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Sclerostin is a marker of low-turnover bone disease in end stage renal disease patients. The aim of this study was to evaluate serum sclerostin in uremic patients, analyzing its behavior during a single hemodialysis session. Twenty-one adult patients on intermittent hemodialysis treatment were enrolled. Acetate Free Bio-filtration (AFB) was the technique employed. Uremic patients were characterized by higher levels of serum sclerostin when compared with values observed in healthy subjects. Sclerostin assessed in pre-dialysis samples was 1.4 ± 1.02 ng/mL, whereas, in post dialysis samples, a reduction of sclerostin values was observed (0.8 ± 0.6 ng/mL; p: 0.008). Sclerostin correlated with parameters of dialysis adequacy, such as creatinine levels and Kt/V values, and it was significantly associated with atherosclerotic disease. Receiver operating characteristics analysis revealed a good diagnostic profile in identifying atherosclerotic disease. Sclerostin, a full dialyzable substance during AFB dialysis, is closely associated with atherosclerotic disease. Its reduction obtained through AFB could represent a defensive mechanism, improving vascular disease and renal osteodystrophy.

Metformin, belonging to a class of drugs called biguanides, is the recommended first-line treatment for overweight patients with type 2 diabetes mellitus. It has multiple mechanisms of action, such as reduction of gluconeogenesis, increases peripheral uptake of glucose, and decreases fatty acid oxidation. However, a potential serious complication, defined metformin-associated lactic acidosis (MALA), is related to increased plasma lactate levels, linked to an elevated plasma metformin concentrations and/or a coexistent condition altering lactate production or clearance. The mortality rate for MALA approaches 50% and metformin has been contraindicated in moderate and severe renal impairment, to minimize its potential toxic levels. Nevertheless, metformin prescription or administration, despite the presence of contraindications or precipitating factors for MALA, was a common topic highlighted in all reviewed papers. Routine assessment of metformin plasma concentration is not easily available in all laboratories, but plasma metformin concentrations measured in the emergency room could ensure the correct diagnosis, eliminating metformin as the cause of lactic acidosis if low plasma levels occurred. Renal replacement therapies have been successfully employed to achieve the correction of metabolic acidosis and rapidly remove metformin and lactate, but the optimal treatment modality for MALA is still controversial.

Peritonitis, the most important limitation of peritoneal dialysis (PD), could be detected by biomarkers in dialysate effluent, representing a noninvasive method to indirectly assess the peritoneum status. The aim of our study was to test high mobility group box 1 (HMGB1) in PD patients, evaluating its role as precocious marker of peritoneum damage during peritonitis. Transforming growth factor (TGF)-β was correlated with peritoneal transport characteristics.Six patients, treated by ambulatory PD, were enrolled. Samples were collected at the onset of peritonitis (T1) and every day until its resolution (T-end). Serum (s) and peritoneal (p) white blood cell (WBC) count was also evaluated. Peritoneal Equilibration Test evaluated the filter activity of peritoneum.In patients with acute peritonitis, the highest serum and peritoneal HMGB1 values (64 ± 3.6 and 70 ± 5.3 ng/mL, respectively) were assessed, with a progressive decrease of their levels at the resolution time (T-end: sHMGB1:36 ± 2.5; pHMGB1:30.5 ± 7.0 ng/mL). While no differences of sWBC and pWBC were observed between baseline and T-end values, pHMGB1 levels remained higher at T-end than those observed at T0 (pHMGB1:30.5 ± 7.0 versus 6.9 ± 3.6; p 0.0001). TGF-β levels were higher in patients with low peritoneal permeability than in medium or high transporter patients (81 ± 15.5 versus 24.3 ± 7.5 pg/mL; p = 0.01). An inverse correlation was found between TGF-β levels and dialysate/plasmatic creatinine values (r = -0.83; p = 0.03).HMGB1 represents a useful biomarker for peritoneum evaluation in PD patients. A prognostic role of this alarmin, as a marker of response to therapy, could be hypothesized. TGF-β could predict the peritoneal transport status and dialysis technique adequacy.

Joubert syndrome (JBTS) is a rare autosomal recessive disorder with an underestimated prevalence due to lack of recognition of clinical signs or failure to diagnose this pathology. JBTS is clinically heterogeneous, and it is characterized by a multiple organ involvement predominantly due to the requirement for Joubert gene function in several tissues. Renal disease affects approximately 30% of patients with JBTS, presenting itself in most cases as nephronophthisis (NPHP), a structural tubulo-interstitial disorder characterized by thickened basal membrane of the tubular epithelium and progressive interstitial fibrosis, associated with cysts at the cortico-medullary junction. We propose three cases concerning three patients with JBTS having different years of illness and degrees of renal impairment, evaluating the parameters of renal function at the time of genetic diagnosis and seen after a follow-up of 7 years. We measured neutrophil gelatinase-associated lipocalin (NGAL), considered as an excellent predictor of kidney injury, to evaluate whether this biomarker might be an early biomarker for JBTS-related kidney disease. NGAL was high in all three cases, but with different levels, indicating a tubular suffering typical of this syndrome, with dissimilar severity in the analyzed subjects. NGAL could represent an early indicator of renal damage useful to start an intensive nephrologic follow-up.

Approximately one-third of all dialysis patients have mild to moderate malnutrition, while 6-8% have severe malnutrition, which is associated with increased morbidity and mortality rates and numerous pre-existing factors directly correlated with, or existing prior to, replacement hemodialysis. However, moderate to severe malnutrition (present in 10-30% of dialysis patients) is a prevalent cause of death among the elderly. Many of these patients have a particularly unstable cardiovascular and metabolic status that, independent of any underlying uremia and/or dialysis, impacts negatively on both their quality of life and clinical status. Moreover, their condition is often further exacerbated by dialysis itself, with its acute (e.g., hypotension and sensorial alterations) and chronic complications, including an exacerbation of malnutrition and systemic vascular disease. Malnutrition can occur secondary not only to erroneous dietary choices or uremia, but it may also depend on the patient's level of tolerance to dialysis and on the dialysis modality. Despite the improvements made to dialysis techniques, the nutritional condition of elderly patients on dialysis for chronic renal failure remains a cause for concern. In this patient category, it is therefore mandatory to ensure the daily supervision of nutritional status and early control when the first signs of malnutrition appear.

Uremic patients are characterized by a "pro-arrhythmic substrate." Arrhythmia appearance during hemodialysis (HD) is an unexpected event with a high incidence of mortality and morbidity and difficult to record in patients repeatedly checked using electrocardiogram (ECG). Furthermore the carrying out of this important examination by classical devices during HD is uncomfortable and sometimes stressful for the patient. It may be very useful to monitor the patient's cardiac activity during the whole HD session. We tried to overcome these difficulties using Whealthy(®) (Wearable Health Care System), a wearable system in a T-shirt composed of conductors and piezoresistive materials, integrated to form fibers and threads connected to tissular sensors, electrodes, and connectors. ECG and pneumographic impedance signals are acquired by the electrodes in the tissue, and the data are registered by a small computer and transmitted via GPRS or Bluetooth.