Currentblue cross blue shield - louisianaPolicy AHS - G2164 - Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing

G2164: Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing

Defines medical coverage criteria and limitations for serum and urine testing of intact parathyroid hormone (PTH), calcium (total and ionized), phosphorus/phosphate, and magnesium, including indications, frequencies for monitoring in specific conditions, and tests considered not medically necessary.

Policy Summary

Payerblue cross blue shield - louisiana

PolicyG2164: Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing

Policy CodePolicy AHS - G2164 - Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing

Change TypeRevised (consolidated PTH criteria)

Effective DateSep 1, 2025

Next Review DateN/A

Key ActionWhen ordering PTH testing, document the clinical indication consistent with the covered indications (e.g., abnormal calcium, osteoporosis, post-parathyroidectomy, CKD grade, MEN2A, pseudohypoparathyroidism) to support medical necessity.

SourceLink

POLICY UPDATE CHANGES

09/01/2025: Background, guidelines, recommendations and references updated; CC1 and CC2 were wrapped into a single consolidated PTH testing criterion with enumerated indications and frequencies.

10/01/2024: Literature review did not necessitate modifications to coverage criteria.

06/01/2023 and 01/01/2023: Literature reviews / edits for clarity; 01/01/2023 added wording change to CC1a to specify assessment for possible hyperparathyroidism in patients with hypercalcemia.

05/15/2022: Initial Policy Implementation.

8Enumerated covered PTH indications

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6Wellness visit tests not covered

1Not covered: truncated PTH metabolites

7Applicable CPT codes listed

yesCKD monitoring intervals enumerated

Coverage Summary

Policy AHS - G2164 - Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing defines medical coverage for serum and urine testing of intact parathyroid hormone (PTH), total and ionized calcium, phosphorus/phosphate, and magnesium. The policy is effective and last reviewed on 09/01/2025. Coverage stance is mixed: specific clinical indications and monitoring frequencies are enumerated and considered medically necessary, while routine screening (for asymptomatic hyperparathyroidism) and a set of wellness-visit tests are explicitly not covered.

Medical-Necessity Criteria

Not Medically Necessary / Exclusions

Coding

Applicable Procedure CodesCPT

82310	Calcium; total
82330	Calcium; ionized
82340	Calcium; urine quantitative, timed specimen
83735	Magnesium
83970	Parathormone (parathyroid hormone)
84100	Phosphorus inorganic (phosphate)
84105	Phosphorus inorganic (phosphate); urine

Applicable CPT/HCPCS procedure codesmixed

No codes listed

No specific billing codes present in this excerptmixed

No codes listed

No codes listed in this partmixed

No codes listed

Provider Actions & Billing Guidance

Documentation Required

Document clinical indication for PTH testing

Document the clinical indication for PTH testing in the medical record at the time of order. Clear documentation supports medical necessity for coverage and should reference specific signs, conditions, or monitoring reasons.

Abnormal serum calcium (total or ionized)
One-time diagnostic evaluation for suspected hypoparathyroidism (document signs such as hypocalcemia, elevated serum phosphorus, low calcitriol, hypercalciuria, or abnormal magnesium)
Evaluation of osteoporosis or low bone mass (for secondary causes)
Pre- or post-parathyroidectomy assessment
Annual monitoring for diagnosed primary hyperparathyroidism (if no parathyroidectomy)
CKD monitoring per stage-specific intervals (see CKD monitoring callout)
Suspected multiple endocrine neoplasia (e.g., MEN2A) or familial medullary thyroid carcinoma (one-time)
Suspected pseudohypoparathyroidism or related disorders (document diagnosis and age for frequency determination)
Suspected genetic primary hyperparathyroidism (document rationale and refer for genetic testing when appropriate)
Monitoring during therapies that affect calcium/PTH axis (e.g., denosumab, bisphosphonates, or agents associated with tumor lysis syndrome)

