CurrentBlue Cross Blue Shield - TennesseePolicy N/A

Vitamin B12 and Methylmalonic Acid Testing

Coverage criteria for laboratory testing of total vitamin B12, methylmalonic acid (MMA), homocysteine, and holotranscobalamin for diagnosis or monitoring of vitamin B12 deficiency, as applied by BlueCross BlueShield of Tennessee.

Policy Summary

PayerBlue Cross Blue Shield - Tennessee

PolicyVitamin B12 and Methylmalonic Acid Testing

Policy CodePolicy N/A

Change TypeNo material changes

Effective Date

Next Review Date

Key ActionOrder total serum B12 (with CBC) for symptomatic or at-risk patients and document signs, symptoms, or risk factors to support coverage; consider MMA when serum B12 is low-normal or indeterminate.

SourceLink

POLICY UPDATE CHANGES

No material clinical or coverage changes in this revision.

every 3 monthsmax testing frequency

Not coveredholotranscobalamin

Not coveredhomocysteine

3→annualpost-bariatric schedule

>95%elevated MMA sensitivity

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Coverage Criteria for Vitamin B12 and Related Tests

Total Vitamin B12 — Covered Indications

Covered when ANY of the following are met (total vitamin B12 testing meets coverage criteria once every three months):

Signs or symptoms of B12 deficiency: Total vitamin B12 testing is covered for individuals with listed signs and symptoms of deficiency (cutaneous: hyperpigmentation, jaundice, vitiligo; gastrointestinal: glossitis; hematologic: anemia [macrocytic, megaloblastic], leukopenia, pancytopenia, thrombocytopenia, thrombocytosis; neuropsychiatric: areflexia, cognitive impairment including dementia-like symptoms or acute psychosis, gait abnormalities, irritability, loss of proprioception/vibratory sense, olfactory impairment, peripheral neuropathy).once every three months

Individuals undergoing treatment: Total vitamin B12 testing is covered for individuals undergoing treatment for vitamin B12 deficiency.once every three months

Documentation should support treatment monitoring

Risk factors for deficiency: Total vitamin B12 testing is covered for individuals with one or more of the following risk factors: decreased ileal absorption (Crohn disease, ileal resection, tapeworm infection, prior or planned bariatric procedures such as Roux-en-Y gastric bypass, sleeve gastrectomy, biliopancreatic diversion/duodenal switch); decreased intrinsic factor (atrophic gastritis, pernicious anemia, postgastrectomy syndrome); transcobalamin II deficiency; inadequate intake (alcohol abuse, age >75 years or evaluation for dementia, vegan/strict vegetarian including exclusively breastfed infants of vegan mothers, eating disorder); prolonged medication use (histamine H2 blockers >12 months, metformin >4 months, proton pump inhibitors >12 months).once every three months

Methylmalonic Acid (MMA) — Covered Indications

Covered when ANY of the following are met (MMA):

Confirmatory testing in specific contexts: Methylmalonic acid (MMA) testing meets coverage criteria in asymptomatic high-risk individuals with low-normal vitamin B12 or when vitamin B12 deficiency is suspected but serum vitamin B12 is normal or low-normal.

Used as a second-line metabolic marker to confirm functional deficiency

Inborn errors of metabolism: Methylmalonic acid testing meets coverage criteria for evaluation of inborn errors of metabolism.

Not Medically Necessary / Not Covered

Not covered:

Screening in healthy asymptomatic individuals: Screening for vitamin B12 deficiency in healthy, asymptomatic individuals does not meet coverage criteria.

May be denied if ordered for population screening

Homocysteine for confirmation: Homocysteine testing for confirmation of vitamin B12 deficiency does not meet coverage criteria.

Alternative metabolic marker but not covered for confirmation per policy

Holotranscobalamin testing for screening, testing, or confirmation of vitamin B12 deficiency does not meet coverage criteria.

Emerging marker but not covered

Other situations: Total vitamin B12 testing for all other situations not described above does not meet coverage criteria.

Society-based testing and monitoring recommendations

Testing and monitoring recommended in specific clinical contexts per cited societies:

Indications for testing per societies: Order serum vitamin B12 (with complete blood count) for patients with suspected vitamin B12 deficiency or listed clinical manifestations (cutaneous, gastrointestinal, hematologic, neuropsychiatric signs) as described by professional societies.

