A novel flow cytometry panel to identify prognostic markers for steroid-sensitive forms of idiopathic nephrotic syndrome in childhood.

Introduction: The clinical evolution of steroid-sensitive forms of pediatric idiopathic nephrotic syndrome (INS) is highly heterogeneous following the standard treatment with prednisone. To date, no prognostic marker has been identified to predict the severity of the disease course starting from the first episode. Methods: In this monocentric prospective cohort study we set up a reproducible and standardized flow cytometry panel using two sample tubes (one for B-cell and one for T-cell subsets) to extensively characterized the lymphocyte repertoire of INS pediatric patients. A total of 44 children with INS at disease onset were enrolled, sampled before and 3 months after standard induction therapy with prednisone and followed for 12 months to correctly classify their disease based on relapses. Age-matched controls with non immune-mediated renal diseases or with urological disorders were also enrolled. Demographical, clinical, laboratory and immunosuppressive treatment data were registered. Results: We found that children with INS at disease onset had significantly higher circulating levels of total CD19+ and specific B-cell subsets (transitional, mature-naïve, plasmablasts/plasmacells, CD19+CD27+, unswitched, switched and atypical memory B cells) and reduced circulating levels of Tregs, when compared to age-matched controls. Prednisone therapy restored most B- and T-cell alterations. When patients were subdivided based on disease relapse, relapsing patients had significantly more transitional, CD19+CD27+ memory and in particular unswitched memory B cells at disease onset, which were predictive of a higher risk of relapse in steroid-sensitive patients by logistic regression analysis, irrespective of age. In accordance, B-cell dysregulations resulted mainly associated with steroid-dependence when patients were stratified in different disease severity forms. Of note, Treg levels were reduced independently from the disease subgroup and were not completely normalized by prednisone treatment. Conclusion: We have set up a novel, reproducible, disease-specific flow cytometry panel that allows a comprehensive characterization of circulating lymphocytes. We found that, at disease onset, relapsing patients had significantly more transitional, CD19+CD27+ memory and unswitched memory B cells and those who are at higher risk of relapse had increased circulating levels of unswitched memory B cells, independently of age. This approach can allow prediction of clinical evolution, monitoring of immunosuppression and tailored treatment in different forms of INS.

Hospital Admission in the Latent versus the Active Phase of Labor: Comparison of Perinatal Outcomes.

Background: Admission in the latent phase of labor has been associated with increased risk of obstetric interventions compared to admission in the active phase. We aimed to investigate the relationship between labor phase at admission and obstetric and neonatal outcomes. Methods: A retrospective cohort study was conducted on 1005 women with uncomplicated singleton pregnancy admitted for spontaneous labor. Cesarean section rate and other perinatal outcomes were compared between women admitted in the latent phase and those admitted in the active phase. Results: Admission occurred in the active phase of labor for 331 women (32.9%) and in the latent phase for 674 (67.1%). Admission in the latent phase was more frequent in nulliparous than in multiparous (p < 0.01) and for Italian patients compared to foreigners. The incidence of caesarean section was similar between groups. Admission in the latent phase increased the likelihood of epidural analgesia (OR 3.47, 95% CI 1.96−6.14, in nulliparous, and OR 2.58, 95% CI 1.37−4.84, in multiparous) and increased the rate of augmentation of labor with oxytocin in multiparous (OR 2.87, 95% CI 1.05−7.85), without difference in neonatal outcomes. Conclusions: Admission in the latent phase is associated with more frequent use of epidural analgesia, without an increase in cesarean section or adverse neonatal outcomes.

Belimumab for the treatment of children with frequently relapsing nephrotic syndrome: the BELNEPH study.

BACKGROUND: Effectiveness of rituximab in pediatric idiopathic nephrotic syndrome suggests that B cells play a pathogenic role. We tested safety and efficacy of the B-cell-modulating agent belimumab in frequently relapsing nephrotic syndrome (FRNS). METHODS: An open-label, prospective, single-arm pilot study (EUDRACT 2017-003839-11) was designed to treat 10 children with FRNS with i.v. belimumab for 12 months. Prednisone was tapered/stopped. Safety, number of relapses, cumulative prednisone dose and B-cell subset "levels" are referred to both B cell subset and immunoglobulin. RESULTS: Five patients were enrolled, and four reached the primary 6-month endpoint. Of these, two completed the 12-month endpoint. Three patients experienced ≥2 relapses while on belimumab, requiring additional immunosuppression. Compared to the 6 months before belimumab treatment, the mean number of relapses (1.4 vs. 2, p=0.21) and the mean cumulative prednisone dose (1.86 vs. 2.62 g/m2, p=0.17) were not significantly reduced during the 6 months on belimumab. This study was terminated by the steering committee after the interim evaluation because belimumab failed to show clear benefits to counterbalance the inconvenience of monthly i.v. infusion. During follow-up, total and mature-naïve B cells decreased, while no change in memory B-cells was observed. Serum immunoglobulins remained stable. No infusion reaction was observed. CONCLUSIONS: Short-term treatment with belimumab in pediatric FRNS was well tolerated. The number of patients was too small to draw conclusions on efficacy. Nonetheless, we did not observe clear improvements. The burden of monthly in-hospital i.v. infusions outweighed potential benefits. Persistence of circulating memory B cells supports their pathogenic role in the disease. A higher resolution version of the Graphical abstract is available as Supplementary information.

An international cohort study spanning five decades assessed outcomes of nephropathic cystinosis.

Nephropathic cystinosis is a rare disease secondary to recessive mutations of the CTNS gene encoding the lysosomal cystine transporter cystinosin, causing accumulation of cystine in multiple organs. Over the years, the disease has evolved from being a fatal condition during early childhood into a treatable condition, with patients surviving into adulthood. Data on cystinosis are limited by the rarity of the disease. Here, we have investigated factors associated with kidney and growth outcome in a very large cohort of 453 patients born between 1964 and 2016 and followed in Belgium, Germany, Austria, France, Italy, Spain, The Netherlands, Turkey and United Kingdom. From the 1970s to the 1990s, the median increase in kidney survival was 9.1 years. During these years, cysteamine, a cystine-depleting agent, was introduced for the treatment of cystinosis. Significant risk factors associated with early progression to end-stage kidney disease assessed by Cox proportional multivariable analysis included delayed initiation of cysteamine therapy and higher mean leucocyte cystine levels. No significant effect on kidney function was observed for gender, pathogenic variant of the CTNS gene, and the prescription of indomethacin or renin angiotensin system blockers. Significantly improved linear growth was associated with early use of cysteamine and lower leukocyte cystine levels. Thus, our study provides strong evidence in favor of early diagnosis and optimization of cystine depletion therapy in nephropathic cystinosis.