Background & Evidence

PTH is an 84‑amino‑acid peptide that regulates calcium and phosphate homeostasis by increasing bone resorption, renal calcium reabsorption and modulating phosphate via effects on FGF23 and vitamin D; magnesium also modulates PTH secretion. Assays for intact PTH are affected by short PTH half‑life and abundant truncated fragments, producing substantial method‑related variation (up to ~4–5‑fold between methods). Preanalytical handling affects stability: addition of EDTA to blood tubes improves plasma stability (recommended sampling ideally between 10:00 and 16:00, plasma separated within 24 hours, and plasma analyzed within 72 hours), and serum is less stable than EDTA plasma. Clinical guideline contexts for testing include evaluation and monitoring of primary and secondary hyperparathyroidism, CKD and CKD‑MBD, hypoparathyroidism (diagnosis requires hypocalcemia with low/inappropriately normal PTH on two occasions), pseudohypoparathyroidism, perioperative/parathyroidectomy assessment, osteoporosis evaluation, and disease‑specific monitoring per specialty guidance.

Source	Key Finding
IFCC findings	PTH assays show method-related variation up to five-fold; EDTA stabilizes plasma samples; recommended sampling between 10:00 and 16:00 and plasma separation within 24 hours.
AAES 2016 recommendation	Biochemical evaluation of suspected primary hyperparathyroidism should include serum total calcium, PTH, creatinine, and 25-hydroxyvitamin D; consider 24-hour urine calcium and creatinine; intraoperative PTH monitoring recommended for focused parathyroidectomy.
KDIGO (2012/2017/2024)	Recommend measuring calcium, phosphate, PTH and alkaline phosphatase beginning in CKD G3a (baseline if GFR <45 ml/min/1.73 m2) with monitoring intervals by GFR category (G3a-G3b every 6–12 months; G4 every 3–6 months; G5 every 1–3 months for calcium/phosphate; PTH frequency varies by stage).
NCCN	Multiple disease-specific recommendations to measure calcium and related labs for diagnosis, surveillance and therapy safety (e.g., annual calcium and PTH surveillance for MEN syndromes; TLS and denosumab monitoring requirements).
International Workshop on PHPT	Recommends annual serum calcium testing for asymptomatic PHPT, use corrected calcium formula, comprehensive biochemistry panel, DXA BMD, vertebral assessment, 24-hour urine calcium and fractional excretion of calcium, and selection of bone turnover markers (P1NP, CTX, NTX) as indicated.
KDOQI timeline	Provides frequency tables for PTH and calcium/phosphorus by CKD stage and post-transplant periods (e.g., CKD G3: PTH every 12 months; G4: PTH every 3 months; post-transplant monitoring schedule in Table 33).
Guideline citations (NCCN, KDIGO, NICE, AACE/ACE, ATA, others)	Multiple guideline sources cited across the policy to support testing indications and monitoring intervals for PTH, calcium, phosphorus and magnesium in varied clinical contexts.
Evidence references (selected)	Key supporting studies and reviews referenced include systematic IFCC review of PTH sampling/stability, LIAISON 1-84 assay validation, and guideline publications underpinning recommendations.
IFCC analytical priorities	Method-related between-assay differences can be >4-fold affecting clinical decisions; within-lab CVs <10% but between-method CVs >20%; standardized approaches and assay-generation selection advised.

