Chapters authored
Fluid Overload in Peritoneal Dialysis
The prevalence of end-stage renal disease (ESRD) has increased globally to 10% due to diabetes mellitus, hypertension, and stroke. When chronic kidney disease (CKD) maintenance therapy fails, patients require renal replacement therapy (RRT) to survive, such as peritoneal dialysis (PD), hemodialysis, and renal transplantation. The most common therapy in Mexico is PD because it is a feasible, low-cost, and easy-to-perform procedure; however, fluid overload is a frequent condition in patients with this RRT modality. The usual adverse comorbidities in patients with PD are cardiovascular diseases (CVD) associated to atherosclerosis, uremia, inflammation, and oxidative stress. Fluid overload is intimately associated to hypertension, left ventricular hypertrophy, heart failure, and worsening of kidney failure, leading to increased hospital admissions, higher cardiovascular mortality, and reduced life expectancy. Two main pathologies are involved in the deterioration of both heart and kidney functions, namely, cardiorenal syndrome and uremic cardiomyopathy. Along with these phenomena, patients in PD with rapid peritoneal transport have reduced ultrafiltration, increased glucose absorption, and albumin loss in the dialysate, which lead to overhydration, hypertension, dyslipidemia, and malnutrition. This review focuses on the clinical, physiological, and biochemical mechanisms involved in fluid overload of patients with CKD undergoing PD.
Part of the book: Chronic Kidney Disease
Vascular Calcification and Oxidative DNA Damage as Nontraditional Cardiovascular Risk Factors in Chronic Renal Disease
The number of CKD sufferers that require renal replacement techniques (RRTs) is increasing. The severity of cardiovascular disease (CVD) is disproportionate in these kinds of patients and contributes considerably to mortality in CKD patients. We evaluated the association between oxidative DNA damage, antioxidant activity and vascular calcification (VC) in CKD. An analytical cross-sectional study was performed. Two simple plaques were taken for each patient (pelvis-hip, and hands-wrists). The presence of VC was scored as presence (1) and absence (0). Oxidative stress was determined by activity of catalase, superoxide dismutase (SOD) and oxidative DNA damage by determination of 8-OHdG marker. Eighty-one patients were included. The RRT type was similar for hemodialysis (HD) and peritoneal dialysis (PD). Thirty-eight patients (47%) presented VC (p < 0.01); in 61%, the VC was severe (≥3 points). VC prevalence in women was significantly higher, (67%) (p < 0.001), and (29%) men. Sixty four percent of the patients submitted to HD presented VC and 27% to PD (p < 0.001). The activity of the catalase enzyme was significantly decreased in CKD vs. the healthy control (HC) (p < 0.0001). The oxidative DNA damage in CKD was greater vs. HC (p < 0.0001). In conclusion, the VC was frequent (47%) in CKD, and decreased catalase activity and greater oxidative DNA damage.
Part of the book: Free Radicals, Antioxidants and Diseases
Diagnosis, Prevention, and Treatment of Protein-Energy Wasting in Peritoneal Dialysis
Protein-energy wasting (PEW) is highly prevalent in peritoneal dialysis (PD) patients and is associated with mortality. Reduced protein and energy intake, comorbidity conditions, endocrine disorders, increased inflammatory cytokines, uremic toxins, metabolic acidosis, oxidative stress, nutrient losses into dialysate, continuous absorption of glucose from PD solutions, abdominal fullness induced by the dialysate, and peritonitis contribute to PEW. Assessment of nutritional status for the detection and management of PEW includes the PEW definition criteria, subjective global assessment (SGA), malnutrition-inflammation score (MIS), and geriatric nutritional risk index (GNRI). Diverse factors can affect nutritional and metabolic status in these patients so multiple strategies may be required to prevent or reverse PEW. Preventive measures include continuous nutritional counseling, optimizing dietary nutrient intake, and managing comorbidities. To treat PEW, the following may be used: administration of oral, intraperitoneal, enteral, or parenteral nutritional supplementation and adjunct therapies such as anabolic agents, appetite stimulants, anti-inflammatory interventions, and exercise. Diagnosis, prevention, and treatment of PEW in PD patients may favorably impact the prognosis and course of the disease.
Part of the book: Evolving Strategies in Peritoneal Dialysis
Immunosuppressive Minimization Strategies in Kidney Transplantation
The long-term graft survival in renal transplantation results is still controversial, the toxicity and adverse reactions of the immunosuppressive drugs are implicated, as well as cellular and humoral antigen-specific immune mechanisms; therefore, different strategies for adapting immunosuppression are used to reduce the complications associated with the use of these drugs. Calcineurin inhibitors (CNI) require an adequate dose-dependent concentration leading to the appearance of drug-related adverse reactions. The variability in the required dose of CNI leads to minimization strategies that do not result in a higher acute rejection (AR) incidence when compared to other immunosuppressive agents. Early steroid withdrawal is another strategy, although with an increase in AR, but without an impact on the function and survival of the renal graft. The reduction of mycophenolate mofetil to 1.5 g/day seems to be a therapeutic option, decreasing the infectious, hematological and gastrointestinal adverse reactions. Finally, alemtuzumab, bortezomib, belatacept and cellular therapies are in the search for the new treatments, whose premise is the induction of donor-specific nonresponse in the context of operational tolerance or mixed chimerism. The use of adapted and adequate immunosuppression has led to variable results and some are very encouraging; however, they must be validated with experimental studies.
Part of the book: Organ Donation and Transplantation