ESPN 51th Annual Meeting

ESPN 2018


 
Clinical and histological differences between adults and children in new onset IgA nephropathy
CAMBIER ALEXANDRA 1 MARION RABANT 2 PEUCHMAUR MICHEL 1 ANNE COUDERC 1 HERTIG ALEXANDRA 3 DESCHENES GEORGES 1 SALOMON REMI 2 HOGAN JULIEN 1 ROBERT THOMAS 4

1- Pediatric Department of Nephrology and Transplantation, Assistance Publique-Hôpitaux de Paris, Hôpital Robert-Debré, Paris, France
2- Service de Pathologie, Hôpital Universitaire Hôpital Necker APHP, Paris, France
3- Department of Nephrology, Transplantation and Emergency, Assistance Publique-Hôpitaux de Paris, Hôpital Tenon, Paris, France
4- Centre de néphrologie et transplantation rénale, Assistance Publique-Hôpitaux de Marseille, Hôpital de la Conception, Marseille, France
 
Introduction:

Recent studies showed that prognosis of children IgAN could be as severe as adults but would manifest differently.We addressed this question comparing clinical and histological characteristics at diagnostic of IgAN between children and adult.

 

Material and methods:

 Data on 211 consecutive patients, including 82 children and 129 adults were reviewed. Renal biopsies were scored for Oxford classification and podocytopathic features.

Results:

Estimated glomerular filtration (eGFR) at diagnostic was lower in adults compared to children (64vs89.5 ml/min/1,73m2; p=0.0001). Serum albumin was lower in children compared to adults (3.4vs3.8g/dl, p=0.0001) while proteinuria was not different (1.8±1.6vs2.1±2.7g/g, p=0.25). Histological analysis of kidney biopsy finds higher proportion of mesangial (M1) and endocapillary (E1) proliferation in children compared to adult (M1(80.7%vs27.9%, p=0.0001); E1(71.3%vs30%, p=0.0001). Focal glomerulosclerosis/adhesion  (S1), tubular atrophy/interstitial fibrosis ≥25% (T1) and podocytopathic features (P1) were higher in adult, (S1(81.5%vs61.3%, p=0.0012), T1 (49.5%vs1.35%, p=0.0001), P1 (33.8%vs16.4%, p=0.007)). Proteinuria was associated with M1, E1 and C1 in children (M1,p=0.001; E1,p=0.0005; C1,p=0.0014) whereas proteinuria was associated with S1, P1 and T1 in adult (S1,p=0.0001; P1,p=0.0001; T1,p=0.001). In patient treated by steroid, proteinuria decreased in children (1.54(0.9–3.6) to 0.03(0.2–0.7)g/g, p<0.001) and in adult (1.31(0.77–2.2) to 0.4(0.2–1)g/g, p<0.001). eGFR remain stable in adult (41.4 to 36.9 ml/min/1.73m2) and increase significantly in children (98.6 to 109,3ml/min/1.73m2) between M0 and last follow-up.

Conclusions:

In children IgAN, proteinuria is related to glomerular proliferative lesions whereas in adult proteinuria is related to chronic lesions. Steroid would be more effectiveness on eGFR and proteinuria in children due to the steroid sensitivity of glomerular lesion.