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Start free with EleplanHypocomplementemic urticarial vasculitis
ORPHA:36412Disease
Also called Anti-C1q vasculitis · Mac Duffie hypocomplementemic urticarial vasculitis · Mac Duffie syndrome · McDuffie hypocomplementemic urticarial vasculitis · McDuffie syndrome
What it is
A rare immune complex-mediated small vessel vasculitis characterized by urticaria and hypocomplementemia (low C3, C4 and/or C1q), and usually associated with circulating anti-C1q autoantibodies. Arthritis, pulmonary disease, ocular inflammation are common systemic manifestations.
Key facts
- Age of onset
- Adult, Childhood
- Inheritance
- Autosomal recessive, Not applicable
- Classified as
- Disease
Signs and symptoms
Common30–79%
17Sometimes5–29%
26- Abnormal heart valve morphology
- Airway obstruction
- Ascites
- Ataxia
- Cerebral palsy
- Cranial nerve paralysis
- Diarrhea
- Emphysema
and 18 more in this range
These ranges are how often a sign appears across everyone diagnosed, not a prediction for one person — most people have some of these and not others. Orphanet also records findings that are specifically absent in this disease; those are in the data but not listed here.
Gene
ICD-10 codes
ICD-10 has no distinct code for most rare diseases, so many are filed under the nearest available one. A shared code identifies the group, not this disease — the ORPHAcode above is what identifies it.
Related health topics
Reached through the ICD-10 categories this disease is filed under, so these describe the broader group rather than this disease specifically.
Cross-references
Orphadata Science: Free access data from Orphanet. © INSERM 1999. Data version 2026-06-23. Available under CC BY 4.0. This is a reference, not medical advice.
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