Background BD is rarely encountered in children where the disease is very difficult to recognize. The outcome of patients with few symptoms is currently unknown
Objectives To define the outcome of paediatric patients with at least two symptoms of BD, and to obtain an appropriate definition of BD in patients <16y
Methods An international expert committee has defined the criteria of inclusion. New patients or patients followed for a maximum of 3 years, who presented at least 2 symptoms of BD (among a list), and gave their informed consent were included, reviewed yearly.
Results 223 patients (SR: 1), from 22 centres of 12 countries, were included since 2008, median age of 13,3y (2.3-21y). Median age at first symptom was 8y (9m-18y). Family history of BD was present in 50 (22.4%) and consanguinity in 10 (4.5%). Median disease duration at inclusion was 4.7y (0-16,5y) and from the first symptom to last visit was 5.5y (1m-19.4y). Inclusion criteria plus oral aphtosis (mandatory) were (%): genital aphtosis 51.1, necrotic folliculitis 31.4, uveitis 28.7, familial history 22%, pathergy test positive 18.8, erythema nodosum 14.3, vascular 10 and retinal vasculitis 7.2. Mean number of symptoms: 1 plus family history (41%), 2 (33%), more than 3 (26%). Patient had a median of 1.0 follow-up visit (0-4). 217 patients had a first visit: where symptoms were as follows (%): genital aphtosis 49, skin lesions 49, joints and fever 41, eyes lesions 35, neurological 34.5, gastrointestinal 30.5 and vascular16.5. HLAB51 was present in 48% and A26 in 4%. Male patients had significantly more uveitis. 138 patients had a 1-y visit (mean BD duration: 5.6y). 81 patients had 2-y (6.3y), 44 a 3-y (7.2y) and 18 a 4-y visit (7.4y). Between 1st-4th visit: 62% had no new symptom, 23% had one, and 8% had 2 and 7 had more than 3. The expert committee has reviewed 196 files at a median disease duration of 6,7y (0.9-19y), and classified 118 patients as definite, 21 as probable and 3 as not BD. 54 charts were reviewed but did not reached consensus. 45 files have been reviewed more than once. Although good concordance (Kappa coefficient = 0.72), International criteria and expert classification showed significant differences: 60.2% (118/196) patients were classified as definite BD by experts, whereas only 45.9% of these patients met the international criteria (P<0.0001). Having 2 or more symptoms was significantly associated with classification as definite BD (p=0.0005).
Conclusions The expert committee has classified the majority of patients in the BD group although they did not fulfil the international BD classification criteria (for adults)
Disclosure of Interest None Declared