Body composition assessed by neutron activation analysis in dialysis patients

Malnutrition is prevalent in end-stage renal disease (ESRD) patients treated with hemodialysis (HD) and peritoneal dialysis (PD). In addition, there is increased incidence of morbidity in this group. Evaluation of nutritional status is important. Application of body composition in the ESRD population to evaluate body compartments and to assess nutritional health has become more common in clinical practice. Neutron activation analysis (NAA) may provide data on metabolically active tissue by quantification of total body potassium (TBK) for body cell mass and assessment of protein by total body nitrogen (TBN). This method may be able to detect changes in body composition before clinical signs of malnutrition are apparent. Ten HD (5 male and 5 female) and 10 PD patients (7 male and 3 female) were evaluated by NAA, TBK, and isotope dilution. Female PD patients had an increased total body water (TBW) and increased intracellular water compared to HD females. Albumin was lower in PD women. There was no significant difference between PD men and laboratory controls in TBW, extracellular water, and TBN. The clinical application of body composition methods for evaluation of dialysis patients by serial assessment and for development of a bedside tool needs further study.