What is ICD-10 code E72.51?

E72.51 is the ICD-10-CM diagnosis code for Non-ketotic hyperglycinemia. A rare genetic disorder where the body cannot properly break down the amino acid glycine, leading to abnormally high glycine levels in the blood and urine without ketones present. E72.51 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. E72.51 is part of the FY2026 ICD-10-CM code set published by the CMS National Center for Health Statistics and used on Medicare, Medicaid, and commercial claims in the United States.

Yes. E72.51 is a billable ICD-10-CM code that can be reported on professional and institutional claims as a primary or secondary diagnosis when the provider documentation supports the specific condition described. Billable codes in ICD-10-CM are coded to the highest level of specificity available for the documented diagnosis. E72.51 is current for fiscal year 2026 and remains in the active CMS ICD-10-CM code set published by the National Center for Health Statistics.

Which HCC does E72.51 map to under V28?

E72.51 has no payable CMS-HCC V28 mapping in the final FY2026 CMS file.

What RAF reference is published for E72.51?

E72.51 has no V28 reference coefficient because the final FY2026 source verifies no payable V28 mapping.

What is the V28 vs V24 difference for E72.51?

E72.51 has verified no payable V28 mapping in the final FY2026 source. Select a historical effective period before making any V24 comparison.

What documentation supports E72.51?

This is a specific metabolic disorder requiring documentation of the non-ketotic presentation to distinguish from other glycine metabolism disorders Verify genetic testing results are documented to support diagnosis, as this is an inherited condition E72.51 is not a CMS-HCC V28 payment code in the verified current source, so MEAT is not the payment hook. Documentation still has to support the diagnosis if you report it.

Can E72.51 be a primary diagnosis?

Yes. E72.51 carries no code-first instruction in the FY2026 tabular, so it can be the first-listed diagnosis when it is the condition chiefly responsible for the encounter and the note supports it, and it can also be reported as a secondary diagnosis. For risk adjustment the order does not matter; the V28 category is the same either way.

Which codes cannot be reported with E72.51?

The Excludes1 note that applies to E72.51 lists transitory endocrine and metabolic disorders specific to newborn (P70-P74); androgen insensitivity syndrome (E34.5-); congenital adrenal hyperplasia (E25.0); hemolytic anemias attributable to enzyme disorders (D55.-); and 7 more (see the notes on this page). An Excludes1 condition is not reported together with E72.51; report one or the other, unless the two conditions are unrelated, which the ICD-10-CM Official Guidelines (Section I.A.12.a) allow. The Excludes2 note lists Ehlers-Danlos syndromes (Q79.6-); those are separate conditions that may be reported together with E72.51 when both are documented.

2026 ICD-10-CM E72.51: Non-ketotic hyperglycinemia

E72.51 is not a CMS-HCC payment code. MEAT criteria · RAF Calculator · HCC coding software

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Code lookupE72.51

Effective periodFY2026 Apr Update (Apr 1-Sep 30)

FY 2026 Apr update / Endocrine, nutritional and metabolic diseases (E00-E89) / Metabolic disorders (E70-E88)

E72.51

Billable / SpecificICD-10-CMOfficial ICD-10-CMCodebook guidance

Non-ketotic hyperglycinemia

A rare genetic disorder where the body cannot properly break down the amino acid glycine, leading to abnormally high glycine levels in the blood and urine without ketones present.

Buddy Insight

Overview Risk Models Code Book Documentation Audit Notes Edition comparison

CMS-HCC V28

N/A

—

Not risk-adjusted for this model/period.

Not mapped

CMS-HCC V24

Historical

Not used for standard CY2026 Medicare Advantage payment. Select a historical period to review V24.

Not used for CY2026 payment

ACA/HHS

Context needed

HCC 028

Conditional HHS-HCC mapping: HCC 028 when age < 21. Select the member context before showing a coefficient reference. Metal level and model segment are required for coefficients; no single RAF is shown.

Coefficient needs member context

ESRD/PACE

Context needed

HCC 23

ESRD candidates: HCC 23 when age < 21 or age >= 21. ESRD mapping is separate from PACE. Dialysis, graft, age, and other member context determine the applicable coefficient.

Coefficient needs member context

RXHCC

Mapped

HCC 43

Pituitary, Adrenal Gland, and...

Code-level coefficient reference

Code Book Path

Official

E72Other disorders of amino-acid metabolism E72.5Disorders of glycine metabolism E72.51Non-ketotic hyperglycinemia

Inclusion Terms

Official

No inclusion terms are included in this display for E72.51. Check the code and parent instructions in the Code Book.

