Familial Behçets-like Autoinflammatory Syndrome; Autoinflammatory syndrome, familial, Behcet-like (AISBL); Haploinsufficiency of A20 (HA20)
A20 deficiency; NF-κB regulatory protein A20 (still being classified)
Unknown. Patients of Turkish, European or Japanese ancestry in the current literature.
Rare. Some families with a few affected members for generations. Some patients were previously diagnosed as having Behçets.
Timing of symptoms:
Most cases have symptoms start in childhood with oral and genital ulcers, uveitis and vasculitis that mimic Behçets disease. Some with arthralgia, and/or polyarthritis. A few have periodic fevers.  (along with the supplement).
Age of onset:
Onset of symptoms in early childhood in most cases, with oral and genital ulcers, uveitis and other findings that present similar to Behçets. One case developed in infancy-most present with their symptoms between 2-16 years of age. (supplement).
Oral and genital ulcers (that look similar to Behçets lesions) axillary and dermal abscesses.  Pathergy test is positive in some patients. A few have other skin rashes, such as erythematous papules, folliculitis or a malar rash.  (supplement.)
One case with central nervous system (CNS) vasculitis, chorea and migraine headaches. One other patient with headaches.  (plus supplement).
Unknown at this time. 
Anterior uveitis (may be bilateral), chorioretinal scarring, macular fibrosis (secondary to retinal vasculitis) causing impaired vision. Ocular inflammation is common.  (and supplement).
Unknown. One case of pericarditis in infancy. One case of idiopathic thrombocytopenic purpura (ITP)  (supplement).
A few with colitis (one case was mild, and undifferenciated). Findings include ulcers in the oropharynx, terminal ileum or colon. One case with nausea, vomiting, weight loss. Inflammation on biopsy of the gastrointestinal tract.  (supplement).
A few with lymphopenia, IgG 2, or 2 and 4 subclass deficiencies and low polysaccaride antibodies. (supplement).
Joints bones muscles cartilage:
Arthralgia, with or without polyarthritis (non-deforming) in the large and small joints. Small joint polyarthritis was the most predominant. Tendonitis in one patient. Some patients have been misdiagnosed as having systemic lupus erythematosis (SLE, Lupus). 
Vasculitis, retinal vasculitis.  One case with idiopathic thrombocytopenic purpura (ITP).
During flares of symptoms, patients may have elevated CRP, ESR or other inflammatory markers. A few have autoantibodies, or weak positive autoantibodies, such as: Lupus anticoagulant, anti dsDNA, anticardiolipin, RNP, ANA, Some also have HLA-B51, or HLA-B15, or HLA-B39/B44 noted. A few with lymphopenia, IgG 2, or 2 and 4 subclass deficiencies and low polysaccaride antibodies. One case with hemolytic anemia reported, and another with idiopathic thrombocytopenic purpura (ITP).  (supplement).
uveitis, oral ulcers, genital ulcers, mouth sores, genital sores, oral lesions, genital lesions, oral and genital ulcers, oral and genital, oral, genital. Behçets, abscess, abscesses, axillary abscess, dermal abscess, pathergy, retinal vasculitis, vaculitis, polyarthritis, arthritis, chorioretinal scarring, retinal scarring, macular fibrosis, fibrosis, arthralgia, ocular, ocular inflammation, SLE, Lupus, behcets, systemic lupus, headache, chorea, lymphopenia, HLA, colitis, polysaccaride antibodies, idiopathic thrombocytopenic purpura, ITP, Lupus anticoagulant, anti dsDNA, anticardiolipin, RNP, ANA, low IgG, IgG, IgG2, IgG4, autoantibodies, small joint polyarthritis, HA20, abdominal pain,Haploinsufficiency of A20
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