Role of platelet activating factor and tumor necrosis factor-alpha in neonatal necrotizing enterocolitis

Because previous investigations have suggested that platelet activating factor and tumor necrosis factor-alpha (TNF-alpha) are important mediators of experimental necrotizing enterocolitis in the rat, we measured platelet activating factor, acetylhydrolase (the platelet activating factor breakdown enzyme), and TNF-alpha in the plasma of 12 human neonates with necrotizing enterocolitis and eight age-matched control subjects with similar gestational ages, postnatal ages, and weights. Almost all patients with necrotizing enterocolitis had elevated plasma platelet activating factor values (18.1 +/- 3.6 ng/ml vs. 3.1 +/- 0.9 ng/ml in control subjects, p less than 0.01). Plasma acetylhydrolase activity was lower in patients than in control subjects (10.6 +/- 0.7 nmol/ml/min vs 23.0 +/- 1.4 nmol/ml/min, p less than 0.01). Plasma TNF-alpha concentration was significantly elevated in patients with necrotizing enterocolitis (136 +/- 75 U/ml vs 1.5 +/- 0.8 U/ml, p less than 0.05), although the individual variation was high. There was no correlation between individual TNF-alpha and platelet activating factor levels. We conclude that platelet activating factor and TNF-alpha are elevated in patients with necrotizing enterocolitis and that suppressed platelet activating factor degradation contributes to the increased platelet activating factor levels; platelet activating factor and TNF-alpha may contribute to the pathophysiology of necrotizing enterocolitis.     

Persisting glomerular hyperfiltration in short-term diabetic children without microalbuminuria

The renal function in a group of diabetic children (n=29;age;4-17 yr; IDDM duration: 1,5-13 yr) was studied with a 3 year interval. At the first evaluation glomerular filtration rate (GFR) as assessed by inulin clearance was significantly increased compared to control values (167 +/- 32 vs. 124 +/- 18 ml/min/1.73 m2; pl less than 0.01). Eighteen out of 29 children exhibited a glomerular hyperfiltration (GFR greater than 160). Three years later mean GFR was identical (169 +/- 25 ml/min/1.73 m2) and 16 children were hyperfiltrating. Among them, 11 have had a persisting glomerular hyperfiltration over the 3-year period. Renal plasma flow (RPF) was positively correlated to GFR (r=0.7; p less than 0.01) and remained elevated at both evaluations (794 +/- 163 and 812 +/- 157 ml/min/1.73 m2, p greater than 0.01 vs, control values). When the children were separated into 3 groups according to IDDM duration no significant differences were observed in the results for GFR and RPF, Mean urinary albumin excretion was comparable at the 3-year interval, and not significantly different from the control values (5.2 +/- 3.7 and 8.2 +/- 6.6 respectively vs. 8.65 +/- 4 microgram/min). None of the children demonstrated a persistent microalbuminuria. This study reveals a high proportion of diabetic children with a persisting glomerular hyperfiltration, without any other symptom of incipiens nephropathy, If elevated GFR plays an important role in the development of diabetic nephropathy, this study emphasizes the value of regular evaluation of renal function in diabetic children.     

Five- to 7-year-old children with Helicobacter pylori infection are smaller than Helicobacter-negative children: a cross-sectional population-based study of 3,315 children.

OBJECTIVE: To test whether Helicobacter pylori-positive children are smaller and weigh less than H pylori-negative children. DESIGN: Cross-sectional population-based study. PARTICIPANTS: In 3,315 5-to 7-year-old preschool and school children, the putative influence of H pylori infection on growth was investigated. Standing height and weight were analyzed in relation to H pylori infection. The diagnosis of H pylori infection was established by 13C-urea-breath test. RESULTS: The prevalence of H pylori infection in boys was 7.2% (95% confidence interval, 5.9-8.9; n = 1,550) and in girls was 6.1% (95% confidence interval, 4.9-7.3; n = 1,552) H pylori-positive children were smaller than noninfected children (117.6 +/- 5.5 cm vs. 118.9 +/- 5.7 cm; P < 0.01). Although H pylori-positive boys were 2.06 cm smaller than H pylori-negative boys (117.4 +/- 5.6 cm vs. 119.5 +/- 5.7 cm; P < 0.001), the difference in girls was not significant (117.9 +/- 5.3 cm vs. 118.4 +/- 5.7 cm). When standing height was adjusted for age, the found differences were more pronounced. Differences between the infected and noninfected children with regard to body weight were not significant (22.4 +/- 4.0 kg vs. 22.1 +/- 4.0 kg), nor was there a significant difference with regard to body-mass index. However, boys with H pylori infection had a lower weight than noninfected boys (21.6 +/- 3.3 kg vs. 22.6 +/- 4.0 kg; P < 0.01), but in girls, these differences were not observed (22.2 +/- 4.0 vs. 22.8 +/- 4.6 kg, respectively). When weight was adjusted for age, H pylori -positive children also had a lower weight than H pylori -negative children because of the lower weight of boys. CONCLUSIONS: H pylori infection is associated with growth delay, growth retardation, or both in affected children.     

