy at $13.02 in a facility, and XS on a same-lesion biopsy is recouped on audit. Coding and modifier errors caused 21% of denials (Luxen claim audit).
Medicare has treated it as screening since 2023, reported with modifier KX (42 CFR 410.37), and ACA plans must cover it without cost sharing for plan years beginning on or after May 31, 2022 (ACA FAQs Part 51). Billing it as diagnostic puts the deductible on a claim that should not carry it. Eligibility and coverage errors caused 24% of denials (Luxen claim audit).
Z86.010 ended September 30, 2024. Claims from October 1, 2024 need Z86.0100, Z86.0101, Z86.0102 or Z86.0109 (CMS Transmittal 13025). A surveillance G0105 with the retired code rejects, holding $164.67 in a facility. 19% of denied claims were never reworked or appealed (Luxen billing reviews).
We run the revenue cycle from eligibility to zero balance inside the practice management system you already use. How full-service billing works.
Certified coders review charges against your documentation and payer rules before the claim goes out, so the denial is prevented rather than appealed. Medical coding.
Aged and denied claims are worked to resolution, then the upstream cause is fixed so the same claims stop coming back. Denials and AR recovery.
Benefits are verified and authorizations secured before the appointment, which is the cheapest place in the cycle to stop a denial. Eligibility and prior authorization.
Statements, balance questions and payment plans are handled by the same team that worked the claim. Patient billing.
Payer enrollment and re-credentialing are tracked through to approval, so a lapsed credential never quietly stops payment. Credentialing.
A HIPAA-trained front-office assistant working inside your EHR on calls, scheduling, intake and referrals, alongside the billing team. Medical virtual assistant.
We bill inside the systems your GI practice already runs, with no migration.
38% had changed EHR or practice management system in the past five years, and of those, 71% said collections dipped for at least six months after the switch (Luxen Practice Manager Survey 2026). We sign the BAA first and work from the procedure notes, pathology reports and schedules you already keep.
2 weeks
from a signed BAA to our team working your claims
About 3 weeks
to the first recovered payments on aged AR
20+ years
combined billing and coding experience
Gastroenterology findings from the Luxen claim audit (61,400 claims audited, Jan 2025 to Jun 2026) and Luxen billing reviews (410 practice billing reviews, Jan 2025 to Jun 2026):
The endoscopy schedule, procedure note, and pathology order were handled in separate systems. Luxen reconciled each case, identified 154 missing services, and recovered $71,800 during the first quarter.
Practice Administrator, gastroenterology and endoscopy group
Claims with multiple procedures were regularly returned for bundling and modifier issues. Luxen added a pre-submission coding review, reduced those denials from 18% to 5%, and recovered $63,500 from the backlog.
Billing Director, multi-provider digestive health practice
Full engagements are written up in our dental practice case study and our ambulance billing case study.
| KPI | Luxen benchmark | GI check |
|---|---|---|
| First-pass denials | Across 38 client practices, first-pass denial rate fell from 14.2% to 6.1% within 90 days of onboarding | Split procedure, anesthesia and pathology denials |
| Days in AR | Median days in AR dropped from 54 to 33 within 120 days | Track ASC facility AR on its own |
| Net collection rate | Net collection rate rose from 91.4% to 97.8% over the first six months | Compare paid endoscopy lines to the multiple endoscopy math |
| Underpayments | Underpayments against contracted rates appeared on 7.8% of paid claims | Check screening lines paid with cost sharing |
| AR ageing review | Practices that reviewed AR ageing monthly carried 12 fewer days in AR | Review pathology and anesthesia ageing too |
Sources: Luxen client data (38 client practices, Jan 2024 to Jun 2026), Luxen claim audit (61,400 claims audited, Jan 2025 to Jun 2026) and Luxen billing reviews (410 practice billing reviews, Jan 2025 to Jun 2026).
3% to 6% of collections
Luxen's pricing generally falls between 3% and 6% of collections, depending on claim volume, specialty, payer mix, and how much of the revenue cycle your practice hands over.
Higher-volume practices usually land toward the lower end. Smaller or more complex practices land higher because there is more work per account. There is no setup fee and no exit fee, and the agreement runs month to month with 30 days notice.
A lower fee attached to weak billing is still expensive. The number that matters is what your collections do after you hire someone.
