D81.819: Biotin-dependent carboxylase deficiency, unspecified
D81.819, biotin-dependent carboxylase deficiency, unspecified, is listed as a covered diagnosis in 3 Medicare billing and coding articles that apply to 3 HCPCS Level II codes, including J3420 (Injection, vitamin b-12 cyanocobalamin, up to 1000 mcg), J3425 (Injection, hydroxocobalamin, intramuscular, 10 mcg), G0127 (Trimming of dystrophic nails, any number). The articles come from 2 Medicare contractors. A listed diagnosis supports medical necessity only; coverage still depends on the LCD's criteria and on documentation in the medical record.
HCPCS Level II codes with D81.819 as a covered diagnosis
| Code | Description | Medicare coverage | DMEPOS fee 2026 (state range) | Articles listing it |
|---|---|---|---|---|
| J3420 | Injection, vitamin b-12 cyanocobalamin, up to 1000 mcg | Special coverage instructions apply | — | 1 |
| J3425 | Injection, hydroxocobalamin, intramuscular, 10 mcg | Special coverage instructions apply | — | 1 |
| G0127 | Trimming of dystrophic nails, any number | Special coverage instructions apply | — | 2 |
Medicare policy articles listing D81.819
- A57755: Billing and Coding: Vitamin B12 Injections (First Coast Service Options, Inc. (MAC - Part B); 2 Level II codes). LCD with the same title: L33967
- A52996: Billing and Coding: Routine Foot Care (Novitas Solutions, Inc. (MAC - Part A, MAC - Part B); 1 Level II codes). LCD with the same title: L33941, L35138, L37643
- A57188: Billing and Coding: Routine Foot Care (First Coast Service Options, Inc. (MAC - Part B); 1 Level II codes). LCD with the same title: L33941, L35138, L37643
A diagnosis listed as covered in a billing and coding article supports medical necessity for the article's codes; it does not guarantee payment. Coverage depends on the LCD's criteria, the contractor's jurisdiction and documentation in the medical record.
Other D81 diagnoses (Combined immunodeficiencies)
- D81.810 — Biotinidase deficiency
- D81.818 — Other biotin-dependent carboxylase deficiency
- D81.82 — Activated Phosphoinositide 3-kinase Delta Syndrome [APDS]
- D81.89 — Other combined immunodeficiencies
- D81.0 — Severe combined immunodeficiency [SCID] with reticular dysgenesis
- D81.1 — Severe combined immunodeficiency [SCID] with low T- and B-cell numbers
- D81.2 — Severe combined immunodeficiency [SCID] with low or normal B-cell…
- D81.30 — Adenosine deaminase deficiency, unspecified
- D81.31 — Severe combined immunodeficiency due to adenosine deaminase deficiency
- D81.32 — Adenosine deaminase 2 deficiency
- D81.39 — Other adenosine deaminase deficiency
- D81.4 — Nezelof's syndrome
- D81.5 — Purine nucleoside phosphorylase [PNP] deficiency
- D81.6 — Major histocompatibility complex class I deficiency
- D81.7 — Major histocompatibility complex class II deficiency
- D81.9 — Combined immunodeficiency, unspecified
Frequently asked questions
Does Medicare cover D81.819 (Biotin-dependent carboxylase deficiency, unspecified)?
Medicare covers items and services, not diagnoses. 3 Medicare billing and coding articles list D81.819 as a covered diagnosis for 3 HCPCS Level II codes: the diagnosis can support medical necessity for those codes, but payment still depends on the LCD's coverage criteria and the medical record.
Which HCPCS codes can be billed with ICD-10 D81.819?
The Level II codes from the policies most specific to this diagnosis are J3420 (Injection, vitamin b-12 cyanocobalamin, up to 1000 mcg, 1 article); J3425 (Injection, hydroxocobalamin, intramuscular, 10 mcg, 1 article); G0127 (Trimming of dystrophic nails, any number, 2 articles). Code choice depends on the item supplied; check each code's descriptor.
Which Medicare policy articles list D81.819?
A57755 (Billing and Coding: Vitamin B12 Injections); A52996 (Billing and Coding: Routine Foot Care); A57188 (Billing and Coding: Routine Foot Care).
What is ICD-10-CM code D81.819?
D81.819 is the ICD-10-CM code for biotin-dependent carboxylase deficiency, unspecified, in category D81 (Combined immunodeficiencies), chapter 3: Diseases of the blood and immune mechanism.
Next steps
- Run a reimbursement report for a device billed under J3420
- Watch J3420 for fee, coverage and descriptor changes
- Build a full Medicare revenue model for J3420
Sources: CMS Medicare Coverage Database billing and coding articles (covered ICD-10 code lists and HCPCS links); ICD-10-CM FY2026; CMS HCPCS Level II release October 2026; CMS DMEPOS fee schedule 2026 (non-rural state fees). Not billing or legal advice.
Chapter 3: Diseases of the blood and immune mechanism · All diagnoses · HCPCS lookup