Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides are rare systemic diseases that usually occur in adulthood. They comprise granulomatosis with polyangiitis (GPA, Wegener’s), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (EGPA, Churg-Strauss syndrome). Their clinical presentation is often heterogeneous, with frequent involvement of the respiratory tract, the kidney, the skin and the joints. ANCA-associated vasculitis is rare in childhood but North-American and European cohort studies performed during the last decade have clarified their phenotype, patterns of renal involvement and their prognostic implications, and outcome. Herein, we review the main clinical and therapeutic aspects of childhood-onset ANCA-associated vasculitis, and provide preliminary data on demographic characteristics and organ manifestations of an Italian multicentre cohort.

Overall, the toxicity of anti-CD20 monoclonal antibodies was limited to post-infusion side effects in children with more complex disease. The relatively safe profile of anti-CD20 antibodies supports their use as steroid-sparing agents in children with INS.

Background. A renewed interest for activity and chronicity indices as predictors of lupus nephritis (LN) outcome has emerged. Revised National Institutes of Health (NIH) activity and chronicity indices have been proposed to classify LN lesions but should be validated by future studies. Aims of this study: i) to detect the histological features associated with the development of Kidney Function Impairment (KFI); ii) to identify the best clinical-histological model to predict KFI at time of kidney biopsy. Methods. LN patients with kidney biopsy containing >10 glomeruli per specimen were admitted to the study. Univariate and multivariate logistic regression and Cox proportional hazards model were used to investigate whether activity and chronicity indices could predict KFI development. Results. Among 203 LN participants followed for 14 years, correlations were found between activity index and its components and clinical-laboratory signs of active LN at baseline. Chronicity index was correlated with serum creatinine. Thus, serum creatinine was significantly and directly correlated with both activity and chronicity indexes. At multivariate analysis glomerular sclerosis (OR:3.0478, CI:1.173-7.91, P=0.022) and fibrous crescents (OR:6.8352, CI:3.218-14.519, P<0.001) associated with either moderate/severe tubular atrophy (OR:3.1697, CI:1.042-9.643, P=0.0421), or with interstitial fibrosis (OR:2.361, CI:1.047-5.322, P=0.0383) predicted KFI. Considering both clinical and histological features, serum creatinine (OR:1.677; 1.311-2.145; P<0.001), arterial hypertension (OR:4.641, CI: 1.902-11.324, P<0.001), glomerular sclerosis (OR:2.123, CI:1.001-4.503, P=0.049), and fibrous crescents (OR:5.182, CI: 2.433-11.037, P<0.001) independently predicted KFI. Older age (P<0.001) and longer delay between clinical onset of LN and kidney biopsy (P<0.001) were significantly correlated with baseline chronicity index. Conclusions. Chronicity index and its components, but not activity index, were significantly associated with an impairment of kidney function. The Cox model showed that serum creatinine, arterial hypertension, chronic glomerular lesions and delay in kidney biopsy predicted KFI. These data reinforce the importance of timely kidney biopsy in LN.

Purpose To evaluate the post-coronavirus disease-19 (COVID-19) outcome of thyroid function in patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2)-related thyrotoxicosis. Methods This was a single-center prospective study involving 29 patients (11 females, 18 males; median age 64 years, range: 43-85) with thyrotoxicosis diagnosed after hospitalization for COVID-19 and then followed-up for a median period of 90 days (range: 30-120) after hospital discharge. At follow-up, patients were evaluated for serum thyrotropin (TSH), freethyroxine (FT4), free-triiodiothyronine (FT3), TSH receptor antibodies (TRAb), thyroglobulin antibodies (TgAb), thyroperoxidase antibodies (TPOAb) and ultrasonographic thyroid structure. Results After recovery of COVID-19, serum TSH values significantly increased (P < 0.001) and FT4 values significantly decreased (P = 0.001), without significant change in serum FT3 (P = 0.572). At follow-up, 28 subjects (96.6%) became euthyroid whereas overt hypothyroidism developed in one case. At the ultrasound evaluation of thyroid gland, hypoecogenicity was found in 10 patients (34.5%) and in these cases serum TSH values tended to be higher than those without thyroid hypoecogenity (P = 0.066). All subjects resulted to be negative for TgAb, TPOAb and TRAb. Conclusion In a short-term follow-up, thyroid function spontaneously normalized in most subjects with SARS-CoV-2-related thyrotoxicosis. However, thyroid hypoecogenicity was found in a remarkable number of them and future longer-term studies are needed to clarify whether this ultrasonographic alteration may predispose to develop late-onset thyroid dysfunction.

