Abstract: SA-PO441
Clinical Relevance of C4d Deposition in Pediatric IgA Nephropathy
Session Information
- Pediatric Nephrology - II
October 27, 2018 | Location: Exhibit Hall, San Diego Convention Center
Abstract Time: 10:00 AM - 12:00 PM
Category: Pediatric Nephrology
- 1600 Pediatric Nephrology
Authors
- Cho, Min Hyun, Kyungpook National University Hospital, Daegu, Korea (the Republic of)
- Jung, Jaehun, Kyungpook National University Hospital, Daegu, Korea (the Republic of)
- Kim, Yong-Jin, Kyungpook National University Hospital, Daegu, Korea (the Republic of)
- Han, Man-hoon, Kyungpook National University Hospital, Daegu, Korea (the Republic of)
- Baek, Hee Sun, Kyungpook National University Hospital, Daegu, Korea (the Republic of)
Background
Immunoglobulin A nephropathy (IgAN) is one of the most common causes of primary glomerulonephritis and is characterized by predominant IgA deposition in the glomerulus mesangium. Recently, it has been well-known that the activation of complement system plays an important role in the development and progression of IgAN. The aim of this study is to investigate the association between the evidence of C4d staining and clinical or histopathologic features of pediatric IgAN patients.
Methods
Fifty-six pediatric patients diagnosed with IgA nephropathy through renal biopsy from 2006 to 2017 were reviewed retrospectively. Immunohistochemical C4d staining was performed in all biopsy tissues. Clinical/histopathological features were statistically analyzed according to C4d staining positivity.
Results
A total of 56 patients (male 58.9%, female 41.1%) were included in the study and the mean age at diagnosis was 12.1 ± 4.7 years. Among the 56 patients, 31 (55.4%) showed positive glomerular C4d staining; a mesangial (n=16), a peripheral capillary (n=11), or a mixed (n=4) distribution pattern. Urine protein-to-creatinine ratio was significantly higher in C4d-positive patients (p = 0.001). The severity of mesangial proliferation according to the Haas and Oxford classification were significantly associated with positive C4d staining (p < 0.001). In the Haas classification, the positive rate of C4d in patients with subclass I was 12.9% (n=4), but in them with subclass III and IV were 45.2% (n=14) and 38.7% (n=12), respectively. In addition, as for the Oxford classification of IgAN, positive C4d staining turned out to be significantly associated with the evidence of mesangial proliferation (M1) (p<0.001). The positive rate of C4d in patients with M1 was 67.7% (n=21), but in them with M0, 32.3% (n=10). However, there was no significant association of the evidence of endocapillary hypercellularity, segmental sclerosis, and tubulointerstitial fibrosis/atrophy between the patients with positive C4d and them with negative C4d. Additionally, as for C4d staining patterns such as mesangial, peripheral capillary or mixed patterns, there was no significant correlation between these patterns and histologic severity of the Haas or Oxford classification.
Conclusion
Positive C4d staining was found to be significantly associated with clinical/histopathological progression of pediatric IgAN.