Recently published papers: Acute kidney injury – diagnosis and treatment

When faced with the management of the patient on intensive care with acute kidney injury, the clinician has various choices to consider. The conventional therapy, where appropriate, is renal replacement therapy. This technique used to be relatively straightforward but now a relative feast of alternatives is available, not least in choice of buffer and anticoagulant. Two recent studies add to the growing body of literature concerning alternative anticoagulant regimes, and one in particular should lead to a change in practice for many of us. We also review some new studies on biomarkers in the diagnosis of acute kidney injury as well as add yet another nail in the coffin for loop diuretics in the therapy of acute kidney injury.     

Total-body bone mineral content in non-corticosteroid-treated postpubertal females with juvenile rheumatoid arthritis: frequency of osteopenia and contributing factors

OBJECTIVE: To determine the extent of low total-body bone mineral content (BMC) in non-corticosteroid-treated white postpubertal females with juvenile rheumatoid arthritis (JRA) compared with healthy age- and race-matched female controls, and to identify variables that significantly contribute to total-body BMC. METHODS: Thirty-six females with definite JRA who had never received corticosteroids and 51 healthy female controls were evaluated. All subjects had had their first menstrual period at least 2 years prior to enrollment. Total-body BMC, lumbar spine bone mineral density, and body composition were determined by dual x-ray absorptiometry. Total-body BMC Z-scores were calculated for JRA patients using data from controls. JRA patients were dichotomized into those with "normal" bone mass (total-body BMC at or above the mean or no more than 1 SD below the mean) and those with "low" bone mass (total-body BMC more than 1 SD below the mean). Comparisons of anthropometric measurements, laboratory measurements of bone metabolism, disease activity, dietary intake, and physical activity were performed. Stepwise logistic regression was utilized to determine the presence or absence of low total-body BMC and to identify associated contributing factors. RESULTS: Total-body BMC was 4.5% lower in JRA patients than in controls (mean +/- SD 2,050 +/- 379 gm versus 2,143 +/- 308 gm; P = 0.21). Twenty-five of 36 patients (69.4%) had "normal" and 11 of 36 (30.6%) had "low" total-body BMC. Comparison of JRA patients with "normal" versus those with "low" total-body BMC revealed significant differences in disease characteristics, anthropometric and physical development characteristics, laboratory measures of bone mineralization, and dietary intake. The final regression model contained only lean mass (P = 0.01), which accounted for 76.3% of the variance in total-body BMC. The odds ratio for lean mass was 0.4451 (95% confidence interval 0.2374-0.8348). CONCLUSION: In this study, approximately 30% of the subjects in a sample of postpubertal female patients with mild-to-moderate, non-corticosteroid-treated JRA had low bone mass. The predictor variable that significantly contributed to total-body BMC was lean mass, which demonstrated a protective effect of 0.56 risk reduction for low total-body BMC.     

Immunity to and incidence of measles in a population of Parisian children]

BACKGROUND. Measles remains prevalent in France despite the development of nationwide vaccination program. This study evaluates measles immunity and correlates it with active immunization. MATERIAL AND METHODS. A total of 250 (131 boys and 119 girls) French children, aged 2 to 15 years, seen as outpatients in our hospital, were studied from 1.01.90 to 1.06.91; 133 had received live measles vaccine during the 2nd year of life, the 117 others were not vaccine-protected. Evaluation included medical records, specially those concerning past-history of measles or measles-like diseases and immunizations. Measles IgG and IgM antibodies (ELISA) were looked for in all 250 children. RESULTS. 102 of the 117 children who were not vaccine-protected had a detectable antibody titer. 42 of these 102 had a history of measles, before the age of 5 years in 30, between 5 and 10 years in 9 and after the age of 10 years in 3. Only 4 of the 70 children aged over 10 years and not vaccine-protected had no detectable antibodies. 131 of the 133 actively immunized children had detectable antibodies. CONCLUSIONS. Measles is probably more frequently subclinical than was believed until now. Its relative frequency in France in children who had not received the live vaccine explains the high percentage of those aged over 10 years who had detectable antibodies and the relatively low incidence of the disease in teenagers and young adults.     