AAFP and others recommend targeted diagnostic testing rather than routine screening

When to add MMA or homocysteine: If serum vitamin B12 is normal or low-normal but clinical suspicion persists (for example macrocytosis or neurologic symptoms), or in patients post-bariatric surgery or with history of B12 deficiency/neuropathy, measure methylmalonic acid (with or without homocysteine) to identify metabolic deficiency.

ASMBS and other guidelines support MMA as second-line test

Screening guidance: Routine screening of average-risk asymptomatic patients is not recommended; consider supplementation without testing or targeted testing in asymptomatic patients with risk factors.

The Doctors of BC and AAFP positions cited

Coverage-informed clinical criteria

Testing and monitoring recommendations summarized from cited guidelines (used to inform coverage determinations):

Post-bariatric surgery monitoring: Baseline and annual evaluation for vitamin B12 is recommended for all patients after bariatric procedures; more frequent monitoring (eg, every 3 months) is recommended during the first postoperative year (check at 3, 6, and 12 months) and then at least annually thereafter. Include additional nutrient monitoring for malabsorptive procedures and assess during pregnancy each trimester.

Supports frequency limits in coverage criteria

Use of metabolic markers: Measure serum methylmalonic acid (with or without homocysteine) when serum vitamin B12 may be inadequate to identify deficiency, in symptomatic or asymptomatic patients with history of deficiency or neuropathy, and to monitor treatment effectiveness when available.

Consensus panel and ASMBS recommend MMA as useful metabolic marker

Metformin-associated monitoring: Consider periodic (eg, annual) assessment of vitamin B12 in patients on chronic metformin to detect deficiency prior to neuropathy.Once per year

Screening for vitamin B12 deficiency in healthy, asymptomatic individuals is explicitly not supported by this policy. The policy also states that holotranscobalamin testing and homocysteine testing for confirmation do not meet coverage criteria and may be denied; methylmalonic acid (MMA) testing is reserved for specific confirmatory or metabolic indications (e.g., asymptomatic high-risk with low‑normal B12 or evaluation of inborn errors of metabolism).

Professional society guidance cited in the policy aligns with the stance against routine population screening: the AAFP does not recommend screening persons at average risk and The Doctors of BC states that routine B12 screening and testing in asymptomatic patients is not supported by evidence. Both sources advise targeting testing to patients with risk factors or suspected clinical manifestations rather than broad asymptomatic screening.

For patients with neuropathy, the BMJ review emphasizes that serum biomarkers (including serum B12 and MMA) are unreliable predictors of B12‑responsive neuropathy. Biomarkers often normalize more quickly than clinical recovery, and repeated measurement of these markers is not helpful for assessing or guiding recovery; clinical monitoring of symptoms should direct treatment adjustments rather than routine biomarker surveillance.

The cited evidence references in this section do not contain any additional explicit coverage exclusions beyond those stated elsewhere in the policy.

The policy makes clear that screening for vitamin B12 deficiency in healthy, asymptomatic individuals does not meet coverage criteria and may be denied when ordered without documented risk factors or clinical indications.

Although B12 supplementation lowers homocysteine levels in meta‑analyses, pooled evidence does not demonstrate that supplementation reduces cardiovascular events. The policy therefore indicates that vitamin B12 should not be used for cardiovascular disease prevention, and reductions in homocysteine alone do not justify routine testing or supplementation for this purpose.

Routine serial measurement of biomarkers solely to document clinical improvement in neuropathy is not indicated: biomarkers such as serum B12 or MMA can normalize before symptoms improve and do not reliably predict clinical recovery. Providers should base treatment frequency and adjustments on symptom monitoring rather than on biomarker trends alone.

These referenced evidence sections do not include any explicit additional determinations labeled as 'not medically necessary' beyond the policy statements summarizing guideline and evidence positions.

Covered Indications and Clinical Scenarios

Total vitamin B12 testing for signs/symptoms of deficiency, for individuals undergoing treatment, or for those with specified risk factors.

