What is ICD-10 code E75.249?

E75.249 is the ICD-10-CM diagnosis code for Niemann-Pick disease, unspecified. Niemann-Pick disease, unspecified is used when a patient has been diagnosed with Niemann-Pick disease but the specific type (A, B, C, or other) has not been determined or documented. E75.249 is a billable code, meaning it can be reported on a claim as a primary or secondary diagnosis when supported by documentation. E75.249 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. E75.249 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. E75.249 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.

What is the V28 vs V24 difference for E75.249?

CMS phased in the V28 risk adjustment model over payment years 2024 (33%), 2025 (67%), and 2026 (100%), replacing V24. V28 consolidates HCC categories, removes some lower-acuity conditions, and recalibrates RAF weights across the entire model. E75.249 was a payment HCC under V24 (Other Significant Endocrine and Metabolic Disorders) but the V28 recalibration removed it from the risk adjustment model. Both models can still appear in legacy data and in payer-specific lookback periods.

What should coders know when reporting E75.249?

This is a default code; attempt to obtain clarification on the specific type of Niemann-Pick disease from the provider Query the physician if type information becomes available during the episode of care to allow for more specific coding Because E75.249 maps to a payment HCC, the documentation must also satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's risk adjustment score.

E75.249: Niemann-Pick disease, unspecified —

ICD-10-CM Code View

HCC Buddy Code Card

Digital ICD-10 code-book layout with official code detail, always-visible risk models, Code Trumping, and Buddy coding guidance.

Code lookupE75.249Effective periodFY2026 Apr Update (Apr 1-Sep 30)

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

E75.249

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

Niemann-Pick disease, unspecified

Niemann-Pick disease, unspecified is used when a patient has been diagnosed with Niemann-Pick disease but the specific type (A, B, C, or other) has not been determined or documented.

Buddy Insight

Niemann-Pick disease, unspecified, is used when a patient has been diagnosed with Niemann-Pick disease but the specific type has not yet been determined through enzyme assays or genetic testing.

CMS-HCC V28

Not risk-adjusted for this model/period.

RAF 0

CMS-HCC V24

Mapped

HCC 23

Other Significant Endocrine a...

RAF 0.230

ACA/HHS

Not risk-adjusted for this model/period.

RAF 0

ESRD/PACE

Mapped

HCC 23

Other Significant Endocrine a...

RAF 0.0

RXHCC

Mapped

HCC 41

Lysosomal Storage Disorders

RAF 0.0

Code Trumping

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Code Book Path

Official

E75.2Other sphingolipidosis

E75.24Niemann-Pick disease

E75.249Niemann-Pick disease, unspecified

Inclusion Terms

Official

Acid sphingomyelinase deficiency (ASMD) NOS

Excludes 2

Official

ICD-10-CM does not list Excludes 2 notes for E75.249 in this effective period.

Related Child Codes

Official

E75.240Niemann-Pick disease type A

E75.241Niemann-Pick disease type B

E75.242Niemann-Pick disease type C

E75.243Niemann-Pick disease type D

E75.244Niemann-Pick disease type A/B

Includes

Official

ICD-10-CM does not list Includes notes for E75.249 in this effective period.

Excludes 1

Official

ICD-10-CM does not list Excludes 1 notes for E75.249 in this effective period.

Code First

Official

ICD-10-CM does not list Code First sequencing instructions for E75.249 in this effective period.

Use Additional

Official

ICD-10-CM does not list Use Additional Code instructions for E75.249 in this effective period.

Code Also

Official

ICD-10-CM does not list Code Also instructions for E75.249 in this effective period.

Buddy Documentation Tip

HCC Buddy guidance

Provider diagnosis of Niemann-Pick disease

Clinical findings supporting the diagnosis (hepatosplenomegaly, neurological symptoms)

Documentation of pending or planned enzyme assays and genetic testing

Reason the specific type is not yet known

MEAT Support

HCC Buddy guidance

Provider diagnosis of Niemann-Pick disease

Clinical findings supporting the diagnosis (hepatosplenomegaly, neurological symptoms)

Documentation of pending or planned enzyme assays and genetic testing

Reason the specific type is not yet known

Audit Caution

HCC Buddy guidance

Continuing to use this unspecified code after the specific type has been determined through testing

Not querying the provider for enzyme assay or genetic testing results that may be available

Confusing the Niemann-Pick disease name with other lysosomal storage disorders

Using this code for patients who actually have Gaucher disease or other sphingolipidoses

Common Mistakes

HCC Buddy guidance

E75.240-E75.244 — Specific Niemann-Pick types: use the appropriate code once the type is confirmed

E75.248 — Other Niemann-Pick disease: for confirmed atypical presentations, not pending workup

E75.22 — Gaucher disease: also causes hepatosplenomegaly but different enzyme

E75.10 — Unspecified gangliosidosis: broader category, not specific to Niemann-Pick

Last updated: FY2026 ICD-10-CM Apr update, Apr 1, 2026 through Sep 30, 2026. CMS-HCC V28 is 100% phased in for payment year 2026.

