Factors affecting prepubertal growth in homozygous sickle cell disease

OBJECTIVE: To investigate the role of haematological indices, socioeconomic status, and morbidity in prepubertal growth in homozygous sickle cell (SS) disease. METHOD: Height, weight, and haematology were serially recorded in a cohort study of 315 children with SS disease from birth to 9 years at the sickle cell clinic of the University Hospital of the West Indies, Kingston, Jamaica. RESULTS: Height increment between 3 and 9 years correlated positively with total haemoglobin at age 7 years in boys but not girls. Attained height and weight at age 7 years correlated positively with haemoglobin and fetal haemoglobin in boys but not girls. Only the correlation between haemoglobin and weight showed a significant gender difference. Partial correlation analysis suggested that the effect of haemoglobin was accounted for by the effect of fetal haemolglobin and further analysis indicated that height correlated with F reticulocyte count (a measure of fetal haemoglobin production) in both sexes but not with the ratio of F cells to F reticulocytes (a measure of F cell enrichment). Growth was not significantly related to mean red cell volume, proportional reticulocyte count, alpha thalassaemia, socioeconomic status, or morbidity. CONCLUSION: A high concentration of fetal haemoglobin in boys with SS disease is associated with greater linear growth. It is postulated that in boys, low concentrations of fetal haemoglobin increase haemolysis and hence metabolic requirements for erythropoiesis, putting them at greater risk of poor growth. Differences in the relationship of haematology and growth between boys and girls with SS disease dictate that future analyses of growth take gender into account.     

Standards for total body fat and fat-free mass in infants

Data on body composition in conjunction with reference centiles are helpful in identifying the severity of growth and nutritional disorders in infancy and for evaluating the adequacy of treatment given during this important period of rapid growth. Total body fat (TBF) and fat-free mass (FFM) were estimated from total body electrical conductivity (TBEC) measurements in 423 healthy term Caucasian infants, aged 14-379 days. Cross sectional age, weight, and length related centile standards are presented for TBF and FFM. Centiles were calculated using Altman's method, based on polynomial regression and modelling of the residual variation. The TBF percentage steeply increased during the first half year of life, and slowly declined beyond this age. Various simple TBEC derived anthropometric prediction equations for TBF and FFM are available to be used in conjunction with these standards. Regression equations for the P50 and the residual SD, depending on age, weight, or length, are provided for constructing centile charts and calculating standard deviation scores.     

Osmotic lysis of tumor spill in ovarian cancer: A murine model

OBJECTIVE: Our purpose was to determine, in the murine model, whether human ovarian cancer cells injected intraperitoneally are subject to osmotic lysis by peritoneal lavage with sterile water, thereby decreasing the establishment of peritoneal implants. STUDY DESIGN: Preliminary experiments on six nude mice determined that the injection of 20 million cells of the SKOV-3 cell line reliably leads to the establishment of intraperitoneal tumor xenografts in the mice within 60 days. Four other nude mice functioned as sham controls undergoing peritoneal lavage with 3 to 4 ml of saline solution or sterile water to determine any adverse effects from the lavage alone. Subsequently, 36 nude (nu/nu) mice were injected intraperitoneally with 1 ml of the SKOV-3 cell line at a concentration of 20 million cells per milliliter. Alternate mice then underwent intraperitoneal lavage with either 3 to 4 ml of normal saline solution (control group) or sterile water (study group). The mice were followed up until tumor growth caused a moribund status or until 60 days after injection and then were killed. At necropsy the number and size of tumor nodules were recorded, and each mouse was assigned a composite tumor score. Statistical comparison used the χ² or Fisher's exact test for discrete variables. Time to failure analysis used the Kaplan-Meier method. RESULTS: Tumor growth occurred in 35 of 36 (97%) of the mice during the study period. In the first 30 days 89% of the saline solution group grew clinically visible tumor compared with 55% of the water group (p = 0.03). Ascites developed more frequently in the water group than in the saline solution group. The median tumor scores at death were significantly higher for the water group versus the saline solution group. Survival time, as determined by the time from injection until moribund status, was worse for the water group (p = 0.002). CONCLUSIONS: Intraperitoneal lavage with sterile water did not offer protection against the establishment of xenografts after the intraperitoneal injection of human ovarian cancer cells in the nude mouse model. (Am J Obstet Gynecol 1996;175:1489-92.)     

