Abstract: SA-PO0836
Clinical Features and Long-Term Outcomes of Idiopathic Nephrotic Syndrome with Diffuse Mesangial Hypercellularity
Session Information
- Glomerular Management: Real-World Lessons and Emerging Therapies
November 08, 2025 | Location: Exhibit Hall, Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Glomerular Diseases
- 1402 Glomerular Diseases: Clinical, Outcomes, and Therapeutics
Authors
- Aoyama, Shuhei, Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
- Yamamura, Tomohiko, Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
- Yamamoto, Asahi, Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
- Kimura, Yuka, Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
- Inoki, Yuta, Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
- Sakakibara, Nana, Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
- Nagano, China, Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
- Horinouchi, Tomoko, Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
- Ishimori, Shingo, Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
- Yoshikawa, Norishige, Clinical Research Center, Takatsuki General Hospital, Osaka, Japan
- Nozu, Kandai, Department of Pediatrics, Kobe University Graduate School of Medicine, Hyogo, Japan
Background
Among childhood-onset idiopathic nephrotic syndromes(INS), diffuse mesangial hypercellularity(DMH) is a relatively rare histological finding(3-5%). There are limited reports describing its clinical characteristics, particularly regarding long-term outcomes.
Methods
Among INS patients treated at our hospital since 1995, those diagnosed with non-IgA DMH by renal biopsy were included. Based on the medical records, we retrospectively examined the clinical presentation and long-term prognosis of the patients. Data were expressed as median(interquartile range).
Results
21 patients were included, comprising 10 boys(48%), with age at diagnosis of 5.0(2.5-8.3) years. Indications for renal biopsy were hematuria in 16(76%), steroid-resistant NS(SRNS) in 3(14%), and acute kidney injury in 2(10%). Second renal biopsies were performed in 7 patients: 4 showed minimal change nephropathy(MCN), 2 had focal segmental glomerulosclerosis(FSGS), and 1 retained the diagnosis with DMH. Among 18 patients who underwent renal biopsy prior to treatment initiation, 5(28%) progressed to SRNS. All SRNS patients achieved remission with cyclosporine A(CyA) or methylprednisolone pulse therapy(MPT). Six of 21 patients(29%) developed frequent-relapsing or steroid-dependent NS(FR/SDNS), of whom 2(10%) were treated with rituximab. At the last follow-up, the age was 12.0(6.3-17.8) years, with follow up duration of 4.5(2.3-10.3) years. At the final visit, 3 patients(14%) were receiving angiotensin-converting enzyme inhibitors, 4(19%) were on immunosuppressive drugs, and 1(5%) was on prednisolone. 20 patients(95%) had no relapses within the last 2 years. No patients had hematuria. However, 1 patient had persistent proteinuria, and 1 patient had chronic kidney disease(CKD) stage 2 kidney dysfunction. No patients progressed to CKD stage 3 or higher. Both patients who had persistent proteinuria and CKD had FSGS at the second renal biopsy.
Conclusion
DMH presenting with NS exhibited a higher incidence of SRNS compared to MCN; however, all SRNS cases achieved remisson with CyA or MPT. In contrast, the frequency of FR/SDNS was comparable to that reported in pediatric MCN. At the last follow-up, disease relapses were well controlled and long-term kidney outcomes were favorable.