Verify benefits and obtain prior authorization when required

Coverage and reimbursement are conditional on the member's benefit coverage and demonstration of medical necessity; providers should verify benefits and obtain prior authorization if required by the member's benefit plan or payer rules.

• Coverage requires meeting authorization and medical necessity guidelines at time of service.
• Prior authorization may be required per member benefits and payer rules (not enumerated in this policy).

Prior authorization not specified in policy text

This policy does not specify any universal prior authorization program for GGT testing in the excerpt; societies cited recommend using GGT as a confirmatory or second‑line test rather than routine first‑line screening.

• No explicit prior authorization requirements are stated in this section.
• ACG and CAG recommend GGT be used to confirm elevated ALP or as a second‑line biochemical test.

Use CPT code 82977 and follow payer authorization rules

Procedure code 82977 (Glutamyltransferase, gamma [GGT]) is the CPT code referenced; any payer-specific prior authorization, billing rules, or government policy precedence should be applied to claims using this code.

• Referenced CPT code: 82977 — Glutamyltransferase, gamma (GGT).
• Any prior authorization requirements for this code follow applicable payer or government policies and may be superseded by LCD/NCDs.

No step therapy required

No step therapy requirements are described in this policy excerpt; clinical guidance instead advises using GGT for confirmation of elevated alkaline phosphatase or as part of follow-up/liver evaluation rather than as a population screening tool.

• Policy text: no step therapy sequence is specified.
• Guidelines suggest GGT is a second‑line or confirmatory test when liver chemistries are abnormal.

Follow guideline-recommended sequencing with ALT and other liver tests

Guidelines recommend measuring GGT alongside ALT (and other liver tests) to identify recent heavy alcohol use and as part of initial liver blood test evaluation when screening tests are abnormal.

• ASAM recommends measurement of GGT and ALT to identify recent heavy alcohol use.
• BSG recommends initial liver investigation include bilirubin, albumin, ALT, ALP and GGT (with a full blood count if not done within 12 months).

Document medical necessity and code correctly

Ordering must be consistent with medical necessity and the member's benefit coverage; providers are responsible for accurate coding and submission of documentation to justify the test and its frequency.

• Submit accurate documentation of services performed and evidence that criteria are met (e.g., elevated ALP or listed clinical conditions).
• Claims may be denied or recouped if coding/billing guidelines or current reimbursement policies are not followed.

Avoid ordering GGT for asymptomatic screening

Ordering GGT for asymptomatic individuals during a wellness visit or general exam without abnormal findings does not meet criteria and may be denied.

• Policy excludes GGT testing during routine wellness visits or general exams in asymptomatic individuals without abnormal findings.
• Routine screening with GGT alone for liver disease in the absence of other abnormal liver chemistries is not supported.

Apply government policies when they conflict with this policy

If this Policy conflicts with an applicable government policy (e.g., LCDs/NCDs or state Medicaid), the government policy will take precedence and determine coverage.

• When government policy applies, it supersedes this policy for coverage determinations.
• Verify applicable Medicare/Medicaid coverage at the time of the request.

Include clinical evidence to support medical necessity

Providers must supply documentation demonstrating that testing meets the policy criteria — for example, evidence of elevated alkaline phosphatase or one of the listed clinical conditions — and support the requested testing frequency.

• Provide clinical evidence (e.g., elevated ALP or listed conditions) to support medical necessity.
• Ensure documentation justifies testing frequency (policy allows GGT no more than once every two weeks for covered indications).

Order GGT to confirm hepatic origin or as a second‑line test per guidelines

Guideline recommendations in this policy state GGT should be used to confirm hepatic origin of isolated alkaline phosphatase elevation and as a second‑line biochemical test when at least one liver screening test is abnormal.

• ACG: confirm elevated ALP with an elevated GGT before further evaluation; GGT should not be used for screening absent other abnormal chemistries.
• CAG: patients with at least one abnormal liver screening test should have GGT, albumin, bilirubin and PT/INR performed.

Include GGT in initial liver panel per BSG guidance

Initial investigation for potential liver disease should include bilirubin, albumin, ALT, ALP and GGT, together with a full blood count if not performed within the previous 12 months.

• BSG recommends this initial panel as part of evaluation for potential liver disease.
• If a full blood count was done within 12 months, repeating may not be necessary.