The relationship of peritubular capillary density with glomerular volume and kidney function in living kidney donors.

BACKGROUND: Peritubular capillary rarefaction plays an important role in the progression of chronic kidney disease. Little is known about the relation between peritubular capillary density, glomerular volume and filtration rate in the healthy kidney. METHODS: In this single-center study, we included 69 living kidney donors who donated between 2005 and 2008 and had representative renal biopsies available. In all donors, glomerular filtration rate was measured using 125I-Iothalamate before donation and at five years after donation. Before donation, the increase in glomerular filtration rate after dopamine stimulation was measured. Glomerular volume and peritubular capillary density were determined in biopsies taken at the time of transplantation. Pearson's correlation coefficient and linear regression were used to assess relations between parameters. RESULTS: Mean donor age was 52 ± 11 years and mean measured glomerular filtration rate was 119 ± 22 mL/min before donation and 82 ± 15 mL/min at five years after donation. While peritubular capillary density (measured by either number of peritubular capillaries/50,000 µm2 or number of peritubular capillaries/tubule) was not associated with measured glomerular filtration rate before or after donation, number of peritubular capillaries/tubule was associated with the increase in measured glomerular filtration rate after dopamine stimulation (St.ß = 0.33, p = 0.004), and correlated positively with glomerular volume (R = 0.24, p = 0.047). Glomerular volume was associated with unstimulated measured glomerular filtration rate before donation (St.ß = 0.31, p = 0.01) and at five years (St.ß = 0.30, p = 0.01) after donation, independent of age. CONCLUSIONS: In summary, peritubular capillary density was not related to unstimulated kidney function before or after kidney donation, in contrast to glomerular volume. However, number of peritubular capillaries/tubule correlated with the increase in glomerular filtration rate after dopamine stimulation in healthy kidneys, and with glomerular volume. These findings suggest that peritubular capillary density and glomerular volume differentially affect kidney function in healthy living kidney donors.

Functional Compromise Cohort Study (FCCS): Sarcopenia is a Strong Predictor of Mortality in the Intensive Care Unit.

BACKGROUND: Functional compromise in elderly patients is considered to be a significant contributing factor in increased postoperative morbidity and mortality. It is described as a state of reduced physiologic reserves including, e.g., sarcopenia, cachexia, malnutrition and frailty with increased susceptibility to adverse health outcomes. Aim of this study was to investigate the association of sarcopenia with mortality in ICU patients. METHODS: A retrospective analysis of a total of 687 patients admitted to the ICU from January 2013 until December 2014 was performed. Indirect measurements of functional compromise in these patients were conducted. Sarcopenia was assessed using the L3 muscle index by using Osirix© on computed tomography scans. Groningen Frailty Indicator (GFI) and Short Nutritional Assessment Questionnaire (SNAQ) scores were extracted from the digital patient filing system and were used to assess frailty and nutritional status. These factors were analyzed using logistic regression analysis as predictor for in-hospital mortality and 6-month mortality, which was the primary endpoint along with other secondary outcome measures. RESULTS: Age was an independent predictor of in-hospital mortality, OR 1.043 (95% CI 1.030-1.057, p < 0.001). Analysis of sarcopenia showed OR 2.361 (95% CI 1.138-4.895, p = 0.021), for GFI OR 1.012 (95% CI 0.919-1.113, p = 0.811) and for SNAQ OR 1.262 (95% CI 1.091-1.460, p = 0.002). CONCLUSION: This study shows a promising role for the sarcopenia score as a predictor of mortality on the ICU, based upon CT imaging at L3 level and SNAQ score. Further research is necessary to test this in larger cohorts and to develop a possible instrument to predict mortality in the intensive care unit.