Background BD is rarely encountered in patients before 16y where the disease is very difficult to recognize. In addition to the diagnostic challenge, the outcome of patients with few symptoms is currently unknown.
Objectives PED-BD is an international database aimed to define the outcome of either paediatric BD patients or patients with at least two symptoms of the disease, in order to propose paediatric criteria for BD.
Methods An international expert committee has defined criteria for eligibility in the study. New patients or patients followed for a maximum of 3 years, who presented at least 2 symptoms of BD (among a list), were selected for retrospective and prospective analyses. An eCRF was built and inserted into a secured database (CLeanWeb). Patients included are reviewed yearly and judged as definite, probable or not BD, by an expert committee.
Results 206 patients (SR:1), from 22 centres of 12 countries, have been included since 2008, median age 13,5y (2,3-21y). Median age at onset was 8y (9m-18y), family history was 22,3% and consanguinity 4.4%. At inclusion, median disease duration from onset to last visit was 5.5y (1m-19y). The criteria of inclusion in addition to oral aphtosis (mandatory): genital aphtosis 52%, necrotic folliculitis 30%, uveitis 29%, familial history 22%, pathergy positive 19%, erythema nodosum 14,5%, skin ulceration 11%, vascular 8,7% and retinal vasculitis 7%. Number of symptoms: 1 plus family history (42,7%), 2 (30,6%), more than 3 (26,7%). Patient had a median of 1 follow-up visit (0-4). 200 patients had a first visit, symptoms as follows: Skin lesions 58%, joints and fever 41%, eyes lesions 36%, neurological 34%, gastrointestinal 29% and vascular (12%). 84% received treatment: colchicine 59%, steroids 29%, azathioprine 12% and MTX 9%. Male patients had significantly more uveitis. 135 patients underwent first year visit. 62 had no new symptom, 43 had one, and 15 had 2 and 15 had 3. 73 patients had a 2y, 37 a 3y and 17 a 4y visit. The expert committee has reviewed 114 files at a median disease duration of 6,2y (0-18y), and classified 72 patients has definite, 44 as probable and 2 as not BD. Among patients classified as BD: 57 met the international criteria. Symptoms associated with classification as definite were skin (74% of the definite had this symptom), genital aphtosis (67%), eyes (51%) and pathergy (26%). None of the symptoms were observed in patients not classified as definite. The Kappa concordance coefficient between the 2 classifications reached 0.73 with a 95% CI= [0.62-0.86].
Conclusions The PED-BD cohort is characterized by an equal sex ratio, a high rate of familial aggregation, and marked phenotypic differences by gender. In this large series of patients with few symptoms, the expert committee judgments gave higher number of patients classified as BD than the classification by the international classification criteria.
Disclosure of Interest None Declared