Definitions

Term	Definition
PTH	Parathyroid hormone; intact PTH assayed for clinical evaluation.
CKD	Chronic kidney disease; grading (G1-G5 and transplant suffix T) referenced for monitoring frequency.
Pseudohypoparathyroidism (PHP)	Group of disorders with PTH resistance often due to GNAS or related mutations; monitoring frequency differs by age.
Corrected calcium	Estimated serum calcium adjusted for albumin using: total serum calcium (mg/dL) + 0.8*(4.0 - serum albumin (g/dL)). Recommended for monitoring in most centers.
PTH assay generation	Recommendation specifies use of second- or third-generation immunoassays for parathyroid hormone measurement.
P1NP	Procollagen type 1 N-propeptide (bone formation marker), recommended as a selectable bone turnover marker in PHPT evaluation.
CTX	C-telopeptide cross-linked collagen type I (bone resorption marker), recommended as a selectable bone turnover marker in PHPT evaluation.
NTX	N-telopeptide of type I collagen (urinary resorption marker), recommended as a selectable bone turnover marker in PHPT evaluation.
TBS	Trabecular Bone Score by DXA; optional/recommended where available for assessment in PHPT evaluation/monitoring.
ACR	Albumin-to-creatinine ratio; used to confirm albuminuria with threshold ≥30 mg/g (≥3 mg/mmol) per KDIGO recommendations.
GFR categories (G1-G5, GxT)	CKD staging referenced in KDIGO/KDOQI; transplant suffix 'T' denotes post-transplant kidney function categories used to determine testing intervals.
Note 1 - Signs of hypoparathyroidism	Hypocalcemia; Elevated serum phosphorus; Low calcitriol; Hypercalciuria; Abnormal magnesium — these signs justify one-time diagnostic PTH testing per coverage criteria.

Guideline-based Monitoring Recommendations

The policy’s specified testing frequencies and covered indications align with cited guideline recommendations: KDIGO/KDOQI guidance and tables inform CKD and transplant monitoring intervals (e.g., annual for CKD G3, quarterly for advanced CKD), the International Workshop on PHPT supports annual calcium and PTH evaluation and the listed PHPT assessment components, and pseudohypoparathyroidism consensus statements recommend age‑dependent monitoring intervals. Where guidelines prescribe condition‑specific timing or testing (NICE, AAES, ASBMR, NCCN, ESE, etc.), the policy adopts those intervals and indications when specified.

Revision History

2025-09-01material revisionLatest

Background, guidelines, recommendations and references updated; CC1 and CC2 consolidated into a single PTH testing criterion enumerating indications (abnormal calcium, one-time hypoparathyroidism diagnosis with Note 1 signs, osteoporosis/low bone mass, post-parathyroidectomy, annual monitoring for hyperparathyroidism without parathyroidectomy, CKD grade–based frequencies, one-time MEN2A/familial medullary thyroid carcinoma testing, and age-based frequencies for pseudohypoparathyroidism) and Note 1 added defining signs of hypoparathyroidism.

2024-10-01clarified

Literature review did not necessitate modifications to coverage criteria.

Policy Summary

Payerblue cross blue shield - louisiana

PolicyG2164: Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing

Policy CodePolicy AHS - G2164 - Parathyroid Hormone, Phosphorus, Calcium, and Magnesium Testing

Change TypeRevised (consolidated PTH criteria)

Effective DateSep 1, 2025

Next Review DateN/A

SourceLink

On This Page

Denial Risk

Do not order PTH for asymptomatic hyperparathyroidism screening

Do not order intact PTH to screen asymptomatic individuals for primary hyperparathyroidism. Claims for PTH ordered solely for asymptomatic population screening may be denied.

Screening asymptomatic hyperparathyroidism without abnormal calcium or other clinical indication = not medically necessary

Billing Rule

Do not order truncated PTH metabolite assays

Truncated PTH metabolite assays (amino‑terminal, carboxy‑terminal fragments) are not supported by evidence for clinical decision-making in routine care and do not meet coverage criteria.

Do not order assays for PTH fragments (e.g., amino‑terminal or carboxy‑terminal) — testing is not covered

Documentation Required

Use corrected calcium for monitoring

When monitoring calcium in patients being evaluated for or treated for parathyroid disorders, calculate and document corrected (albumin‑adjusted) calcium when total calcium is used. Use the corrected value for clinical decisions if ionized calcium is not available.

Corrected calcium (mg/dL) = measured total calcium (mg/dL) + 0.8 × (4.0 − serum albumin [g/dL])

Documentation Required

Annual serum calcium testing

For individuals with diagnosed primary hyperparathyroidism who are managed without parathyroidectomy, document annual serum calcium testing to monitor disease progression and the need for surgical referral.