Covered when ANY of the following are met (total vitamin B12 testing meets coverage criteria once every three months):

Signs or symptoms of B12 deficiency: Total vitamin B12 testing is covered for individuals with listed signs and symptoms of deficiency (cutaneous: hyperpigmentation, jaundice, vitiligo; gastrointestinal: glossitis; hematologic: anemia [macrocytic, megaloblastic], leukopenia, pancytopenia, thrombocytopenia, thrombocytosis; neuropsychiatric: areflexia, cognitive impairment, gait abnormalities, irritability, loss of proprioception/vibratory sense, olfactory impairment, peripheral neuropathy).once every three months

Individuals undergoing treatment or monitoring: Total vitamin B12 testing is covered for individuals undergoing treatment for vitamin B12 deficiency (testing meets coverage criteria once every three months).once every three months

Documentation should support treatment monitoring

Specified risk factors: Total vitamin B12 testing is covered for individuals with specified risk factors such as decreased ileal absorption, decreased intrinsic factor, transcobalamin II deficiency, inadequate intake, or prolonged medication use (see policy for full list).once every three months

Methylmalonic acid testing for asymptomatic high-risk individuals with low-normal B12 or suspected deficiency with normal/low-normal serum B12; and for evaluation of inborn errors of metabolism.

Covered when ANY of the following are met (MMA):

Asymptomatic high-risk with indeterminate B12: Methylmalonic acid testing is covered for asymptomatic high-risk individuals with low-normal vitamin B12 or when B12 deficiency is suspected but serum B12 is normal or low-normal; MMA is a useful metabolic marker to confirm deficiency.

Evaluation of inborn errors of metabolism: Methylmalonic acid testing is covered for evaluation of inborn errors of metabolism.

Supported by guideline citations

Suspected vitamin B12 deficiency with clinical manifestations (neurologic, hematologic, cutaneous, GI) and pre- and post-bariatric surgery screening and monitoring.

Covered when ANY of the following are met:

Clinical manifestations prompting testing: Suspected vitamin B12 deficiency with clinical manifestations (neurologic, hematologic, cutaneous, gastrointestinal) — initial laboratory evaluation should include a complete blood count and serum vitamin B12 level; if serum B12 is normal/low-normal with macrocytosis or suspected manifestations, measure serum methylmalonic acid as the next step.

AAFP recommended initial workup

Pre- and post-bariatric surgery screening and monitoring: Pre-weight-loss-surgery (pre-WLS) routine B12 screening is recommended for all candidates. Post-WLS surveillance: baseline and frequent monitoring in the first postoperative year (eg, at 3, 6, and 12 months) and then at least annually; include MMA (with or without homocysteine) as indicated and evaluate additional nutrients for malabsorptive procedures.first year: every 3 months; thereafter: at least annually

ASMBS and BOMSS guidance

Post-bariatric surgery surveillance — Baseline, frequent monitoring in first year (3,6,12 months), then at least annually; include additional nutrients for malabsorptive procedures.

Post-bariatric surgery surveillance recommendations:

Baseline and frequent monitoring first year: Baseline evaluation and more frequent surveillance (eg, every 3 months during the first postoperative year with checks at 3, 6, and 12 months) is recommended for patients undergoing bariatric procedures; thereafter monitor at least annually.3, 6, 12 months in first year; then at least annually

Include additional nutrients for malabsorptive procedures and assess during pregnancy each trimester

Use metabolic markers post-WLS: Consider measuring serum methylmalonic acid (with or without homocysteine) in symptomatic or asymptomatic post-bariatric patients and those with history of B12 deficiency or neuropathy because serum B12 alone may be inadequate to identify deficiency.

ASMBS/Mechanick consensus

Chronic metformin use — Periodic (annual) B12 measurement recommended to detect deficiency prior to neuropathy.

Monitoring recommendation for patients on chronic metformin:

Periodic B12 assessment: Consider periodic (eg, annual) assessment of vitamin B12 in patients on chronic metformin to detect deficiency prior to clinical neuropathy.Once per year

ADA recommendation; consider more frequent monitoring if other risk factors present

Symptoms or risk factors for B12 deficiency — Targeted testing when common symptom AND common risk factor are present; consider initial B12 or holotranscobalamin and follow-up metabolic markers.

Targeted testing for symptoms or risk factors:

Symptoms plus risk factors: Perform targeted testing when patients exhibit both common symptoms and common risk factors for B12 deficiency; initial testing may be total serum B12 or holotranscobalamin and follow-up metabolic markers (MMA or homocysteine) if results are indeterminate.

NICE recommends testing when symptom plus risk factor present; clinical judgment when symptoms alone

Diagnosis and management of vitamin B12 deficiency and related remethylation disorders — Supported by multiple guideline citations (e.g., Devalia 2014; Huemer 2017; Obeid 2024).

