[An overview on acute kidney injury in COVID-19].

SARS-CoV-2 infection is responsible for the coronavirus disease 2019 (COVID-19). In the complex scenario of COVID-19, it is also possible to find patients with renal damage. The pathogenesis is multifactorial and not unique, and the clinical presentation may include urinary alterations, such as proteinuria and hematuria, accompanied with reduced renal function, or not. Acute kidney injury (AKI) is not uncommon, especially among critically ill patients hospitalized in intensive care unit. AKI is a negative prognostic factor and is associated with high in-hospital mortality. An early diagnosis of AKI and the assessment of any risk factors allow the nephrologist to implement appropriate therapeutic strategies, such as pharmacological or extracorporeal support. Still, mortality in patients with AKI during COVID-19 remains high. COVID-19 AKI is a quickly evolving field of study.

[Acute kidney failure in differentiation syndrome: a possible complication during therapy with differentiating agents for acute promyelocytic leukemia. A case report].

Differentiation syndrome (DS), previously known as retinoic acid syndrome or ATRA (all-trans retinoic acid) or ATO (arsenic trioxide) syndrome, is a life-threatening complication of the therapy with differentiating agents in patients with acute promyelocytic leukemia (APL). The latter is a rare subtype of acute myeloid leukemia and represents a hematological emergency. The clinical manifestations of DS, after induction therapy with differentiating agents, include unexplained fever, acute respiratory distress with interstitial pulmonary infiltrates, unexplained hypotension, peripheral edema, congestive heart failure and acute renal failure. The therapy is based on early intravenous administration of high-dose dexamethasone, in order to counteract the cytokine storm responsible for the DS. Among the supportive measures for the management of DS, furosemide (in 87% of patients) and dialysis (12% of patients) are used to manage acute renal failure, peripheral and pulmonary edema. We describe a case of acute renal failure, treated with haemodialysis, in a young patient with APL and an early and severe DS after induction therapy. This is a rare condition, not well known among nephrologists, where early recognition and treatment are crucial for the prognosis.

Acute effects of very-low-protein diet on FGF23 levels: a randomized study.

BACKGROUND AND OBJECTIVES: High levels of fibroblast growth factor 23 are associated with mortality, CKD progression, and calcification in CKD patients. The aim of this pilot study is to assess whether a very-low-protein diet (0.3 g/kg per day) with a consequent low intake of phosphorus would reduce fibroblast growth factor 23 compared with a low-protein diet (0.6 g/kg per day) in CKD patients not yet on dialysis. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A prospective, randomized, controlled crossover study was performed in which 32 patients were randomized into two groups. Group A (16 patients) received a very-low-protein diet (0.3 g/kg body wt per day) supplemented with ketoanalogues during the first week and a low-protein diet during the second week, and group B (16 patients) received a low-protein diet during the first week and a very-low-protein diet during the second week. Fibroblast growth factor 23, seric, and urinary phosphate levels were measured at baseline and the end of each study period. RESULTS: After only 1 week of the very-low-protein diet, reductions in fibroblast growth factor 23 levels (33.5%), serum phosphate (12%), and urinary phosphate (34%) with the very-low-protein diet compared with the low-protein diet were observed. Serum and urinary phosphate levels and protein intake were significant determinants of fibroblast growth factor 23 (95% confidence interval=1.04-1.19, 1.12-1.37, and 1.51-2.23, respectively). CONCLUSIONS: A very-low-protein diet supplemented with ketoanalogues reduced fibroblast growth factor 23 levels in CKD patients not yet on dialysis.

Zaleplon improves sleep quality in maintenance hemodialysis patients.

BACKGROUND/AIM: A recent survey has shown that insomnia is still a very common problem in maintenance hemodialysis (MHD) patients. The aim of the present study was to test the effects of zaleplon (ZAL), a new nonbenzodiazepine hypnotic drug, on the sleep quality of MHD patients with insomnia. METHODS: The sleep quality was assessed by the Pittsburgh questionnaire in 10 patients (6 males/4 females) with insomnia on MHD; these patients underwent a randomized double-blind crossover study versus placebo (PLA). The main exclusion criterion was the presence of any possible cause of insomnia related to other concurrent diseases. RESULTS: Treatment with ZAL significantly improved the total score of sleep quality (p < 0.03 vs. PLA). The analysis of the single components revealed that treatment with ZAL was associated with a higher subjective sleep quality (p < 0.01 vs. PLA) and a reduced sleep latency (p < 0.01 vs. PLA). The duration of sleep was not modified by ZAL, whereas a significant improvement was detected in habitual sleep efficacy (p < 0.05 vs. PLA). No peculiar side effect was recorded on ZAL. Blood parameters did not change, nor were differences recorded in the dialysis parameters (body weight gain, blood pressure) throughout the study. CONCLUSIONS: This study suggests that ZAL has a positive effect on the sleep quality in MHD patients. The absence of side effects and its pharmacodynamic properties make ZAL a useful drug in uremic patients.