Abnormal serum phenylalanine-tyrosine ratio and hyperferritinemia in malignant histiocytosis

Nine cases of childhood malignant histiocytosis (MH) showed an abnormally high serum phenylalanine (Phe)/tyrosine (Tyr) ratio (3.47 +/- 1.32) coincident with hyperferritinemia (50,800 +/- 33,600 ng/ml). Lactate dehydrogenase activity was also increased in these patients. These values were compared with data on sera from two groups of patients, acute leukemia cases (n = 14) and measles cases (n = 13), and with control values from normal healthy children (n = 38). The Phe/Tyr ratio was 1.57 +/- 0.54 for the acute leukemia (p less than 0.01) and 2.58 +/- 1.46 for the measles cases (NS), serum ferritin was 245 +/- 124 ng/ml for acute leukemia (p less than 0.01) and 167 +/- 117 ng/ml for measles (p less than 0.01). Accordingly, the concurrence of both abnormalities is considered to be characteristic for MH. It was also found that both serum Phe/Tyr ratio and ferritin levels reflect the disease activity, indicating that these two factors are useful prognostic indicators in the treatment of patients with MH.     

Improved erythrocyte survival with combined vitamin E and selenium therapy in children with glucose-6-phosphate dehydrogenase deficiency and mild chronic hemolysis

To study the antioxidant effect of high-dose vitamin E alone and in combination with selenium in patients with glucose-6-phosphate dehydrogenase deficiency with mild chronic hemolysis, 36 male children with such manifestations were enrolled consecutively into two equal groups. Group 1 received 800 IU vitamin E daily, and group 2 received 800 IU vitamin E in combination with 25 micrograms selenium. Hematologic status before and 2 months after treatment was evaluated. After treatment there was a significant change toward normal in both groups. The mean red cell half-life increased in group 1 from 16.9 to 22.8 days (P less than 0.01), and in group 2 from 15.6 to 24.3 days (P less than 0.01). A comparison of the mean difference of paired values in the two groups revealed a more significant increase in hemoglobin (0.9 +/- 0.1 gm/dl vs 1.2 +/- 0.2 gm/dl, P less than 0.05), hematocrit (2.4% +/- 0.4% vs 3.8% +/- 0.3%, P less than 0.05), and red cell half-life (5.9 +/- 3.0 days vs 9.1 +/- 4.4 days, P less than 0.01), and more significant reduction in reticulocytes (-0.7% +/- 0.2% vs -1.5% +/- 0.4%, P less than 0.01) in group 2. Clinical assessment and follow-up indicated no side effects related to the drugs.     

Calciotropic hormones in osteoporosis caused by anorexia nervosa

The authors evaluated bone mineralization by single photon absorptiometry and mineral homeostasis in 7 patients with anorexia nervosa. The patients with anorexia nervosa showed a reduction of bone mineralization in respect to age-sex matched normal values. Serum levels of calcium, ionized calcium, phosphate, magnesium, alkaline phosphatase, calcitonin and 25-hydroxyvitamin D were normal as well as phosphate and hydroxyproline urinary excretion. Osteocalcin levels were significantly low as compared to normal values (5.0 +/- 3.0 ng/ml vs 14.3 +/- 5.2 ng/ml, p less than 0.01) as well as urinary calcium excretion (0.02 +/- 1.01 vs 0.08 +/- 0.06, p less than 0.05); 1,25-dihydroxyvitamin D values were low only in 4 patients. Parathyroid hormone means levels were increased in respect to normal values (74.1 +/- 12.7 pg/ml vs 38.0 +/- 12.0, p less than 0.02). We confirm that adolescents with anorexia nervosa showed a reduced bone mineral content and alterations of mineral homeostasis that may contribute to the development of bone mineral loss.     