Diagnosis and management recommendations supported by guideline citations:

Guideline-supported management: Diagnosis and management of vitamin B12 deficiency and related remethylation disorders are supported by multiple guideline citations (for example Devalia 2014; Huemer 2017; Obeid 2024); guidelines recommend use of metabolic markers such as MMA to guide diagnosis and to monitor treatment when available.

Refer to listed guideline literature for details

Frequency Limits and Monitoring Intervals

inv-51: Total vitamin B12 (serum cobalamin) — once every three months

TestTotal vitamin B12 (serum cobalamin)

Frequency limitMeets coverage criteria once every three months

Applicable situationsSigns or symptoms of B12 deficiency, individuals undergoing treatment, or specified risk factors

inv-52: Vitamin B12 (and as indicated MMA/Homocysteine) — More frequent (e.g., every 3 months) in first postoperative year; then at least annually or as clinically indicated.

TestVitamin B12 (with MMA and/or homocysteine as indicated)

Frequency guidanceMore frequent monitoring (e.g., every 3 months) in the first postoperative year; then at least annually or as clinically indicated

ContextRoutine post-WLS surveillance and patients on medications that increase deficiency risk (e.g., metformin, PPIs)

inv-53: Vitamin B12 (and additional nutrients as indicated) — Baseline, every 3 months during first postoperative year, then at least annually

TestsVitamin B12 and additional nutrients (with MMA as indicated)

Baseline and early follow-upBaseline testing pre‑procedure and every 3 months during the first postoperative year

Long-term follow-upThen at least annually; include other nutrient monitoring for malabsorptive procedures and during pregnancy

inv-54: Vitamin B12 status — Once per year

PopulationPatients on long-term metformin (type 2 diabetes) and similar chronic-risk groups

Recommended frequencyAssess B12 status once per year to detect deficiency prior to clinical manifestation

RationaleChronic metformin use is associated with lower plasma B12 and linked to neuropathy risk

inv-55: (placeholder) Additional frequency notes.

Postoperative intensificationIncrease monitoring frequency (e.g., every 3 months) during the first year after bariatric surgery

Pregnancy after WLSPerform nutritional surveillance and laboratory screening each trimester for patients who become pregnant after bariatric procedures

Benefit verificationVerify member benefits and applicable government policies prior to ordering tests

Provider Actions, Documentation, and Billing Notes

Documentation Required

Benefit verification required — Government policy precedence

Application of coverage criteria is dependent upon an individual's benefit coverage at the time of the request. Specifications pertaining to Medicare and Medicaid take precedence when applicable; verify Local Coverage Determinations (LCDs), National Coverage Determinations (NCDs), or state Medicaid rules for the member prior to ordering.

Verify Medicare/Medicaid specifications and applicable government policies prior to determination.
When government policy conflicts with this policy, government policy prevails.

Documentation Required

Post‑WLS testing recommendation

Routine post-weight-loss-surgery (WLS) screening of vitamin B12 status is recommended for patients who have undergone Roux-en-Y gastric bypass, sleeve gastrectomy, or biliopancreatic diversion/duodenal switch. More frequent screening (for example, every 3 months) is recommended in the first postoperative year and then at least annually or as clinically indicated; include serum methylmalonic acid (MMA) with or without homocysteine to identify metabolic B12 deficiency when serum B12 may be inadequate.

Routine post‑WLS screening recommended for RYGB, SG, BPD/DS.
More frequent screening (e.g., every 3 months) in first post‑WLS year; then at least annually or as clinically indicated.
Consider serum MMA with or without homocysteine because serum B12 may not be adequate.

Billing Rule

Procedure code reference and PA note

Procedure codes listed are provided for reference only. Follow applicable payer or government-specific prior authorization and billing rules; codes may not be all-inclusive.

Reference CPT/HCPCS codes: 82607 (Cyanocobalamin / Vitamin B12), 83090 (Homocysteine), 83921 (Organic acid, single, quantitative), 84999 (Unlisted chemistry procedure).
Procedure codes in this policy are for general reference and may not be exhaustive.
Adhere to any payer-specific prior authorization processes before ordering tests.

Prior Authorization

Prior authorization (not specified)

No specific prior authorization requirements are stated in this section of the policy. Verify with the member's benefit plan or prior authorization portal for any payer- or plan-level requirements before testing.