Excludes 2

Official

Ehlers-Danlos syndromes (Q79.6-)Inherited from E70-E88

Related Codes

Official

E72.50Disorder of glycine metabolism, unspecified E72.52Trimethylaminuria E72.53Primary hyperoxaluria E72.54Secondary hyperoxaluria E72.59Other disorders of glycine metabolism

Includes

Official

No Includes notes are included in this display for E72.51. Check the code and parent instructions in the Code Book.

Excludes 1

Official

transitory endocrine and metabolic disorders specific to newborn (P70-P74)Inherited from E00-E89, E70-E88, E72
androgen insensitivity syndrome (E34.5-)Inherited from E00-E89, E70-E88, E72
congenital adrenal hyperplasia (E25.0)Inherited from E00-E89, E70-E88, E72
hemolytic anemias attributable to enzyme disorders (D55.-)Inherited from E00-E89, E70-E88, E72
Marfan syndrome (Q87.4-)Inherited from E00-E89, E70-E88, E72
5-alpha-reductase deficiency (E29.1)Inherited from E00-E89, E70-E88, E72
disorders of:Inherited from E00-E89, E70-E88, E72
aromatic amino-acid metabolism (E70.-)Inherited from E00-E89, E70-E88, E72
branched-chain amino-acid metabolism (E71.0-E71.2)Inherited from E00-E89, E70-E88, E72
fatty-acid metabolism (E71.3)Inherited from E00-E89, E70-E88, E72
purine and pyrimidine metabolism (E79.-)Inherited from E00-E89, E70-E88, E72
gout (M1A.-, M10.-)Inherited from E00-E89, E70-E88, E72

Code First

Official

No Code First sequencing instructions are included in this display for E72.51. Check the code and parent instructions in the Code Book.

Use Additional

Official

No Use Additional Code instructions are included in this display for E72.51. Check the code and parent instructions in the Code Book.

Code Also

Official

No Code Also instructions are included in this display for E72.51. Check the code and parent instructions in the Code Book.

Buddy Documentation Tip

HCC Buddy guidance

Confirmed diagnosis of non-ketotic hyperglycinemia (glycine encephalopathy)

Elevated cerebrospinal fluid-to-plasma glycine ratio confirming the diagnosis

Genetic testing results identifying mutations in glycine cleavage system genes (GLDC, AMT, GCSH)

Documentation of clinical form: neonatal, infantile, or late-onset/attenuated

MEAT Support

HCC Buddy guidance

Confirmed diagnosis of non-ketotic hyperglycinemia (glycine encephalopathy)

Elevated cerebrospinal fluid-to-plasma glycine ratio confirming the diagnosis

Genetic testing results identifying mutations in glycine cleavage system genes (GLDC, AMT, GCSH)

Documentation of clinical form: neonatal, infantile, or late-onset/attenuated

Audit Caution

HCC Buddy guidance

Coding only the seizure disorder without the underlying metabolic diagnosis

Confusing non-ketotic hyperglycinemia with ketotic hyperglycinemia (which is actually organic acidemia)

Using the unspecified glycine metabolism code (E72.50) when NKH has been confirmed

Failing to code the neurological manifestations (seizures, developmental delay) as additional diagnoses

Common Mistakes

HCC Buddy guidance

E72.50 — Disorder of glycine metabolism, unspecified: use only when the specific type is not documented

E72.59 — Other disorders of glycine metabolism: for glycine disorders other than NKH

E72.52 — Trimethylaminuria: different metabolic pathway, not a glycine cleavage defect

G40.89 — Other seizures: seizures are a manifestation of NKH, not the primary diagnosis

Current with CMS: FY2026 ICD-10-CM Apr 1 update (effective Apr 1 – Sep 30, 2026) · CMS-HCC V28, 100% phased in for payment year 2026. FY2027 code set already staged for October 1, 2026. How HCC Buddy stays current →

Is E72.51 an HCC code?

E72.51 is not in the CMS-HCC V28 or V24 community payment model. E72.51 has a separate mapping under the CMS-HCC ESRD model (HCC 23 (Other Significant Endocrine and Metabolic Disorders)) and the Part D RxHCC model (HCC 43 (Pituitary, Adrenal Gland, and Other Endocrine and Metabolic Disorders)); the applicable result needs member context. E72.51 also appears in the HHS-HCC commercial risk model (HCC 028 (HHS-HCC 028 child, RAF varies by metal level)), where the result depends on member context and is not a Medicare Advantage payment mapping.