Background Although rapidly progressive glomerulonephritis is the main renal phenotype of anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV), slow renal disease progression is sometimes observed. These forms have been rarely discussed; we analysed their prevalence, clinico-pathological characteristics and outcome. Methods We screened patients with microscopic  polyangiitis (MPA) and granulomatosis with polyangiitis followed at seven referral centres and selected those with estimated glomerular filtration rate (eGFR) reduction &lt;50% over a 6-month period preceding diagnosis. Data regarding patient features and response to treatment were retrieved. Results Of 856 patients, 41 (5%) had slowly progressive renal AAV. All had MPA and all but one was P-ANCA/myeloperoxidase (MPO) ANCA-positive. At diagnosis, the median age was 70 years [interquartile range (IQR) 64–78] and extra-renal manifestations were absent or subclinical (interstitial lung lesions in 10, 24%). The median (IQR) eGFR was 23 mL/min/1.73 m2 (15–35); six patients (15%) had started renal replacement therapy (RRT). All had proteinuria (median 1180 mg/24 h, IQR 670–2600) and micro-haematuria. Main histologic findings were extracapillary proliferation at chronic stages and glomerulosclerosis; following Berden’s classification, 6/28 biopsies (21%) were ‘focal’, 1/28 (4%) ‘crescentic’, 9/28 (32%) ‘mixed’ and 12/28 (43%) ‘sclerotic’. At last follow-up (median 32 months, IQR 12–52), 20/34 patients (59%) treated with immunosuppression had eGFR improvement &gt;25% as compared with diagnosis, while 4/34 (12%) had started RRT. Conclusions AAV may present with slow renal disease progression; this subset is hallmarked by advanced age at diagnosis, positive MPO-ANCA, subclinical interstitial lung lesions and chronic damage at kidney biopsy. Partial renal recovery may occur following immunosuppression.

Background. In this study we investigated the relevance of myostatin and Hepatocyte Growth Factor (HGF) in patients undergoing hemodialysis HD and the influence of different HD modalities on their levels. Methods. We performed a prospective crossover study in which HD patients were randomized to undergo 3-month treatment periods with bicarbonate hemodialysis (BHD) followed by online hemodiafiltration (HDF). Clinical data, laboratory parameters, and myostatin and HGF serum levels were collected and compared. Results. Ten patients and six controls (C) were evaluated. In any experimental condition myostatin and HGF levels were higher in HD than in C. At enrollment and after BHD there were not significant correlations, whereas at the end of the HDF treatment period myostatin and HGF were inversely correlated (r  −0.65, p < 0.05), myostatin serum levels inversely correlated with transferrin (r  −0.73, p < 0.05), and HGF levels that resulted positively correlated with BMI (r 0.67, p < 0.05). Moving from BHD to HDF, clinical and laboratory parameters were unchanged, as well as serum HGF, whereas myostatin levels significantly decreased (6.3 ± 4.1 versus 4.3 ± 3.1 ng/ml, p < 0.05). Conclusions. Modulation of myostatin levels and myostatin/HGF balance by the use of different HD modalities might represent a novel approach to the prevention and treatment of HD-related muscle wasting syndrome.

<b><i>Background:</i></b> Patients affected by chronic kidney disease are at a risk of cardiovascular morbidity and mortality. Body fluids unbalance is one of the main characteristics of this condition, as fluid overload is highly prevalent in patients affected by the cardiorenal syndrome. <b><i>Summary:</i></b> We describe the state of the art and new insights into body volume evaluation. The mechanisms behind fluid balance are often complex, mainly because of the interplay of multiple regulatory systems. Consequently, its management may be challenging in clinical practice and even more so out-of-hospital. Availability of novel technologies offer new opportunities to improve the quality of care and patients’ outcome. Development and validation of new technologies could provide new tools to reduce costs for the healthcare system, promote personalized medicine, and boost home care. Due to the current COVID-19 pandemic, a proper monitoring of chronic patients suffering from fluid unbalances is extremely relevant. <b><i>Key Message:</i></b> We discuss the main mechanisms responsible for fluid overload in different clinical contexts, including hemodialysis, peritoneal dialysis, and heart failure, emphasizing the potential impact provided by the implementation of the new technologies.

Background and objectives. Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis is extremely rare in children. We report the clinico-pathological features, long-term outcomes, and prognostic factors of a large paediatric cohort of patients with ANCA-associated kidney vasculitis. Design, setting, participants, and measurements. This retrospective study included 85 consecutive patients with kidney biopsy-proven ANCA-associated vasculitis followed at tertiary referral centres in Italy and Canada. Kidney biopsies were categorised as focal, crescentic, sclerotic or mixed following Berden's classification. The prognostic significance of baseline clinical, laboratory and histological findings was analysed with respect to kidney failure or chronic kidney disease (CKD) 3-5/kidney failure. Results. Fifty-three patients had microscopic polyangiitis (62%) and 32 granulomatosis with polyangiitis (38%). Rapidly progressive glomerulonephritis was the most frequent presentation (39%); one third of the patients also had nephrotic-range proteinuria. Kidney biopsies were classified as focal in 21% of the patients, crescentic in 51%, sclerotic in 15% and mixed in 13%. Remission-induction therapies included cyclophosphamide in 78% of cases. Twenty-five patients (29%) reached kidney failure. The median time to kidney failure or last follow-up was 35 months (6-89) in the whole cohort, and 73 months (24-109) among the patients who did not reach this outcome. Cases with sclerotic histology showed significantly shorter kidney survival [HR 11.80 (95% CI 2.49-55.99)] and CKD 3-5-free survival [HR 8.88 (95% CI 2.43-32.48)] as compared with focal/mixed ones. Baseline eGFR, low serum albumin, hypertension, central nervous system complications and sclerotic histology, which reflected severe kidney involvement, were associated with both kidney failure or CKD stage 3-5/kidney failure at unadjusted analysis; no independent prognostic factors emerged at multivariate analysis. Conclusions. Children with ANCA-associated kidney vasculitis often have aggressive presentation; one-third of them progress to kidney failure and usually do so early during the follow-up. A severe renal presentation is associated with the development of CKD or kidney failure.