Predictors of outcome in paediatric IgA nephropathy with regard to clinical and histopathological variables (Oxford classification).

BACKGROUND: There has been a lack of international consensus on the classification and the predictive value of the histopathology findings in IgA nephropathy (IgAN). Recently, the International IgA Nephropathy Network has developed the Oxford classification in which four histological variables with the most prognostic importance are identified (MEST score). Our objective was to validate these findings and to assess their predictive power in our cohort and to compare them to identified clinical predictors. METHODS: Ninety-nine children with a follow-up time >5 years were included and investigated with clearances of inulin or iohexol for glomerular filtration rate (GFR), proteinuria and blood pressure at biopsy and during follow-up. Biopsies (90/99) were re-evaluated and scored according to the Oxford classification. RESULTS: Eighteen patients progressed to a poor outcome [end-stage renal disease (ESRD) or GFR reduction >50%]. In the univariate analysis, we found that mesangial hypercellullarity score >0.5, presence of endocapillary hypercellularity or tubular atrophy/interstitial fibrosis of >25% were each associated with a poor outcome, and also presence of cellular or fibrocellular crescents and of global glomerulosclerosis, but segmental glomerulosclerosis did not reach statistical significance. The clinical predictors of a poor outcome were a low GFR, a high mean arterial blood pressure and a high amount of albuminuria (log Ualb/c) at time of biopsy and low GFR and a high log Ualb/c during follow-up. CONCLUSION: We found that three of the four histology lesions identified in the Oxford classification, as well as presence of crescents, were valid in predicting a poor outcome in our cohort of patients.

Renal transplantation in infants and small children.

There are still concerns about renal transplantation in small children. The aim of this study was to identify prenatal data, underlying diseases, patient and graft survival, graft function and growth in young renal transplant recipients at our center. A retrospective analysis was performed on 50 kidney transplants performed during the period 1981-2008 in children weighing <13 kg. Their median age at transplantation was 1.4 (range 0.4-3.7) years and the median weight was 9.5 (3.4-12.1) kg. The underlying diseases were congenital in 88% of the patients and acquired in 12%. Ten-year patient survival was 88% (82% before 1998 and 95% since 1998). Ten-year graft survival was 82% (75 and 95%, respectively). Graft function (glomerular filtration rate) deteriorated from a mean of 75-48 ml/min/1.73 m(2) within 10 years. There was rapid catch-up growth within the first years post-transplant, from a median height of -2.44 standard deviation score (SDS) at transplantation to -0.74 SDS after 3 years. In small children, patient and graft survival were as good as those in older children. Renal function deteriorated during the first years post-transplant but stabilized within a few years. In most children, there was a substantial improvement in growth within the first years after transplantation.

Predictors of outcome in Henoch-Schönlein nephritis.

Factors predictive of renal outcome were studied in 78 children with Henoch-Schönlein nephritis followed up for as long as 17 (mean 5.2) years. Patients with a good outcome (74%) were healthy or had microalbuminuria or mild proteinuria at the final follow-up (FU), and those with poor outcome (26%) had active renal disease or chronic kidney disease at stages IV-V. Patients with mild symptoms at onset (hematuria + or - mild proteinuria) had a poor outcome in 15% of cases versus 41% of those with severe symptoms (nephritic or nephrotic syndrome or nephritic-nephrotic picture) (p = 0.011). However, among patients with mild proteinuria at onset, 18% showed a poor prognosis; non-nephrotic proteinuria with a urine albumin/creatinine ratio at a cut-off value of >144 mg/mmol at the 1-year FU was predictive of a poor outcome. Among 59 biopsied patients, 37% of those with advanced histological findings [International Study of Kidney Disease in Children (ISKDC) stages III-V] had a poor outcome compared to none of those with mild findings (ISKDC stages I-II) (p = 0.0015). Patients with a poor outcome were older at onset, had more proteinuria, and lower glomerular filtration rate at the 1-year FU compared with patients with a good outcome. Multivariate analysis showed that proteinuria at the 1-year FU and the ISKDC grading score of the renal biopsy were the two most discriminant factors of a poor prognosis.

Treatment of severe Henoch-Schönlein and immunoglobulin A nephritis. A single center experience.

Our aim was to report the effect of two treatment regimens in 43 cases of severe Henoch-Schönlein nephritis (HSN) and immunoglobulin A nephritis (IgAN) (24 HSN, 19 IgAN). Group A, 11 HSN and 7 IgAN, 88% with an International Study of Kidney Disease in Children (ISKDC) biopsy grade > or = III and severe clinical features, were treated with corticosteroids, cyclophosphamide (CYC-P) and angiotensin-converting enzyme inhibitor/angiotensin receptor blocker (ACEi/ARB). Group B, 12 HSN and 13 IgAN, 72% with biopsy findings as above and 52% with severe clinical features, were treated with ACEi/ARB +/- corticosteroids. The outcome classification was: (a) healthy; (b) mild proteinuria, normal glomerular filtration rate (GFR); (c) active renal disease; (d) chronic renal failure. Twenty-six patients had a good outcome (a + b). The 17 children with poor outcome (c + d) had lower GFR at onset and at follow-up, higher albumin excretion at follow-up, and higher percentage of segmental glomerulosclerosis in the renal biopsy, than those with good outcome. Treatment with corticosteroids, CYC-P and ACEi/ARB was effective in increasing GFR, reducing proteinuria and decreasing the disease activity index. The proteinuria had decreased at follow-up in both groups. In group A, GFR increased and histopathological activity index declined after treatment. The outcome did not differ between groups A and B. The effects of treatment did not differ between HSN and IgAN.