Association between the time window of rash recurrence and the risk of renal involvement within 6 months in children with immunoglobulin A vasculitis.

@article{zheng2026association,
  title = {{Association between the time window of rash recurrence and the risk of renal involvement within 6 months in children with immunoglobulin A vasculitis.}},
  author = {Qian Zheng and Dongli Zhang and Xiangqiang Li and Ting Jiang and Tan Zhang and Xiujuan Fan},
  journal = {BMC pediatrics},
  year = {2026},
  month = aug,
  doi = {10.1186/s12887-026-07456-4},
  url = {https://europepmc.org/article/MED/42972284},
  note = {CC BY-NC-ND},
}

TY  - JOUR
TI  - Association between the time window of rash recurrence and the risk of renal involvement within 6 months in children with immunoglobulin A vasculitis.
AU  - Qian Zheng
AU  - Dongli Zhang
AU  - Xiangqiang Li
AU  - Ting Jiang
AU  - Tan Zhang
AU  - Xiujuan Fan
PY  - 2026
DA  - 2026/08/04
JO  - BMC pediatrics
DO  - 10.1186/s12887-026-07456-4
UR  - https://europepmc.org/article/MED/42972284
AB  - Background  Renal involvement is a major determinant of long-term outcome in childhood immunoglobulin A vasculitis (IgAV). We examined whether the timing of the initial rash recurrence was associated with renal involvement within 180 days, while accounting for temporal ordering, rash phenotype, and surveillance intensity.Methods  This single-center retrospective cohort included 302 children with newly diagnosed IgAV from 2020 to 2024. Rash recurrence was modeled as a time-varying exposure: all children entered a not-yet-recurrent state and, at the initial recurrence, moved to the ≤ 14-, 15-30-, 31-60-, or 61-180-day state. The primary outcome was the initial confirmed renal event within 180 days. Multivariable time-varying Cox regression, Simon-Makuch curves with the Mantel-Byar test, and prespecified sensitivity analyses were used.Results  Ninety-four children (31.1%) developed renal involvement. Seventy events occurred after documented recurrence and 24 while children remained in the not-yet-recurrent state; eight of the latter recurred only after the renal event and were not retrospectively reclassified. Compared with the not-yet-recurrent state, recurrence at 15-30 days (adjusted hazard ratio [aHR], 1.86; 95% confidence interval [CI], 1.03-3.37; P = 0.040), at 31-60 days (aHR, 3.18; 95% CI, 1.73-5.83; P < 0.001), and at 61-180 days (aHR, 2.72; 95% CI, 1.25-5.90; P = 0.011) were associated with higher renal-event hazards, whereas recurrence within 14 days was not significantly associated. Extensive and bullous skin involvement was more frequent in unadjusted comparisons but was not independently associated in separate exploratory models. Children with recurrence recorded before event or censoring had more clinical-contact and urine-assessment days. In the surveillance-complete subset, associations persisted for 31-60 and 61-180 days, whereas the 15-30-day estimate was attenuated. Simon-Makuch curves differed (Mantel-Byar P < 0.001).Conclusions  Delayed rash recurrence, particularly at 31-60 days, was associated with renal involvement within 6 months. Standard renal surveillance remains necessary for every child with IgAV; recurrence timing may provide additional information for identifying children who warrant closer vigilance. Residual surveillance bias and the observational design limit causal interpretation.
SN  - 1471-2431
ER  -