Children with IgA vasculitis who present with severe persistent skin manifestations, such as hemorrhagic vesicles, ulceration, or necrosis, are at higher risk for relapse and should be followed for a longer period, according to research findings presented at the 22nd International Vasculitis Workshop (IVW) 2026.

Pediatric rheumatologist Marija Jelusic, MD, PhD, of the University of Zagreb School of Medicine in Croatia, presented data from a national cohort study of 808 children diagnosed with IgA vasculitis. They were followed for a median of 56 months to provide prospective and retrospective insights into the risk factors for relapse and severe disease.

IgA vasculitis is the most common systemic vasculitis in childhood, with the incidence ranging from 3 to 55 per 100,000 children, Jelusic told conference attendees. Around 30% of those with the disease will experience at least one relapse, defined as recurrence of any IgA vasculitis symptoms after ≥ 4 weeks of complete remission, with most relapses occurring in the first 6 months after the initial episode.

“In children, IgA vasculitis is typically a self-limiting disease with a good prognosis, but it is important to keep in mind that various acute and chronic complications are possible,” she said. 

The most concerning of those complications were those affecting the gastrointestinal tract and kidneys, and it’s unclear how relapses contribute to the risk for those more severe outcomes. “The majority of studies show children with relapse had a higher cumulative rate of nephritis, but there is no consistency regarding renal outcomes,” Jelusic said.

The study involved a retrospective analysis of 624 patients diagnosed between 2009 and 2019 and a prospective analysis of 184 patients, looking for associations between clinical variables, time to relapse, and outcomes.

At baseline, 22% of patients had evidence of nephritis, 46.1% had gastrointestinal manifestations, 80% had arthritis or arthralgia, and 3.6% had severe skin manifestations.

The 178 patients with nephritis were generally older, with a median age of 7.5 years at diagnosis, and with more severe presentation, including rash, GI manifestations, and hypertension. One third presented with erythrocyturia and proteinuria, 38% with isolated erythrocyturia, 13% with nephritic syndrome, and 6% with nephrotic syndrome.

The retrospective analysis suggested that severe rash, nephritis, isolated hematuria, and long-term rash were all independently and strongly associated with the risk for relapse. Long-term rash was associated with an eightfold increase in the risk for relapse and was also the strongest predictor of relapse severity, while severe skin manifestations were associated with a more than 11-fold increase in the risk for relapse.

Overall, 84.8% of patients had a favorable outcome at 12 months, with normal physical examination and normal urinary and renal function; 14.1% still had hematuria and/or proteinuria and/or hypertension; and 1.1% progressed to renal failure.

Identifying Patient Clusters at Greater Risk for Relapse

The researchers also performed a cluster-based risk analysis of clinical and laboratory features of disease to see if there were unique groups of patients at greater risk for relapse. 

This revealed that the cluster with the highest relapse rate was that in which all patients had renal disease and skin manifestations, many had arthritis, and around half had GI symptoms; this group’s median age was 7.6 years. The lowest relapse rate was seen in the cluster of younger patients, all of whom had arthritis as well as elevated erythrocyte sedimentation rate and C-reactive protein levels.

Speaking to Medscape Medical News, Jelusic said those who developed nephritis usually did so in the first few weeks after diagnosis, but it could also emerge 6 months or longer after diagnosis. 

“If your patient has this skin manifestation, and also if manifestation persists more than 1-3 months, you should follow up patients not only for 6 months, but for 12 months and even longer because nephritis could develop,” she said. That was particularly the case for patients with severe skin manifestations or severe GI presentations.

Commenting on the presentation, David Jayne, MD, professor of clinical autoimmunity at the University of Cambridge and director of the vasculitis and lupus service at Addenbrooke’s Hospital, Cambridge, United Kingdom, said there had been little progress in IgA vasculitis for decades, so it was significant to have a growing network of centers around the world now focusing on the disease.

“For the vast majority of kids, this is a single shot of disease from which they recover, but there’s a small percentage that do badly,” Jayne said. “Because the whole thing is relatively common in children, that’s an important group.”

Jelusic did not have any funding and reported no relevant financial relationships. Jayne has declared consultancies, honoraria, advisory board payments and lecture fees from a number of pharmaceutical companies, and stock options or bond holdings from Aurinia Pharmaceuticals.