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v1.0.0
ICD-10 Guide
ICD-10 CodesD51.2

D51.2

Billable

Transcobalamin II deficiency

BILLABLE STATUSYes
IMPLEMENTATION DATEOctober 1, 2015
LAST UPDATED09/05/2025

Code Description

ICD-10 D51.2 is a billable code used to indicate a diagnosis of transcobalamin ii deficiency.

Key Diagnostic Point:

Transcobalamin II deficiency is a rare inherited disorder characterized by the inability to transport vitamin B12 (cobalamin) in the body due to a defect in transcobalamin II, a protein responsible for the cellular uptake of vitamin B12. This deficiency leads to a functional vitamin B12 deficiency, resulting in megaloblastic anemia, neurological symptoms, and impaired DNA synthesis. Patients may present with symptoms such as fatigue, pallor, weakness, and neurological deficits including peripheral neuropathy and cognitive disturbances. Diagnosis is typically confirmed through laboratory tests showing low serum vitamin B12 levels, elevated methylmalonic acid, and homocysteine levels. Treatment involves lifelong vitamin B12 supplementation, often administered via intramuscular injections, to bypass the transport defect and ensure adequate cellular uptake. Regular monitoring of vitamin B12 levels and hematological parameters is essential to manage the condition effectively.

Code Complexity Analysis

Complexity Rating: Medium

Medium Complexity

Complexity Factors

  • Rarity of the condition leading to potential unfamiliarity among coders.
  • Need for precise documentation of laboratory results to support diagnosis.
  • Differentiation from other types of anemia, particularly megaloblastic anemia due to folate deficiency.
  • Potential for co-existing conditions that may complicate coding.

Audit Risk Factors

  • Insufficient documentation of laboratory results.
  • Failure to document the clinical rationale for B12 supplementation.
  • Inadequate differentiation from other anemia types.
  • Lack of follow-up documentation to support ongoing treatment.

Specialty Focus

Medical Specialties

Hematology

Documentation Requirements

Detailed lab results, clinical history, and treatment plans.

Common Clinical Scenarios

Diagnosis and management of megaloblastic anemia, monitoring of vitamin B12 levels.

Billing Considerations

Ensure accurate documentation of the patient's response to treatment and any neurological assessments.

Genetics

Documentation Requirements

Genetic testing results and family history.

Common Clinical Scenarios

Evaluation of hereditary conditions affecting vitamin B12 metabolism.

Billing Considerations

Documentation of genetic counseling provided to the patient and family.

Coding Guidelines

Inclusion Criteria

Use D51.2 When
  • According to ICD
  • 10 coding guidelines, D51
  • 2 should be used when there is a confirmed diagnosis of transcobalamin II deficiency with supporting laboratory evidence
  • It is important to document any associated conditions or complications

Exclusion Criteria

Do NOT use D51.2 When
No specific exclusions found.

Related ICD-10 Codes

Related CPT Codes

85025CPT Code

Complete blood count (CBC) with automated differential

Clinical Scenario

Used to evaluate anemia in patients suspected of having transcobalamin II deficiency.

Documentation Requirements

Document the reason for the CBC and any relevant clinical findings.

Specialty Considerations

Hematology specialists should ensure that all relevant lab results are included in the patient's record.

ICD-10 Impact

Diagnostic & Documentation Impact

Enhanced Specificity

ICD-10 Improvements

The transition to ICD-10 has allowed for more specific coding of transcobalamin II deficiency, improving the accuracy of data collection and reimbursement processes. This specificity aids in better understanding the prevalence and management of this rare condition.

ICD-9 vs ICD-10

The transition to ICD-10 has allowed for more specific coding of transcobalamin II deficiency, improving the accuracy of data collection and reimbursement processes. This specificity aids in better understanding the prevalence and management of this rare condition.

Reimbursement & Billing Impact

reimbursement processes. This specificity aids in better understanding the prevalence and management of this rare condition.

Resources

Clinical References

  • •
    National Institutes of Health - Transcobalamin II Deficiency

Coding & Billing References

  • •
    National Institutes of Health - Transcobalamin II Deficiency

Frequently Asked Questions

What are the symptoms of transcobalamin II deficiency?

Symptoms may include fatigue, weakness, pallor, neurological issues such as numbness or tingling, and developmental delays in children.

How is transcobalamin II deficiency diagnosed?

Diagnosis is made through laboratory tests showing low vitamin B12 levels, elevated methylmalonic acid, and homocysteine levels, along with clinical symptoms.

What is the treatment for transcobalamin II deficiency?

Treatment typically involves lifelong vitamin B12 supplementation, often administered via intramuscular injections, to ensure adequate cellular uptake.