Kidney Dial., Volume 4, Issue 2 (June 2024) – 5 articles

Apolipoprotein L1 (APOL1) nephropathy results from several podocyte dysfunctions involving morphological and motility changes, mitochondrial perturbations, inflammatory stress, and alterations in cation channel activity. I propose that this phenotype results from increased hydrophobicity of the APOL1 risk variants, which induces two distinct types of podocyte dysfunctions. On one hand, increased hydrophobic interactions with APOL3 cause intracellular variant isoforms to impair both APOL3 control of Golgi PI(4)P kinase-B (PI4KB) activity and APOL3 control of mitochondrial membrane fusion, triggering actomyosin reorganisation together with mitophagy and apoptosis inhibition (hit 1). On the other hand, increased hydrophobic interactions with the podocyte plasma membrane may cause the extracellular variant isoforms to activate toxic Ca²⁺ influx and K⁺ efflux by the TRPC6 and BK channels, respectively (hit 2), presumably due to APOL1-mediated cholesterol clustering in microdomains. I propose that hit 2 depends on low HDL-C/high extracellular APOL1 ratio, such as occurs in cell culture in vitro, or during type I-interferon (IFN-I)-mediated inflammation. Full article

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a complication of cardiopulmonary bypass surgery that frequently occurs in children. The increased availability of pediatric cardiac surgery leads to yearly increases in congenital heart disease (CHD) procedures performed worldwide. The number of complications, including pediatric CSA-AKI, has also increased. Children with CSA-AKI have worse postoperative periods and require more complex post-op intensive care. Thus, the timely commencement of interventions to prevent and to treat kidney injury in CHD children are one of a leading goals of pediatric cardiac intensive care. Full article

It is necessary to ensure adequate energy and protein intake in dialysis patients. However, in addition to the decline in dietary intake in older dialysis patients due to aging, the rate of anorexia is high in dialysis patients, which increases the risk of protein–energy wasting (PEW), sarcopenia, and frailty. There are many causes of anorexia in dialysis patients, including older dialysis patients, and approaches to improve the appetite of such patients have been reported; however, there has been no established approach to improve appetite adequately. Therefore, a key practical goal is to identify anorexia early and implement timely interventions before weight loss occurs. Appetite assessment tools and weight loss assessments are helpful for the screening and early identification of anorectic signs. Nutritional interventions include reducing dietary restrictions, using oral nutritional supplements, and intradialytic parenteral nutrition, as well as replenishing energy, protein, and zinc to prevent the development of nutritional disorders among older dialysis patients. Appetite assessments, early intervention, and dietary and nutritional counseling are key to improving appetite in these patients. The aging rate of dialysis patients in Japan is unprecedented globally, and I believe that this is a situation that will eventually occur in other countries as well. I discuss the factors that contribute to anorexia, especially in older dialysis patients, and Japan’s efforts to address this problem, such as the relaxation of dietary restrictions and the use of oral nutritional supplements. Full article

Background: Limited data exist on postoperative acute kidney injury (AKI) in patients who have undergone esophageal cancer surgery. The purpose of this study was to evaluate the incidence, risk factors, and consequences of postoperative acute kidney after esophagectomy. Methods: This was a retrospective cohort study. The study was conducted in a tertiary specialized cancer center in Italy. All patients undergoing elective esophageal cancer surgery between 2016 and 2021 were included in the study. AKI was defined according to Kidney Disease Improving Global Outcomes criteria (both serum creatinine and urine output), within 48 h after surgery. Preoperative and intraoperative data were registered. We also collected data concerning progression of AKI, need for renal replacement therapy, mortality, and medical (pulmonary, cardiovascular, septic) and surgical complications within 30 days from surgery, as well as length of hospital stay. Results: Incidence of postoperative AKI was 32%. The independent risk factors were body mass index and the use of an invasive surgical approach. Persistent AKI accounted for 15% of the cases and it was associated with increased risk of major cardiovascular events (odds ratio 4.14, 95% CI 1.05–15.8, p-value 0.036), pulmonary complications (OR 3.67, 95% CI 1.04–14.9, p-value 0.050), and increased length of hospital stay (AME 7.2, 0.5–13.9, p-value 0.035). Conclusions: Postoperative AKI is common after esophageal cancer surgery. BMI and a totally invasive surgical approach are independent risk factors. Persistent AKI lasting more than 48 h increased the risk for any cardiovascular or pulmonary complications, with prolonged length of hospital stay. Full article

Leptospirosis is a re-emerging zoonotic disease that has had an unprecedented impact on most health systems in the world. The spectrum of symptoms is variable and usually ranges from asymptomatic cases to severe manifestations involving multiple organ dysfunction accompanied by jaundice, hemorrhage, meningitis, and acute kidney injury that requires the need for intensive care assistance. Although early antibiotic treatment is usually effective, in severe cases, it may require renal replacement therapy, invasive mechanical ventilation, vasoactive support, and invasive hemodynamic monitoring, increasing the risk of death. In Latin America, the real burden of acute kidney injury in this condition is unknown and may be underestimated due to the rapid progression of the disease, similar to other vector zoonoses, and the low coverage of diagnostic tests in primary care, especially in rural regions. Therefore, below, we review the clinical aspects and describe the scientific, clinical, and therapeutic evidence of acute kidney injury attributed to Leptospira spp. and its relevance in patients with severe leptospirosis in Latin America. Full article