Muscle mass assessment by computed tomography in chronic kidney disease patients: agreement with surrogate methods.

BACKGROUND/OBJECTIVES: Patients with chronic kidney disease (CKD) are subjected to muscle wasting. Therefore, it is important to investigate surrogate methods that enable the assessment of muscle mass loss in the clinical setting. We aimed to analyze the agreement between computed tomography (CT) and surrogate methods for the assessment of muscle mass in non-dialysis CKD patients. SUBJECTS/METHODS: Cross-sectional study including 233 non-dialysis patients on CKD stages 3 to 5 (61 ± 11 years; 64% men; glomerular filtration rate 22 (14-33) mL/min/1.73 m2). The muscle mass was evaluated by CT and bioelectrical impedance, skinfold thicknesses, midarm muscle circumference (MAMC), the predictive equations of Janssen and Baumgartner and the physical examination of muscle atrophy from the subjective global assessment. RESULTS: In males, the MAMC showed the best agreement with CT as indicated by the kappa test (k = 0.57, P < 0.01), sensitivity (S = 68%), specificity (S = 89%) and accuracy (area under the curve-AUC = 0.78), followed by the Baumgartner equation (kappa = 0.46, P < 0.01; sensitivity = 60%; specificity = 87% and AUC = 0.73). In female, the Baumgartner equation showed the best agreement with CT (kappa = 0.43, P < 0.01; sensitivity = 57%; specificity = 86% and AUC = 0.71). CONCLUSIONS: The MAMC and Baumgartner equation showed the best agreement with CT for the assessment of muscle mass in non-dialysis CKD patients.

Systemic and local inflammation in peritoneal dialysis: mechanisms, biomarkers and effects on outcome.

Thanks to the technological development in peritoneal dialysis (PD) during the last three decades, the most important problem nowadays for the nephrologists is the maintenance of the long-term function of the peritoneal membrane. Although PD may exert an early survival benefit as compared with hemodialysis (HD), long-term PD is often associated with histopathological alterations in the peritoneal membrane that are linked to peritoneal ultrafiltration deficit and increased mortality risk. These alterations are closely related to the presence of a chronic activated (local and systemic) inflammatory response. PD itself may have other factors associated that could further modulate the inflammatory response, such as the bioincompatibility of dialysis solutions, fluid overload and changes in the body composition. Understanding the pathophysiology of inflammation in PD is essential for the adoption of adequate strategies to improve both membrane and patient survival.