At least one serum calcium measurement every 12 months for non-operated primary hyperparathyroidism

Documentation Required

Comprehensive evaluation components

Document the components of a comprehensive evaluation when assessing hyperparathyroidism or related mineral metabolism disorders. Recording these elements supports appropriate testing and follow-up.

Basic biochemistry panel including serum calcium (total and/or ionized), phosphorus, creatinine, and electrolytes
25‑hydroxyvitamin D [25(OH)D] level
Specify PTH assay generation (second‑ or third‑generation intact PTH) in the record when relevant
DXA bone mineral density with documented sites evaluated (spine, hip, and forearm as indicated)
24‑hour urine calcium collection when differentiating familial hypocalciuric hypercalcemia from primary hyperparathyroidism
Bone turnover markers when indicated (see note: select markers such as serum C‑telopeptide [CTX] or PINP depending on clinical context)
Fractional excretion measurements or urine studies to evaluate renal calcium handling
Genetic testing referral/documentation if genetic PHPT is suspected (e.g., MEN syndromes, familial isolated hyperparathyroidism)

Documentation Required

CKD monitoring intervals

Follow guideline-based CKD monitoring intervals for PTH testing. Document CKD stage (eGFR) and the interval rationale in the chart.

CKD G3 (eGFR 30–59 mL/min/1.73 m2): PTH testing every 12 months
CKD G4–G5 (eGFR <30 mL/min/1.73 m2): PTH testing every 3 months
Document CKD stage and trend in eGFR to justify frequency

Billing Rule

Report CPT codes for tests performed

Report the CPT codes for each test performed on the claim form. Accurate coding ensures appropriate processing and reduces risk of denials.

82310 — Calcium; total
82330 — Phosphorus (phosphate)
82340 — Magnesium; serum
83735 — Parathyroid hormone (intact PTH)
83970 — Parathyroid hormone, related peptide (PTHrP)
84100 — Calcium; ionized
84105 — Calcium; ultrafiltrate, ionized

Prior Authorization

Follow government policy when conflict exists

When governmental policies (e.g., Medicare/Medicaid) conflict with this policy, follow the applicable government program rules for those members. Document application of government rules in the member's record when used.

Apply Medicare/Medicaid frequency or coverage exceptions when the member is covered under those programs

Documentation Required

PTH sampling and assay considerations

Follow specimen handling and assay considerations for reliable PTH measurement and document assay type and sampling conditions. Proper preanalytic technique reduces erroneous results.

Collect blood for many PTH assays in EDTA (lavender) tubes and separate plasma promptly per laboratory instructions
If using serum, follow lab‑specific handling times and temperature recommendations to avoid degradation
Specify assay generation in documentation (second‑generation/intact PTH vs third‑generation) as values are not interchangeable

Billing Rule

Adhere to specified testing frequencies

Adhere to specified testing frequencies across clinical scenarios. Document the clinical context and applicable guideline used to justify interval.

Primary hyperparathyroidism without surgery: annual PTH/calcium monitoring
CKD stage‑based monitoring: annual for G3; every 3 months for G4–G5
Pseudohypoparathyroidism: children <18 years — every 3 months; adults ≥18 years — annually
Confirm positive semi‑quantitative albuminuria/proteinuria with quantitative testing (e.g., urine albumin‑to‑creatinine ratio) before attributing mineral abnormalities to kidney disease
Monitor patients receiving denosumab or other potent antiresorptives with appropriate calcium/PTH testing per therapy-specific guidance
For patients at risk of tumor lysis syndrome (e.g., undergoing venetoclax per NCCN), monitor electrolytes and calcium/PTH per NCCN TLS recommendations

2023-06-01clarified

Literature review and policy edits for clarity; no changes to coverage criteria.

2023-01-01clarified

Wording change added to clarify CC1a phrasing to specify assessment for possible hyperparathyroidism in patients with hypercalcemia.

2022-05-15initial implementation

Initial policy implementation (original effective date).