Code: E72.51
Description: Non-ketotic hyperglycinemia
HCC (V28): No CMS-HCC V28 mapping
RAF reference coefficient: —
Billable: Yes
Payment year: 2026

HCC Category Mapping

RxHCCHCC 43, Pituitary, Adrenal Gland, and Other Endocrine and Metabolic Disorders

Not separately weighted

These are source-labeled model coefficients, not member totals. A category may still be removed by hierarchy or model cleanup rules. Weights are not directly comparable across models: CMS-HCC V28 and V24 use Community, Non-Dual, Aged; ESRD uses the dialysis continuing-enrollee model; RxHCC is the Part D continuing-enrollee, non-low-income, aged weight (a larger scale than CMS-HCC). ACA/HHS has no single weight — it varies by metal level. Actual per-patient RAF contribution depends on member context, hierarchy and cleanup rules, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains available for historical review.

Work E72.51 in the Code Book — tabular path, V28 RAF reference, and MEAT checklist →

MEAT review for E72.51

For E72.51, confirm that the documentation supports the diagnosis and meets the applicable coding, encounter, program and payer requirements. MEAT (Monitor, Evaluate, Assess, or Treat) is a review mnemonic, not a universal CMS coding rule.

MMonitor: signs, symptoms, disease progression, or lab trending documented in the note
EEvaluate: test results, medication response, or physical findings reviewed by the provider
AAssess: explicit mention in the assessment or plan with acknowledgment of status
TTreat: medication, referral, procedure, therapy, or counseling tied to the diagnosis

Coder workflow notes

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What This Code Means

E72.51 is the ICD-10-CM diagnosis code for non-ketotic hyperglycinemia. A rare genetic disorder where the body cannot properly break down the amino acid glycine, leading to abnormally high glycine levels in the blood and urine without ketones present. E72.51 sits in the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89), within the section covering metabolic disorders (e70-e88).

E72.51 has no mapping under the CMS-HCC V28 or V24 community payment models. E72.51 has a separate mapping under the CMS-HCC ESRD model (HCC 23 (Other Significant Endocrine and Metabolic Disorders)) and the Part D RxHCC model (HCC 43 (Pituitary, Adrenal Gland, and Other Endocrine and Metabolic Disorders)); the applicable result needs member context. E72.51 also appears in the HHS-HCC commercial risk model (HCC 028 (HHS-HCC 028 child, RAF varies by metal level)), where the result depends on member context and is not a Medicare Advantage payment mapping. Do not assign V28 risk adjustment value from this page; verify the applicable model and payment year before using this code for risk adjustment.

This is a specific metabolic disorder requiring documentation of the non-ketotic presentation to distinguish from other glycine metabolism disorders.

HCC Buddy maintains structured V28 and V24 mapping, source-labeled coefficient references, and MEAT documentation criteria for E72.51 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•This is a specific metabolic disorder requiring documentation of the non-ketotic presentation to distinguish from other glycine metabolism disorders
•Verify genetic testing results are documented to support diagnosis, as this is an inherited condition

Clinical Significance

Non-ketotic hyperglycinemia is a severe inborn error of glycine metabolism caused by defects in the glycine cleavage system, leading to toxic accumulation of glycine in the brain and cerebrospinal fluid. This condition causes intractable seizures, profound intellectual disability, and high early mortality. Accurate coding is essential as these patients require intensive, lifelong multidisciplinary care.

Documentation Requirements

✓Confirmed diagnosis of non-ketotic hyperglycinemia (glycine encephalopathy)
✓Elevated cerebrospinal fluid-to-plasma glycine ratio confirming the diagnosis
✓Genetic testing results identifying mutations in glycine cleavage system genes (GLDC, AMT, GCSH)
✓Documentation of clinical form: neonatal, infantile, or late-onset/attenuated
✓Current treatment including sodium benzoate, dextromethorphan, or anti-seizure medications

Commonly Confused Codes

•E72.50: Disorder of glycine metabolism, unspecified: use only when the specific type is not documented
•E72.59: Other disorders of glycine metabolism: for glycine disorders other than NKH
•E72.52: Trimethylaminuria: different metabolic pathway, not a glycine cleavage defect
•G40.89: Other seizures: seizures are a manifestation of NKH, not the primary diagnosis