Is E75.249 an HCC code?

Yes. E75.249 maps to Other Significant Endocrine and Metabolic Disorders under the V24 model but is not retained in V28.

HCC Category Mapping

V24HCC 23, Other Significant Endocrine and Metabolic Disorders

0.230

ESRDHCC 23, Other Significant Endocrine and Metabolic Disorders

0.000

RxHCCHCC 41, Lysosomal Storage Disorders

0.000

RAF weights shown are the community, non-dual, aged base weights from the CMS risk adjustment model file. Actual per-patient RAF contribution depends on member segment, interactions, and the model year used by the payer. V28 is the CMS-HCC model phased in over payment years 2024–2026; V24 remains in use during the transition and for historical data.

MEAT Criteria for E75.249

For E75.249to count as a valid HCC diagnosis in a given encounter, the provider's documentation must show MEAT: Monitor, Evaluate, Assess, or Treat. A diagnosis from a prior year does not carry forward automatically, it has to be re-documented and supported each calendar year.

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

Only one of M/E/A/T is required to support the code, but the documentation must be specific enough to show that the provider actually addressed E75.249 during that encounter, not just copy-forwarded from a problem list.

What This Code Means

E75.249 is the ICD-10-CM diagnosis code for niemann-pick disease, unspecified. Niemann-Pick disease, unspecified is used when a patient has been diagnosed with Niemann-Pick disease but the specific type (A, B, C, or other) has not been determined or documented. E75.249 sits in the ICD-10-CM chapter for endocrine, nutritional and metabolic diseases (e00-e89), within the section covering metabolic disorders (e70-e88).

Under the older CMS-HCC V24 model, E75.249 maps to Other Significant Endocrine and Metabolic Disorders (HCC 23) with a community, non-dual, aged base RAF weight of 0.230. V28 is the CMS-HCC risk adjustment model that reached 100% phase-in for payment year 2026, replacing V24 which was used during the PY2024–PY2025 transition.

This is a default code; attempt to obtain clarification on the specific type of Niemann-Pick disease from the provider. Because E75.249 maps to a payment HCC, the provider's documentation must satisfy MEAT criteria (Monitor, Evaluate, Assess, or Treat) for the encounter to count toward the patient's Medicare Advantage risk adjustment score. When documentation is ambiguous, coders should issue a provider query rather than assume the highest-specificity variant.

HCC Buddy maintains structured V28 and V24 mapping, RAF weights, and MEAT documentation criteria for E75.249 sourced directly from the CMS-HCC risk adjustment model files and the CMS ICD-10-CM code set.

Coding Tips

•This is a default code; attempt to obtain clarification on the specific type of Niemann-Pick disease from the provider
•Query the physician if type information becomes available during the episode of care to allow for more specific coding

Clinical Significance

Niemann-Pick disease, unspecified, is used when a patient has been diagnosed with Niemann-Pick disease but the specific type has not yet been determined through enzyme assays or genetic testing. This code should be temporary, with efforts made to classify the type once diagnostic results are available. The specific type dramatically affects prognosis and treatment options.

Documentation Requirements

✓Provider diagnosis of Niemann-Pick disease
✓Clinical findings supporting the diagnosis (hepatosplenomegaly, neurological symptoms)
✓Documentation of pending or planned enzyme assays and genetic testing
✓Reason the specific type is not yet known
✓Current symptom management plan while awaiting definitive classification

Commonly Confused Codes

•E75.240-E75.244: Specific Niemann-Pick types: use the appropriate code once the type is confirmed
•E75.248: Other Niemann-Pick disease: for confirmed atypical presentations, not pending workup
•E75.22: Gaucher disease: also causes hepatosplenomegaly but different enzyme
•E75.10: Unspecified gangliosidosis: broader category, not specific to Niemann-Pick
•E88.9: Metabolic disorder, unspecified: too general when Niemann-Pick is diagnosed