TOPLINE:

Approximately one quarter (23.4%) of children with juvenile idiopathic arthritis (JIA) developed acute kidney injury (AKI) at disease onset, with younger age, elevated levels of C-reactive protein, and antinuclear antibody positivity identified as independent predictors. AKI at the onset of JIA was associated with increased odds of long-term kidney damage.

METHODOLOGY:

• Researchers conducted a retrospective study to evaluate the prevalence and risk factors for AKI at the onset of JIA and its impact on long-term kidney outcomes.
• They included 192 patients diagnosed with JIA (mean age at diagnosis, 6.7 years; 29.2% boys), each with at least two follow-up visits within a 1-year interval.
• Clinical and laboratory data were collected at diagnosis and during follow-up visits, which were evaluated monthly until clinical remission and then every 3 or 6 months according to disease activity and treatment.
• The primary outcome was the occurrence of AKI at the diagnosis of JIA.
• The secondary outcome was the development of kidney damage, defined as chronic kidney disease (CKD; an albumin-to-creatinine ratio ≥ 30 mg/g persisting for more than 3 months or an estimated glomerular filtration rate < 90 mL/min/1.73 m² for more than 3 months) and/or hypertension during follow-up.

TAKEAWAY:

• At the onset of JIA, 45 (23.4%) patients developed AKI, predominantly stage 1, with none requiring haemodialysis.
• Younger age (per 1-year decrease; adjusted odds ratio [aOR], 1.2; P = .002), elevated levels of C-reactive protein (per 10 mg/L increase; aOR, 1.1; P = .007), and antinuclear antibody positivity (aOR, 4.1; P < .001) were identified as independent risk factors for AKI at the onset of JIA.
• After a mean follow-up of 6.3 years, 23 (12%) patients developed kidney damage: 19 had CKD, four had hypertension, and two had both. Patients with AKI at the onset of JIA had around sixfold increased odds of developing kidney damage at the last follow-up (aOR, 5.8; P < .001).
• At 25.1 years of age, the cumulative proportion remaining free from kidney damage was significantly lower among patients with AKI than among those without AKI at the onset of JIA (26.9% vs 64.1%; P = .005).

IN PRACTICE:

"This [the study finding] highlights for all pediatric rheumatologists the importance of assessing kidney function at the time of JIA diagnosis and of monitoring blood pressure, kidney function, and proteinuria during follow-up visits," the authors wrote.

SOURCE:

This study was led by Maria Francesca Gicchino, Università degli Studi della Campania "Luigi Vanvitelli," Naples, Italy. It was published online on March 03, 2026, in Pediatric Nephrology.

LIMITATIONS:

The retrospective design of the study prevented the establishment of definitive causal relationships. The Kidney Disease: Improving Global Outcomes urine output criteria for AKI were not used due to unavailable data. Additionally, the study could not assess urinary microscopy due to insufficient data.

DISCLOSURES:

This study did not report any specific funding. The authors declared having no competing interests.

This article was created using several editorial tools, including AI, as part of the process. Human editors reviewed this content before publication.