The demographic and clinical features of pediatric patients diagnosed with systemic vasculitides were documented. Results of the study were published in APR Rheumatology.

Researchers determined the distribution for each kind of vasculitis and then compared these data with those of other international studies. For each kind of vasculitis, the most relevant and frequently seen symptoms were selected based on the diagnostic criteria, evidence found in literature, and clinical experience.

Patients (N=138) included in the study were younger than 18 years and had been admitted to a tertiary center at diagnosis or during follow-up from 2009 to 2020.

Patients with Kawasaki disease (KD) were the youngest, with a median age at diagnosis of 2.26 years (IQR, 1.07-6.20 years). Those with Behçet syndrome had a median age at diagnosis of 13.41 years (IQR, 10.19-16.75 years), which was significantly higher (P <.05).

Although not significantly different between the groups, slightly more girls than boys were diagnosed with Behçet syndrome, with a male to female ratio of 0.64:1.

The prevalence of KD was found to differ according to ethnicity, with a higher prevalence among those of Asian descent.

Cutaneous involvement was noted in 87.7% of all patients and in more than 90% of patients with IgA vasculitis (formerly known as Henoch-Schönlein purpura) and KD. All patients with Behçet syndrome had recurrent oral aphthous ulcers and 87% had genital ulcers.

Patients with KD experienced a mean duration of fever of 9.6±2.1 days, which was longer than expected.

Gastrointestinal symptoms affected 15% to 50% of patients across all groups, but affected fewer of those with BS (17%).

Arthritis and arthralgia were observed in 65% of those with IgA vasculitis, with joint involvement affecting 27% of patients with KD.

Kidney manifestations in patients with IgA vasculitis were less prevalent than expected (11%).

Ophthalmic involvement in patients with Behçet syndrome (22%) were also less prevalent than expected. Among patients with KD, 70.3% had ophthalmic involvement, typically bilateral conjunctivitis. Among patients with Behçet syndrome, 21.7% presented with ophthalmic symptoms, most often panuveitis.

Patients with Behçet syndrome had a 30% higher prevalence of vascular events.

The study included 3 patients who met the diagnostic criteria for polyarteritis nodosa, and all 3 patients had hypertension requiring medication and central nervous system involvement including intracerebral hemorrhage, brain and spinal strokes, and oculomotor nerve palsy and hemiparesis. In pediatric patients with diagnostic criteria for polyarteritis nodosa, clinicians should consider a deficit of adenosine deaminase 2.

Only 1 patient in the study was diagnosed with Takayasu arteritis. Aged 9 years, the patient presented with signs of hypertension and kidney dysfunction.

IgA vasculitis usually was found to have a self-limited course with few or no further complications.

Because KD can affect the coronary arteries, the researchers emphasized the importance of early identification and treatment to reduce aneurysms that could result in severe outcomes, including death.

Behçet syndrome, which often manifests in the second and third decades of life, may follow a chronic course of remission and relapse, with disease severity decreasing with age. Being male and younger at disease onset may suggest a worse prognosis.

Limitations of the study included its retrospective design and the omission of 4% of the study participants due to missing data. In addition, the majority of patients were Portuguese and White.

According to the study authors, “Most of our findings are in concordance with current literature, with some notable exceptions, mainly concerning renal involvement in IgA [vasculitis], fever duration and articular manifestations in KD and ophthalmic involvement and vascular events in [Behçet syndrome].”