This policy does not specify PA requirements — check member-specific benefit/PA systems.
When in doubt, obtain PA or pre-certification per the payer's rules.

Note

AAFP screening stance

The American Academy of Family Physicians (AAFP) does not recommend routine screening of average‑risk, asymptomatic individuals for vitamin B12 deficiency. Testing should be considered for patients with risk factors or suspected clinical manifestations.

Do not perform population screening in asymptomatic average‑risk individuals.
Consider testing for patients with listed risk factors or clinical signs/symptoms.

Denial Risk

No denial triggers specified in this reference section

There are no explicit denial triggers listed in this reference portion of the policy. Coverage decisions are based on documented clinical indications, risk factors, and applicable government/payer rules.

Absence of listed clinical indication may result in denial based on plan rules.
When denial is contemplated, document how the requested test meets coverage criteria and any applicable government policy.

Documentation Required

Supporting clinical documentation

Documentation should support signs/symptoms, risk factors, or treatment monitoring to meet coverage criteria for total vitamin B12 testing (up to once every three months when indicated). Include relevant clinical findings, medication history (e.g., metformin, PPIs), surgical history (e.g., bariatric procedures), and pregnancy status when applicable.

Document presenting signs/symptoms and at least one risk factor when applicable.
Include medication history (chronic metformin, PPI, H2 blocker), prior bariatric surgery, or dietary risk (veganism).
For monitoring, document the deficiency treatment course and rationale for repeat testing within 3 months.

Documentation Required

Initial diagnostic workup

Initial diagnostic workup for suspected vitamin B12 deficiency should include a complete blood count (CBC) and serum total vitamin B12 level. If serum B12 is low-normal or clinical suspicion remains, pursue methylmalonic acid (MMA) testing as the next step.

Order CBC and serum B12 as first‑line tests.
If serum B12 is low‑normal or clinical signs persist, obtain serum MMA to evaluate metabolic deficiency.
Holotranscobalamin and homocysteine are not recommended as standalone confirmatory tests per coverage guidance.

Documentation Required

Bariatric surgery follow‑up documentation

For post‑bariatric surgery follow‑up, consider measuring serum MMA with or without homocysteine to identify metabolic B12 deficiency, and perform more frequent monitoring during the first postoperative year and for patients on medications that increase deficiency risk.

Monitor at 3, 6, and 12 months in the first year, then at least annually.
Include MMA (with or without homocysteine) because serum B12 may be inadequate after malabsorptive procedures.
Increase frequency for patients on nitrous oxide, metformin, neomycin, colchicine, PPIs, or seizure medications.

Documentation Required

Clinical context required

Document clinical context such as bariatric surgery status, pregnancy trimester, chronic metformin or PPI use, neurological symptoms, hematologic abnormalities, dietary risk (vegan/vegetarian), or history of pernicious anemia to support medical necessity for testing.

Record specific signs/symptoms (e.g., neuropathy, cognitive changes, macrocytosis).
Note relevant risk factors: surgical history, medications, age >75, dietary intake, genetic conditions.
For pregnancy after bariatric surgery, document trimester surveillance plans.

Note

Therapy utility note

Meta-analyses show that vitamin B12 supplementation reduces homocysteine levels but does not reduce cardiovascular disease risk; B12 therapy should be used for treating deficiency and monitoring response, not as primary cardiovascular disease prevention.

B12 supplementation lowers homocysteine but has not demonstrated reduction in MI/stroke or cognitive decline.
Use B12 therapy for confirmed deficiency or clinically indicated treatment — not as routine cardiovascular prevention.

Documentation Required

Cascade testing approach

Consider a cascade testing approach: start with serum total B12 (or holotranscobalamin if available), and if results are low‑normal or inconsistent with the clinical picture, follow with metabolic markers such as methylmalonic acid (preferred) or homocysteine as indicated to confirm deficiency.

Initial test: serum total B12 (or holotranscobalamin where available).
Second step: serum MMA (preferred) or total homocysteine if MMA not available.
Reserve holotranscobalamin and homocysteine as adjuncts per availability and clinical context.

Definitions and Test Descriptions

inv-35: MMA — Methylmalonic acid (MMA): metabolite produced from methylmalonyl-CoA that accumulates when vitamin B12 is unavailable; used to indicate functional deficiency.

