`D84.1` Defects in the complement system

Billable ICD-10-CM code, FY2026.

Risk adjustment (HCC)

CMS-HCC V28: HCC 115 — Specified Immunodeficiencies and White Blood Cell Disorders
CMS-HCC V22: HCC 23 — Other Significant Endocrine and Metabolic Disorders
RxHCC V08: HCC 98 — Hereditary Angioedema and Other Defects in the Complement System
ESRD V24: HCC 23

Defines the logic of DRG(s) 642 in MDC 10.

Code Also: D59.32 Hereditary hemolytic-uremic syndrome ("defects in the complement system (D84.1)")
Type 1 Excludes: D84.81 Immunodeficiency due to conditions classified elsewhere ("certain disorders involving the immune mechanism (D80-D83, D84.0, D84.1, D84.9)")
Type 1 Excludes: L50 Urticaria ("hereditary angio-edema (D84.1)")

Type 1 Excludes: D72 Other disorders of white blood cells ("immunity disorders (D80-D89)")

Angioedema (allergic) (any site) (with urticaria) › hereditary
Angioneurotic edema (allergic) (any site) (with urticaria) › hereditary
Bannister's disease › hereditary
Defect, defective › complement system
Deficiency, deficient › C1 esterase inhibitor (C1-INH)
Edema, edematous (infectious) (pitting) (toxic) › angioneurotic (allergic) (any site) (with urticaria) › hereditary
Edema, edematous (infectious) (pitting) (toxic) › circumscribed, acute › hereditary
Edema, edematous (infectious) (pitting) (toxic) › essential, acute › hereditary
Edema, edematous (infectious) (pitting) (toxic) › glottis, glottic, glottidis (obstructive) (passive) › allergic › hereditary
Edema, edematous (infectious) (pitting) (toxic) › periodic › hereditary
Edema, edematous (infectious) (pitting) (toxic) › Quincke's › hereditary
Giant › urticaria › hereditary
Quincke's disease or edema › hereditary
Urticaria › with angioneurotic edema › hereditary
Urticaria › giant › hereditary
Urticaria › larynx › hereditary