CurrentCapital BluecrossPolicy AHS G2056

Diagnosis of Idiopathic Environmental Intolerance

Defines coverage stance for laboratory and diagnostic testing related to idiopathic environmental intolerance (IEI)/multiple chemical sensitivity, including explicit noncoverage of many lab panels and breath tests and reimbursement unit limits for specific CPT codes. Applies based on member benefits and federal/state regulations.

Policy Summary

PayerCapital Bluecross

PolicyDiagnosis of Idiopathic Environmental Intolerance

Policy CodePolicy AHS G2056

Change TypeNo material change

Effective DateSep 18, 2015

Next Review Date

Key ActionDetermine coverage based on the individual's benefit coverage and applicable Medicare/Medicaid/local coverage determinations; if conflict exists, follow government policy.

SourceLink

Trek Health ingests and normalizes Transparency in Coverage data and payer policy updates to give provider organizations a clear view of how commercial reimbursement behaves across markets, payers, and services. Our platform transforms raw payer disclosures into structured intelligence that supports contract evaluation, payer negotiations, and service line strategy. By combining market benchmarks with ongoing policy visibility, Trek helps teams identify variability, risk, and opportunity in commercial reimbursement. The result is faster insight, stronger negotiating positions, and more informed financial decisions.

Coverage Summary

Policy AHS G2056 (Diagnosis of Idiopathic Environmental Intolerance) is CURRENT (effective 2015-09-18, last reviewed 2025-04-01) and addresses laboratory and diagnostic testing related to idiopathic environmental intolerance (IEI, formerly multiple chemical sensitivity). The policy defines many such tests — including numerous laboratory panels and breath tests — as not meeting coverage criteria and notes that reimbursement unit limits apply for certain CPT codes. Coverage determinations depend on the member's benefit plan and applicable Medicare/Medicaid or other government policies.

Key facts

Policy numberAHS G2056

SubjectDiagnosis of Idiopathic Environmental Intolerance (IEI) testing

Effective date2015-09-18

Last review2025-04-01

Coverage stanceNot Covered

Explicit not-covered categories listed (stats)9

CPT codes referenced (stats)10+

CPT codes with unit limits specified (stats)9

References Listed (stats)Literature citations

Not Meeting Coverage Criteria

Application and Limitations

Coding

Procedure codes referenced in policy (informational)CPT

82108	Aluminum
82127	Amino acids; single, qualitative, each specimen
82136	Amino acids, 2 to 5 amino acids, quantitative, each specimen
82139	Amino acids, 6 or more amino acids, quantitative, each specimen
82300	Cadmium
82379	Carnitine (total and free) quantitative each specimen
82380	Carotene
82441	Chlorinated hydrocarbons, screen
82495	Chromium
82507	Citrate

1–10 of 41

1/5

Codes with unit limits (reimbursement rules)CPT

83919	Organic acids; qualitative, each specimen - maximum 1 unit per date of service
83921	Organic acid, single, quantitative - maximum 2 units per date of service
82127	Amino acids; single, qualitative, each specimen - maximum 1 unit per date of service
82136	Amino acids, 2 to 5 amino acids, quantitative, each specimen - maximum 2 units per date of service
82139	Amino acids, 6 or more amino acids, quantitative, each specimen - maximum 2 units per date of service
84585	Vanillylmandelic acid (VMA) urine - maximum 1 unit per date of service
83150	Homovanillic acid (HVA) - maximum 1 unit per date of service
83497	Hydroxyindolacetic acid (5-HIAA) - maximum 1 unit per date of service
82656	Elastase, pancreatic (EL-1) fecal; qualitative or semi-quantitative - maximum 1 unit per date of service

Procedure codes listed in this policy are provided for informational purposes. When submitting claims, providers must follow the stated reimbursement rules and apply the listed maximum allowed units per date of service for CPT codes in the second code group (for example, 83919=1 unit; 83921=2 units; 82127=1 unit; 82136 & 82139=2 units; 84585=1 unit; 83150=1 unit; 83497=1 unit; 82656=1 unit).

Provider Actions

Documentation Required

Verify member benefits and applicable government coverage

Determine coverage using the member's specific benefit plan and any applicable Medicare/Medicaid local or national coverage determinations. When there is a conflict between this policy and a government coverage determination (LCD, NCD, or state Medicaid), follow the government policy. Note that LDTs are regulated under CLIA '88 and lack FDA approval, but FDA status does not alter coverage determinations.

Follow government policy when conflict exists

Denial Risk

Claims for tests to diagnose IEI are deniable

Claims for laboratory tests ordered to confirm a diagnosis of idiopathic environmental intolerance (IEI) and for specified profiling/screening tests should be expected to be denied as not meeting coverage criteria.

Examples of affected codes: 82441 (Chlorinated hydrocarbons, screen), 83918 (Organic acids; total, quantitative), 91065 (Breath hydrogen or methane test)

Background and Evidence

IEI (formerly multiple chemical sensitivity) is described as a subjective condition with recurrent, nonspecific symptoms attributed to low-level exposures and without consistent physical findings or laboratory abnormalities. The evidence base for specific diagnostic testing is weak, and professional societies have expressed skepticism or discouraged such testing. Laboratory-developed tests (LDTs) used for some of these assays are regulated under CLIA '88 as high-complexity tests and are not FDA-approved/cleared.

Evidence	Summary / Sources
Professional society positions	Multiple societies (AAAAI, ACOEM, ACP and others) express skepticism or discourage testing for IEI; position statements note lack of consistent physical findings or lab abnormalities (AAAAI 1999/2006; ACOEM 1999; ACP) and recommend avoiding unnecessary testing.
Breath test performance	Breath tests for SIBO/lactose have variable sensitivity and specificity and methodological limitations (transit time, substrate, false positives/negatives); reviews and studies note low sensitivity/specificity and poor correlation with small bowel culture (Rezaie 2017; Rangan 2022; Bushyhead & Quigley 2022; Pimentel 2024).
Key guideline sources	Guidelines include North American Consensus on Breath Testing (Rezaie et al. 2017), ACG Clinical Guideline on SIBO (Pimentel et al. 2020), and statements by AAAAI/ACOEM/ACP addressing IEI testing limitations and approaches.
Recent reviews	Recent authoritative reviews and summaries: UptoDate and Merck Manual entries on IEI (Black & Temple, 2024), systematic reviews highlighting methodological limitations in IEI/EHS studies (Schmiedchen et al. 2019), and multiple reviews on breath testing utility (Usai-Satta 2021; Rangan 2022).

Definitions

IEI: Idiopathic environmental intolerance (formerly multiple chemical sensitivity) — a subjective condition characterized by nonspecific symptoms attributed to low-level exposures without consistent physical findings or laboratory abnormalities.

LDT: Laboratory-developed test regulated under CLIA '88 as a high-complexity test; these tests are performed in-house by laboratories and are not approved or cleared by the FDA.

Unit Limits / Thresholds

Per-date unit limits

83919maximum 1 unit per date of service

83921maximum 2 units per date of service

82127maximum 1 unit per date of service

82136maximum 2 units per date of service

82139maximum 2 units per date of service

84585maximum 1 unit per date of service

83150maximum 1 unit per date of service

83497

Revision History

2015-09-18effective

Policy effective

2025-04-01reviewLatest

Most recent review