Bone mineral content in children 1 to 6 years of age. Detectable sex differences after 4 years of age

Age- and sex-specific bone mineral measures have not been available for healthy preschool children. We determined bone mineral content (BMC) and bone width in 89 children 1 to 6 years of age using direct photon absorptiometry at the one-third distal radius site. The BMC increased significantly with age, and bone width increased slightly with age. After stratification by age, male and female children had similar BMC from 1 to 4 years of age, but female children had significantly lower BMC at 5 to 6 years of age.     

Comparison of Actiwatch activity monitor and Children's Activity Rating Scale in children

PURPOSE: The Children's Activity Rating Scale (CARS) is a rating scale that is used in direct observation of physical activity in children. Direct observation is costly and tedious, and accuracy may decrease as the observation period lengthens. Recently, motion sensors have gained acceptance for assessment of physical activity. The purpose of this study was to compare 6 h of activity levels using simultaneous monitoring of preschool aged children with CARS and the Actiwatch (Mini-mitter Company Inc.) activity monitor. METHODS: A total of 40 children had 5-6 h (mean of 5.9 h) of direct observation while wearing a monitor on the waist. Simultaneous 3-min mean CARS scores and 3-min activity counts were matched for each subject. RESULTS: The range for the mean 3-min CARS scores ranged from 1.00 to 4.50. The 3-min activity counts ranged from 0 to 9,695 with a mean of 670 (median 243). The within child correlations between the 3-min CARS score and the 3-min sensor readings ranged from 0.03 to 0.92 (median of 0.74). We found the correlation coefficients were higher in those children who were more active, probably due to the larger ranges in the CARS scores. When using mixed model repeated measures, sensor readings were significantly associated with CARS (P < 0.001). CONCLUSION: Our results indicate that the 3-min CARS score correlates with 3-min activity counts, favoring the use of the activity monitors in assessing physical activity in preschool-aged children.     

Plasma amino acid and protein concentrations in infants fed human milk or a whey protein hydrolysate formula during the first month of life

The aim of the study was to compare growth parameters, biochemical indices of protein metabolism and plasma amino acid concentrations in infants fed either human milk ( n = 12) or a whey protein hydrolysate formula ( n = 13) during the first month of life. Growth and gain in skin fold thickness were similar in both groups whereas serum protein concentration was significantly decreased (57.4 ± 3.9 versus 61.2 ± 2.9 g/l) in the infants fed the whey hydrolysate formula. The discrepancies between the plasma amino acid pattern of the whey hydrolysate formula group and that of the human milk group lessened during the first month. Nevertheless, at a mean age of 33 days the plasma threonine concentration remained twice as high and the plasma tyrosine, phenylalanine and proline concentrations were Significantly lower in the whey hydrolysate formula group than in the human milk group. Thus, compared with breast-fed infants, growth and most of the biological indices of protein metabolism were satisfactory in infants fed during the first month of life on a whey protein hydrolysate formula. Nevertheless, the decrease in total plasma protein concentration needs to be confirmed in a larger cohort of infants. In addition, further research is necessary to investigate the possible ways of reducing the hyperthreoninemia and preventing other plasma amino acid disturbances since it would be desirable to obtain plasma amino acid levels similar to those of breast-fed infants.     

Red blood cell fatty acid composition in low-birth-weight infants fed either human milk or formula during the first months of life

The fatty acid composition of red blood cell (RBC) phospholipids in low-birth-weight infants was determined immediately after delivery and during the first 3 months of life. In the first study, infants were fed either human milk or two formulas with different fatty acid compositions but no long chain polyunsaturated fatty acids (LCPUFA). Both groups of formula-fed infants had significantly lower levels of docosahexaenoic acid (DHA) in RBC phospholipids compared with breast-fed infants. RBC phospholipid DHA was similar in the two formula groups at all ages. In the second study, infants received either a non-supplemented or a LCPUFA-supplemented formula. DHA remained stable in RBC phospholipids of infants supplemented with LCPUFA, whereas DHA decreased in RBC phospholipids of unsupplemented infants. These results confirm that adding DHA to formulas is more effective than increasing 18:3 n-3 content, in maintaining RBC phospholipid DHA levels.