Outcome of immunosuppression in children with IgA vasculitis-related nephritis

BACKGROUND AND HYPOTHESIS

IgA vasculitis with nephritis (IgAVN) is the most common vasculitis in children. Treatment recommendations are, due to a lack of evidence, based on expert opinion resulting in variation. The aim of this study was to describe clinical presentation, treatment and outcome of an extremely large cohort of children with biopsy proven IgAVN to identify prognostic risk factors and signals of treatment efficacy.

METHODS

Retrospective data were collected on 1148 children with biopsy proven IgAVN between 2005 and 2019 from 41 international paediatric nephrology centres across 25 countries and analyzed using multivariate analysis. The primary outcome was estimated glomerular filtration rate (eGFR) and persistent proteinuria at last follow up.

RESULTS

The median follow up was 3.7 years (IQR 2-6.2). At last follow up, 29% of patients had an eGFR < 90 ml/min/1.73m2, 36% had proteinuria and 3% had chronic kidney disease stage 4-5. Older age, lower eGFR at onset, hypertension and histological features of tubular atrophy and segmental sclerosis were predictors of poor outcome. There was no evidence to support any specific second line immunosuppressive regimen to be superior to others, even when further analysing subgroups of children with reduced kidney function, nephrotic syndrome or hypoalbuminemia at onset. Delayed start of immunosuppressive treatment was associated with a lower eGFR at last follow up.

CONCLUSION

In this large retrospective cohort, key features associated with disease outcome are highlighted. Importantly there was no evidence to support that any specific immunosuppressive treatments were superior to others. Further discovery science and well-conducted clinical trials are needed to define accurate treatment and improve outcomes of IgAVN.

MEFV gene mutations in children with Henoch-Schönlein purpura and their correlations-do mutations matter?

OBJECTIVE

To explore the frequency of MEFV gene mutations in children with Henoch-Schönlein purpura who had no prior familial Mediterranean fever diagnosis and to evaluate the association of MEFV mutations with the clinical and laboratory features of Henoch-Schönlein purpura.

METHODS

Data of 1120 patients diagnosed with Henoch-Schönlein purpura were reviewed retrospectively. The spectrum and degree of organ involvement and acute phase reactant levels were documented for each patient. Blood for MEFV gene mutation analysis was obtained either at the time of the Henoch-Schönlein purpura diagnosis or during follow-up visits. Pathological specimens of patients who underwent biopsy (renal/skin) were evaluated with special consideration for immunofluorescent examinations.

RESULTS

Two hundred and thirty-eight (21.3%) patients were found to have one of the MEFV mutations in which exon 10 mutations were the most common (16.7%). Abdominal pain, joint involvement, scrotal involvement, and relapse were more frequent, and acute-phase reactant levels were significantly high in patients with MEFV mutations. More severe characteristics were observed in the presence of homozygous exon 10 mutations. There was no significant association between exon 2 variants and clinical course of Henoch-Schönlein purpura. Patients carrying MEFV mutations did not have significantly higher levels of IgA deposits in the biopsy materials.

CONCLUSION

Henoch-Schönlein purpura in patients with homozygous exon 10 MEFV mutations seems to be more severe than that in patients carrying other mutations. In patients with exon 10 MEFV mutations, Henoch-Schönlein purpura might be considered as an associated presentation of familial Mediterranean fever rather than a separate clinical entity. Key points • p.M694V mutation is more common in Henoch-Schönlein purpura than in the general population. • p.E148Q variants have no impact on clinical symptoms and laboratory findings in Henoch-Schönlein purpura patients. • The majority of Henoch-Schönlein purpura patients with familial Mediterranean fever have no IgA deposits. • Henoch-Schönlein purpura in familial Mediterranean fever patients may be considered as an integral clinical feature of familial Mediterranean fever.

Value of renal pelvic diameter and urinary tract dilation classification in the prediction of urinary tract anomaly

BACKGROUND

The aim of this study was to identify the cut-offs of postnatal anteroposterior renal pelvic diameter (APRPD), according to the urinary tract dilation (UTD) classification system, to identify the predictors of final diagnosis of UTD and the need for surgery.

METHODS

A total of 260 infants (336 renal units) with prenatally detected UTD were prospectively evaluated on serial ultrasonography by the same radiologist. Additional voiding cystourethrography and scintigraphy was done according to the clinical algorithm.

RESULTS

Prenatal and postnatal APRPD in patients with transient dilation were significantly lower than in those with urinary tract anomalies (UTA). On follow up, the slope of decrease in APRPD was significantly higher in transient dilation compared with UTA. APRPD 10 mm at first-month ultrasonography, predicted UTA with a sensitivity of 83.1%, and specificity of 71.1%. On multivariate analysis the likelihood of surgical intervention and final diagnosis were predicted independently by the UTD system risk group.

CONCLUSIONS

Careful ultrasonography evaluation can avoid unnecessary testing in patients with transient or clinically insignificant dilation. The UTD classification system is valid for evaluation of postnatal hydronephrosis and is reliable in predicting the need for surgical intervention.