Luxen charges 3% to 6% of collections, set by procedure volume, ASC and anesthesia lines, and authorization workload. No setup or exit fee.
| Service line | Monthly collections | Luxen at 3% | Luxen at 6% |
|---|---|---|---|
| Professional endoscopy | $90,000 | $2,700 | $5,400 |
| Office visits, capsule and motility studies | $35,000 | $1,050 | $2,100 |
| Anesthesia for endoscopy | $20,000 | $600 | $1,200 |
| Biologic infusion | $15,000 | $450 | $900 |
| Total | $160,000 | $4,800 | $9,600 |
| Cost | In-house | Luxen |
|---|---|---|
| Monthly | $12,640 (7.9% of collections) | $4,800 to $9,600 |
| Annual | $151,680 | $57,600 to $115,200 |
| When a biller leaves | Open biller roles took a median 67 days to fill | Coverage continues |
| Terms | Salaries, benefits, software and coding education | Month to month, 30 days notice |
Fully loaded in-house billing cost 7.9% of collections for practices under $2M, across 96 practices that shared payroll data (Luxen billing reviews). This example practice collects $1.92M a year.
| Partner type | Screening modifier checks | ASC, anesthesia and pathology | Reporting | Terms |
|---|---|---|---|---|
| In-house biller | Depends on one person | Often split across staff | Built by your team | Payroll and turnover |
| Generalist billing company | Usually after a denial | Often professional claims only | Standard aging | Often annual |
| Specialty GI billing company | Usually built in | Varies by vendor | Varies | Varies |
| EHR vendor RCM | Software edits | Limited outside the platform | Inside the platform | Tied to the software contract |
| Luxen | Pre-bill check on every screening case | Included | Monthly denials and AR by procedure, payer and claim type | Month to month, 30 days notice |
Compare medical billing companies, or see what full-service medical billing includes.
A 30-minute look at your AR ageing, denial reasons and payer mix. You leave knowing what is recoverable, what we would work first and what it would cost.
We sign a business associate agreement before anyone touches your system. Your named team then works inside the practice management system and clearinghouse you already use. Nothing is migrated, and claims are being worked within two weeks of the signed BAA.
Aged and denied claims come first because that is revenue you have already earned. Most practices see the first recovered payments inside three weeks.
Once the backlog is moving, we take over the agreed part of the daily cycle: eligibility, coding review, submission, posting, denials and patient balances.
You know who owns your claims. The team works inside the practice management system and EHR you already run, with no migration.
Claims are coded by certified coders against your documentation and payer rules. Automation handles the repetitive checks so people spend their time on the claims that need judgment.
We sign a business associate agreement before accessing protected health information, and access is limited to the named people on your account.
We look at your AR ageing, volume, payer mix and denial profile first, then tell you what we believe is recoverable and what it would cost.
A billing company is a poor fit if you are not willing to share visibility into your billing, if the vendor uses a rotating pool of people who never learn your practice, or if it cannot explain why your claims are being denied. Be wary of anyone promising large collection increases before they have seen your AR ageing. The right partner makes your revenue cycle more visible, not less.
Coding and claim submission for office visits, colonoscopy and EGD, plus anesthesia, pathology, ASC facility and infusion claims, then denial and AR follow-up. A GI biller also has to apply screening rules, such as modifier PT for Medicare and modifier 33 for commercial plans. Luxen adds eligibility and prior authorization checks before the procedure and works inside your existing EHR.
Luxen charges 3% to 6% of collections, with no setup or exit fee. For a practice collecting $160,000 a month, that is $4,800 to $9,600 a month. Fully loaded in-house billing cost 7.9% of collections for practices under $2M, across 96 practices that shared payroll data (Luxen billing reviews).
About 2 weeks from signed BAA to working claims. Median time from signed BAA to first claims worked was 9 business days, and first recovered payments arrived a median of 17 days after work began (Luxen client data). We start with the oldest AR, including unbilled pathology and anesthesia charges.
Yes. We work inside ModMed Gastroenterology (gMed), Epic, athenaOne, eClinicalWorks and NextGen, and code from Provation or EHR endoscopy reports. There is no migration, and that matters: 38% had changed EHR or practice management system in the past five years, and of those, 71% said collections dipped for at least six months after the switch (Luxen Practice Manager Survey 2026).
Yes, with limits. Medicare waives the deductible but charges 15% coinsurance through 2026, falling to 10% in 2027 and 0% in 2030, and the claim needs modifier PT. Non-grandfathered ACA plans cannot charge cost sharing for polyp removal during a screening colonoscopy, and the claim should carry modifier 33.
Thirty minutes, no deck and no fee. We look at what is sitting past 90 days and where your denials cluster, and you leave knowing what is recoverable, what we would work first, and what it would cost.
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