Cardiac abnormalities in end stage renal failure and anaemia

Thirteen anaemic children on dialysis were assessed to determine the incidence of cardiac changes in end stage renal failure. Nine children had an increased cardiothoracic ratio on radiography. The electrocardiogram was abnormal in every case but no child had left ventricular hypertrophy as assessed by voltage criteria. However, left ventricular hypertrophy, often gross, was found on echocardiography in 12 children and affected the interventricular septum disproportionately. Cardiac index was increased in 10 patients as a result of an increased left ventricular stroke volume rather than heart rate. Left ventricular hypertrophy was significantly greater in those on treatment for hypertension and in those with the highest cardiac index. Abnormal diastolic ventricular function was found in 6/11 children. Children with end stage renal failure have significant cardiac abnormalities that are likely to contribute to the high cardiovascular mortality in this group. Anaemia and hypertension, or its treatment, probably contribute to these changes. Voltage criteria on electrocardiogram are of no value in detecting left ventricular hypertrophy. Echocardiography must be performed, with the results corrected for age and surface area, in order to detect and follow these abnormalities.     

Second primary neoplasms in a population-based series of patients diagnosed with renal tumours in childhood

Eight second malignant tumours developed in a population-based series of 218 patients diagnosed with renal tumours in childhood: renal cell carcinoma of the contralateral kidney, hepatocellular carcinoma, Hodgkin's disease, and 4 basal cell and 1 squamous cell carcinomas of skin. Excess risk of developing a second malignancy (excluding skin carcinomas but including a registrable spinal neurofibroma) was 14.7 (95% Cl 4.0-37.7, P = 0.0003) for Wilms' tumour patients. Cumulative incidence of second malignant neoplasms (excluding skin carcinoma) was zero at 10 years, 5.0% at 20 years, and 10.2% at 30 years. The most common second neoplasms seen were benign osseous/chondromatous tumours and 4 of the 7 Wilms' tumour patients with malignant tumours had previous or synchronous tumours of this kind. Development of bony exostoses may be a marker for those patients at particularly high risk of subsequent malignancy. © 1994 wiley-Liss, Inc.     

Nalmefene to prevent epidural narcotic side effects in pediatric patients: a pharmacokinetic and safety study

STUDY OBJECTIVE: To determine the pharmacokinetics and preliminary efficacy of nalmefene in children in preventing epidural-induced narcotic side effects. DESIGN: Double-blind, placebo-controlled study. SETTING: University-affiliated children's hospital. PATIENTS: Thirty-four children (aged 2-12 yrs) undergoing cardiothoracic surgery with epidural anesthesia. INTERVENTIONS: Patients were randomized to receive intravenous bolus nalmefene 1 microg/kg or placebo. MEASUREMENTS AND MAIN RESULTS: Six blood samples (one before nalmefene administration and five from 13 randomly designated time points) from each patient were assayed to determine plasma nalmefene concentrations. Patients were assessed for pain, nausea, vomiting, and urinary retention for 24 hours after administration. Concentration-time data were analyzed by a limited sampling strategy with adult pharmacokinetic parameters used as Bayesian priors. A two-compartment, first-order model was fitted to the data using ADAPT II. Pharmacokinetic parameter estimates in these patients were similar to values reported in adults. The initial disposition half-life (t(1/2alpha)) was 0.36+/-0.11 hour, the terminal elimination half-life (t(1/2beta)) 8.7+/-2.3 hours, clearance 0.729+/-0.172 L/kg/hr, and steady-state volume of distribution 7.21+/-2.49 L/kg. Ability to prevent epidural narcotic-induced side effects could not be documented at the 1-microg/kg dose. No statistically significant differences were noted between study and placebo groups with regard to pain, nausea, vomiting, or urinary retention. CONCLUSION: Nalmefene has similar pharmacokinetics in children as in adults. It was administered safely to these patients and did not produce unmanageable pain.