Cranial computed tomography findings in children with acute lymphoblastic leukemia at diagnosis

Forty children newly diagnosed with acute lymphoblastic leukemia (ALL) were examined by computed tomography (CT) of the central nervous system (CNS) on hospital admission before any medication was started. The results of the CT scans were defined as normal, borderline (slight or moderate dilatation of the ventricular system and/or basal cisterns and/or convolutional sulci), or pathologic (severe cerebral atrophy). The mean age of the patients was 5.8 years (range 1.7-15 years). Sixteen of the 40 patients (40%) had CT scan abnormalities with 14 patients having borderline scans and two patients pathologic scans. No child presented with neurologic symptoms or CNS leukemia. These data suggest that CT abnormalities of the brain are common in children with ALL at diagnosis and may represent clinically unsuspected lesions secondary to leukemia.     

Plasma long-chain polyunsaturated fatty acids and neurodevelopment through the first 12 months of life in phenylketonuria

The aims of the study were to examine the relationship between long-chain polyunsaturated fatty acid (LCPUFA) status at diagnosis of phenylketonuria (PKU) and neurodevelopment through the first 12 months of life, and to assess whether any difference exists between infants breastfed and bottlefed in the first days of life on the basis of LCPUFA status. Twenty infants with PKU were prospectively examined through the first year of life. Plasma fatty acids were measured in infants at diagnosis. Plasma phenylalanine levels were determined monthly. Main outcome measures were the Bayley Mental Developmental Index (MDI) and Psychomotor Developmental Index (PDI) at 5 and 12 months of age, and the visual function at 12 months, evaluated by P100 wave latencies with visual evoked potentials. A higher PDI score was associated with higher plasma arachidonic acid at diagnosis (adjusted correlation coefficient of PDI at 5 months, r=0.38, p=0.05). P100 wave latency at 15 minutes of arc (15') was associated with the early plasma arachidonic acid (adjusted r=-0.56, p=0.02) and phenylalanine levels at 12 months (adjusted r=0.22, p=0.05). No association was found between MDI score and any essential fatty acids. Breastfed infants exhibited higher plasma arachidonic acid (mean difference, delta, =3.4%; 95% confidence interval [CI]=1.2-5.6%) and shorter P100 wave latency at 15' (delta=-21 ms, 95%CI=-30 to -12) than bottlefed infants. Within the population of this study, a weak positive association has been found between plasma LCPUFAs at diagnosis (higher in breastfed infants) and neurodevelopmental indices through the first year of life.     

Effects of long-chain polyunsaturated fatty acid supplementation on fatty acid status and visual function in treated children with hyperphenylalaninemia

BACKGROUND: Children with phenylalanine-hydroxylase deficiency (type-I hyperphenylalaninemia, HPA) follow a low-phenylalanine diet, severely restricted in animal foods and long-chain polyunsaturated fatty acids (LCPUFA). Consequently, they have a poor LCPUFA status, particularly for docosahexaenoic acid (DHA). DHA is relevant to visual and neural development. OBJECTIVE: To investigate the effects of a 12-month supplementation with LCPUFA in a double-blind, placebo-controlled trial in treated children with HPA. STUDY DESIGN: Twenty children with well-controlled HPA were randomly allocated to receive either a fat supplement (supplying 26% as fatty acids including DHA, 8%) or a placebo. The fatty acid composition of erythrocyte lipids and the visual evoked potentials were measured at baseline and after 12 months of supplementation. Reference data were obtained from healthy children of comparable age. RESULTS: At baseline children with HPA had a poorer DHA status and prolonged P100 wave latencies than the reference group. At the end of the trial the LCPUFA group showed a significant increase in DHA levels of erythrocyte lipids. In the LCPUFA group P100 wave latency decreased and was negatively associated with the DHA changes. CONCLUSIONS: A balanced dietary supplementation with LCPUFA in children with HPA is associated with an increase of the DHA pool and improved visual function.     

Decay rate of inspiratory muscle pressure during expiration in man.

Decay rate of inspiratory muscle pressure (PmusI) was studied in 4 subjects during post-inspiratory period of zero flow (TEz) occurring under discontinuous inspiratory elastic load (DIL). End-inspiratory pressure (PmuseI) was increased by dead spaces or exercises. Decay rate was related to PmuseI by a power function with exponent greater than 1. It was not directly affected by concomitant changes of PCO2. It did not increase when an expiratory resistive load was added, i.e. when braking action of inspiratory muscles was no longer required. Time course of PmusI during TEz was more straight than exponential. Relative decay rate increased with PmuseI and with decrease of inspiratory or expiratory time. Experiments with resistive loads suggest that relative rate is mainly related to timing factors. During voluntary inspiratory efforts with closed airways, relative decay rate was not related to PmuseI, while decay rate increased linearly with PmuseI.