SynopsisCodesLook ForDiagnostic PearlsDifferential Diagnosis & PitfallsBest TestsManagement PearlsTherapyReferences
Deficiency of adenosine deaminase type 2
Other Resources UpToDate PubMed

Deficiency of adenosine deaminase type 2

Contributors: Vivian Wong MD, PhD, Susan Burgin MD
Other Resources UpToDate PubMed


Deficiency of adenosine deaminase type 2 (DADA2) is a rare multisystem vasculopathic syndrome. It is an autosomal recessive disorder caused by loss-of-function mutations in the Cat Eye Syndrome Chromosome Region Candidate 1 (CECR1) gene on chromosome 22q11, which encodes the adenosine deaminase type 2 (ADA2) enzyme. While some carriers are asymptomatic, many develop significant clinical disease affecting multiple systems, including immunodeficiency with recurrent infections, intermittent fevers, livedo racemosa, childhood-onset polyarteritis nodosa (PAN), and systemic vasculopathy, including early-onset recurrent strokes and Sneddon syndrome. DADA2 syndrome is a rare condition, with an estimated prevalence of 4 per 1 million per year in the general population.


D81.32 – Adenosine deaminase 2 deficiency

44940001 – Adenosine deaminase deficiency

Look For

Subscription Required

Diagnostic Pearls

Subscription Required

Differential Diagnosis & Pitfalls

Differential for PAN:
  • Pyoderma gangrenosum
  • Antiphospholipid antibody syndrome
  • Necrotizing Vasculitis
  • Cryoglobulinemia
  • Cryofibrinogenemia
  • Cutaneous anthrax
  • Necrotizing fasciitis
  • Acute meningococcemia
  • Calciphylaxis
  • Disseminated intravascular coagulation (DIC)
  • Microscopic polyangiitis
  • Immunoglobulin A vasculitis (formerly Henoch-Schönlein purpura)
  • Systemic lupus erythematosus (SLE)
  • Eosinophilic granulomatosis with polyangiitis (formerly known as Churg-Strauss syndrome)
  • Thrombotic thrombocytopenic purpura (TTP)
  • Granulomatosis with polyangiitis (formerly known as Wegener granulomatosis)
  • Sarcoidosis
  • Sporotrichosis
  • Erythema nodosum
  • Nodular vasculitis
  • Lymphomatoid granulomatosis
  • Mucormycosis
  • Cocaine levamisole toxicity
Differential for livedo changes:
  • Livedo reticularis
  • Livedoid vasculopathy
  • Erythema ab igne
  • Cutis marmorata telangiectatica congenita
  • Collagen vascular diseases or Vasculitis (Polyarteritis nodosa, Systemic lupus erythematosus, Rheumatoid arthritis, Dermatomyositis)
  • Hematologic or hypercoagulable conditions (Antiphospholipid antibody syndrome, Cryoglobulinemia, Polycythemia vera, Protein C deficiency or Protein S deficiency, Heparin-induced thrombocytopenia, Thrombotic thrombocytopenic purpura / Hemolytic uremic syndrome, Paroxysmal hemoglobinuria, etc)
  • Livedoid vasculopathy

Best Tests

Subscription Required

Management Pearls

Subscription Required


Subscription Required


Subscription Required

Last Updated:12/13/2018
Copyright © 2024 VisualDx®. All rights reserved.
Deficiency of adenosine deaminase type 2
A medical illustration showing key findings of Deficiency of adenosine deaminase type 2 : Hepatosplenomegaly, Intermittent fevers, Livedo racemosa
Copyright © 2024 VisualDx®. All rights reserved.