| Assessing kidney outcomes in childhood-onset lupus
nephritis: role of National Institutes of Health-modified
histological indices |
Nuanpan Penboon 
, Pornpimol Rianthavorn
|
|
Department of Pediatrics, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand |
Correspondence:
Pornpimol Rianthavorn, Email: pornpimol.r@chula.ac.th
|
|
Received: 8 June 2025 • Revised: 29 July 2025 • Accepted: 22 August 2025 |
|
|
| Abstract |
Background
Childhood-onset lupus nephritis (cLN)
is an aggressive disease. Although histological class has
historically guided its treatment, its prognostic value
remains limited. Although the National Institutes of
Health (NIH)-modified activity index (AI) and chronicity
index (CI) incorporate glomerular and tubulointerstitial
changes and may provide better prognostic insight, their
utility in cLN is not well established.
Purpose
Here we aimed to assess the utility of the
NIH-modified-modified AI and CI for predicting kidney
outcomes and identify histopathological features and
treatment-related factors associated with the development
of kidney function impairment in cLN.
Methods
We retrospectively analyzed 60 children
with biopsy-proven proliferative lupus nephritis. Their
baseline clinical and histological features, treatments, and
outcomes were assessed. The association between AI and
CI scores, along with individual histological components,
and kidney function impairment, defined as an estimated
glomerular filtration rate < 90 mL/min/1.73 m² sustained
for ≥3 months, was evaluated.
Results
Over a median follow-up of 55.5 months, 30%
of patients developed kidney function impairment. AI
scores and glomerular lesions did not differ significantly
between patients with and without kidney function
impairment. However, the CI scores were significantly
higher in patients who developed kidney function
impairment, with tubular atrophy and interstitial fibrosis
being the most predictive components. On a multivariate
analysis, tubular atrophy was an independent predictor
of kidney function impairment (hazard ratio [HR], 17.74;
95% confidence interval [CI], 1.94–162.5; P=0.01). Use of
mycophenolate mofetil (MMF) as maintenance therapy
was associated with a reduced risk of kidney function
impairment (HR, 0.09; 95% CI, 0.02–0.47; P=0.003).
Conclusion
Chronic tubulointerstitial changes, particularly
tubular atrophy, are a stronger predictor of
long-term kidney function than glomerular findings
or AI scores. These findings highlight the prognostic
value of NIH-modified CI and the importance of MMF in
maintenance therapy. The early identification of chronic
lesions on biopsy may guide therapeutic decisions aimed
at preserving kidney function and improving long-term
outcomes in patients with cLN. |
| Key Words:
Chronicity index, Kidney failure, Lupus
nephritis, Mycophenolic acid, Tubulointerstitial fibrosis |
|
PDF Links
Download Citation