DefinitionMethylmalonic acid (MMA) is a metabolite produced from methylmalonyl-CoA that accumulates when vitamin B12 is unavailable

Clinical useUsed to indicate functional vitamin B12 deficiency and as a specific second-line measure

Additional noteMMA measurement is recommended when serum B12 is indeterminate or to monitor treatment effectiveness if available

inv-36: holoTC — Holotranscobalamin (holoTC): the metabolically active fraction of vitamin B12 representing biologically available cobalamin; an emerging marker.

DefinitionHolotranscobalamin (holoTC) is the metabolically active fraction of vitamin B12 representing biologically available cobalamin

Clinical roleAn emerging marker that may have sensitivity similar to total cobalamin but with uncertain specificity and limited availability

GuidanceNICE lists active B12 (holoTC) as an acceptable initial test except in pregnancy or suspected nitrous-oxide-related deficiency

inv-37: Methylmalonic acid (MMA) — Plasma test more specific second-line measure of functional vitamin B12 deficiency than homocysteine.

TestMethylmalonic acid (MMA) — plasma test

SpecificityMore specific second-line measure of functional vitamin B12 deficiency than homocysteine; sensitivity reported >95% for overt deficiency

Use caseRecommended when serum B12 is indeterminate or to clarify suspected deficiency (per BCSH/consensus guidance)

inv-38: Homocysteine — Homocysteine: a plasma marker elevated in B-vitamin metabolism disturbances but less specific than MMA; levels can be affected by folate/other factors.

DefinitionHomocysteine: a plasma marker elevated in B‑vitamin metabolism disturbances

LimitationsLess specific than MMA; levels can be affected by folate/pyridoxine deficiency, renal insufficiency, hypothyroidism, medications, and other conditions

RoleMay be used as a second-line or adjunctive marker when MMA is unavailable

inv-39: Holotranscobalamin — Holotranscobalamin: the metabolically active form of vitamin B12; sensitivity similar to total cobalamin but specificity uncertain and availability variable.

DefinitionHolotranscobalamin: the metabolically active form of vitamin B12

PerformanceSensitivity similar to total cobalamin; specificity remains uncertain and availability is limited

Clinical statusNot yet universally validated or widely available for clinical use

inv-40: Initial tests — Either total serum B12 (cobalamin) or active B12 (holotranscobalamin) is recommended as the initial test for suspected deficiency, except in special circumstances.

Initial testsEither total serum B12 (cobalamin) or active B12 (holotranscobalamin) is recommended as the initial test for suspected deficiency

ExceptionsExceptions include testing during pregnancy or when nitrous oxide exposure is suspected

RationaleUsing either initial test supports cascade testing with metabolic markers if results are indeterminate

inv-41: Metabolic markers — Plasma methylmalonic acid (MMA) or total homocysteine are metabolic markers useful for diagnosing and monitoring B12 deficiency, especially when serum B12 is equivocal.

MarkersPlasma methylmalonic acid (MMA) or total homocysteine are metabolic markers useful for diagnosis and monitoring

When to useUseful especially when serum B12 is equivocal or to monitor treatment effectiveness when available

Guidance sourceRecommended by consensus panels and guideline groups (Vitamin B12 Consensus Panel, ASMBS, ACG/BCS)

inv-42: holotranscobalamin — holotranscobalamin

Termholotranscobalamin

NoteMetabolically active (active B12); sensitivity similar to total cobalamin; specificity uncertain

AvailabilityClinical availability currently limited per multiple sources

inv-43: methylmalonic acid — methylmalonic acid

Termmethylmalonic acid

NoteUseful second-line plasma test to clarify functional B12 deficiency; high sensitivity for overt deficiency (>95% reported)

Clinical useRecommended when serum B12 is indeterminate or for monitoring if available

OpenPayer

Vitamin B12 and Methylmalonic Acid Testing

Coverage Criteria for Vitamin B12 and Related Tests

Covered Indications and Clinical Scenarios

Tests and Uses Not Covered

Frequency Limits and Monitoring Intervals

Provider Actions, Documentation, and Billing Notes

Ordering Requirements and Responsible Providers

Procedure Codes and Coding Notes

Background and Rationale

Definitions and Test Descriptions

Revision History

82607	Cyanocobalamin (Vitamin B-12)
83090	Homocysteine
83921	Organic acid, single, quantitative
84999	Unlisted chemistry procedure