D84.1
Billable codeDefects in the complement system
The ICD-10 code for defects in the complement system is D84.1.
Clinical notes
Also known as
Alternate wording, synonyms, or specific conditions that fall under this code, listed to help confirm you've picked the right one.
- C1 esterase inhibitor [C1-INH] deficiency
Documentation support
General coding-documentation guidance — not a substitute for payer-specific requirements or professional coding judgment.
- •As a general rule, code to the highest level of specificity supported by the documentation in the medical record.
Related codes in this category
- D84.0Lymphocyte function antigen-1 [LFA-1] defect
- D84.8Other specified immunodeficienciesnon-billable header
- D84.9Immunodeficiency, unspecified
- D84.1Defects in the complement system
ICD-9-CM equivalent
Informational only — GEM mappings are approximate, not guaranteed one-to-one equivalents. Verify before use in billing.
- 2776Approximate match
- 2798Approximate match
Associated MS-DRGs
D84.1 can serve as the principal diagnosis for these Medicare Severity Diagnosis-Related Groups.
Informational only — actual DRG assignment also depends on procedures, complications/comorbidities (CC/MCC), discharge status, and payer-specific rules not reflected here.