Abstract
Introduction: Childhood vasculitis is an umbrella term that describes a group of disorders that are characterized by inflammation of blood vessel walls. It could be primary or due to secondary causes. Clinical manifestations are heterogeneous and depend mainly on the size of the vessels involved. Objectives: To report the spectrum and clinical manifestations of childhood vasculitis other than Kawasaki disease (KD) and Henoch- Schoenlein Purpura (HSP) in Arab children, and to highlight the longterm outcome. Methods: We conducted a multicenter retrospective study recruiting patients with childhood vasculitis other than KD and HSP during the period between January 2000 and May 2022, from ten Pediatric Rheumatology clinics in seven Arab countries that are members of the Pediatric Rheumatology Arab Group (PRAG). The collected data comprised demographic and clinical findings, and long-term outcome using the Pediatric Vasculitis Damage Index (PVDI). Results: A total of 150 (78 female) patients diagnosed with childhood vasculitis other than KD and HSP before 14 years old with a median age at onset was 7.2 (IQR 4.3-11) years were enrolled. The initial diagnosis was inaccurate in 59.3% and the interval time to diagnosis was 0.5 (IQR 0-1) years. Consanguinity among parents was 42% and positive family history of vasculitis was (n=18, 12%). The most frequent vasculitis was Bechet’s disease (n=37, 24.6%) followed by ANCA associated Vasculitis (n=24, 16%), Takayasu arteritis (n=16, 10.6%), Polyarteritis nodosa (PAN) (n=15,10%) and cutaneous PAN (n=14, 9.3%). The most common clinical manifestations were fever (n=90, 60%), abdominal pain (n=74, 50%), arthralgia (n=64, 42.6%), headache (n=53, 35%), hypertension (n=43,28%), and palpable purpura (n=31, 20.5%). Most patients had elevated inflammatory markers (73%). ANA was positive in 22%, C-ANCA and P-ANCA were positive in 12% of patients. Angiography showed abnormalities in 22%, while echocardiography was abnormal in 21%. Tissue biopsy was performed in 65 patients. Genetic analysis was done in 36 patients; 19 patients had genetic variants. Most patients (84.7%) received corticosteroids with good response. One hundred-thirty-five patients received immunosuppressive therapy; cyclophosphamide used in 23 patients with good response. Fifty-seven patients used biologic agents, the most frequently used biologic agents was Rituximab (n= 18) followed by Infliximab (n= 12) and Tocilizumab (n= 11) with overall improvement more than 90%. The PVDI showed renal complication (8%) with ESRD (2.5%), cardiomyopathy (7.3%), osteoporosis (6%), and blindness (2.4%). No reported bone marrow depression or malignancies. However, there were four deaths related to the disease or comorbidities. Conclusion: This study presents the first and largest data on childhood vasculitis other than KD and HSP in Arab children. It shows a heterogenous spectrum of vasculitis with high prevalence of genetically confirmed vasculitis. This report intended to increase awareness of these diseases among health care providers. Hopefully, this work will be the first step for a prospective registry for childhood vasculitis in Arab countries.