Soluble low affinity Fc receptors for IgE in the serum of allergic and nonallergic children

IgE-binding factors are thought to have regulatory activity in in vitro IgE synthesis. To obtain evidence of the participation of IgE-binding factors in in vivo IgE synthesis, the serum level of low affinity Fc receptors for IgE (sFc epsilon RII) (IgE-BFs) was examined in 41 nonallergic children and in 37 allergic children whose serum IgE levels were significantly higher than those of nonallergic children. The serum level of sFc epsilon RII showed a marked age-dependent variation. It was highest in infants and then decreased gradually with age. The serum level of sFc epsilon RII in allergic children was significantly higher than that of nonallergic children in early childhood (1128.0 +/- 323.8 vs 777.3 +/- 227.0 pg/ml, p less than 0.01 in infants (less than 1 y) and 851.8 +/- 270.0 vs 579.4 +/- 197.1 pg/ml, p less than 0.05 in children aged 1-2 y) but not in older children (3-15 y). Three allergic infants (less than 1 y) with serum sFc epsilon RII levels higher than the mean + 1 SD (1451.8 pg/ml) of all allergic infants (less than 1 y) had serum IgE levels (geometric mean 125.9 IU/ml) significantly higher than the other seven allergic infants (less than 1 y) (geometric mean 5.6 IU/ml, p less than 0.05). A close positive correlation between the serum level of sFc epsilon RII and the absolute number of Fc epsilon RII(+) peripheral blood lymphocytes was observed (Spearman's rank correlation coefficient = 0.79, p less than 0.001 in 27 allergic and Spearman's rank correlation coefficient = 0.72, p less than 0.001 in 19 nonallergic children). In conclusion, serum sFc epsilon RII may be derived mainly from Fc epsilon RII(+) lymphocytes, and may have relationship to the increased production of IgE in early childhood (0-2 y).     

Cerebrospinal fluid immunoglobulins in children.

Cerebrospinal fluid (CSF) immunoglobulins were measured in 62 normal children, in 9 children with purulent meningitis, and in 10 children with presumptive viral meningitis. The mean values in normal children were IgA 0, IgM 0, and IgG 0.84 +/- 1.4 mg/100 ml (+/- SD). The mean levels of all CSF immunoglobulins were raised in acute bacterial meningitis and were significantly greater than the levels found in viral meningitis. CSF IgM was 0.16 +/- 0.5 mg/100 ml in viral meningitis compared with 2.64 +/- 2.06 mg/100 ml in bacterial meningitis (P less than 0.01). However, these values overlapped to a considerable extent and, generally, measurement of CSF immunoglobulins did not enhance diagnostic accuracy in this group of children.     

Cerebrospinal fluid immunoglobulins in children

Cerebrospinal fluid (CSF) immunoglobulins were measured in 62 normal children, in 9 children with purulent meningitis, and in 10 children with presumptive viral meningitis. The mean values in normal children were IgA 0, IgM 0, and IgG 0.84 +/- 1.4 mg/100 ml (+/- SD). The mean levels of all CSF immunoglobulins were raised in acute bacterial meningitis and were significantly greater than the levels found in viral meningitis. CSF IgM was 0.16 +/- 0.5 mg/100 ml in viral meningitis compared with 2.64 +/- 2.06 mg/100 ml in bacterial meningitis (P less than 0.01). However, these values overlapped to a considerable extent and, generally, measurement of CSF immunoglobulins did not enhance diagnostic accuracy in this group of children.     

重组人超氧化物歧化酶对胎粪诱导肺损伤的保护作用及其机制研究

目的探讨胎粪诱导急性肺损伤的发病机制及抗氧化剂重组人超氧化物歧化酶(recombinant human superoxide dismutase, rhSOD)的保护作用.方法 32只雄性SD大鼠,随机取出8只经气管置管注入生理盐水1 ml/kg 作为对照(生理盐水组),24只大鼠由气管置管注入20%胎粪1 ml/kg复制大鼠胎粪肺损伤模型,随机分为胎粪组(8只);胎粪+生理盐水组(8只,气管内注入生理盐水1 ml/kg);胎粪+rhSOD组(8只,气管内注入rhSOD 20 mg/ml/kg).24 h后分别行大鼠支气管肺泡灌洗液(BALF)细胞计数和蛋白含量、肺通透指数(BALF蛋白含量/血浆蛋白含量,pulmonary permibility index, PPI)、乳酸脱氢酶(LDH),肺组织匀浆髓过氧化物酶(MPO)活性和丙二醛(MDA)、一氧化氮(NO)含量及超氧化物歧化酶(SOD)活性检测,并观察光镜下动物肺损伤的程度.结果与生理盐水组比较,胎粪组和胎粪+生理盐水组BALF细胞计数、蛋白含量、PPI、LDH及肺组织MPO活性、MDA、NO含量、肺损伤病理评分均显著增高(P均<0.01),肺匀浆SOD活性略有上升,但差异无意义(P>0.05);胎粪组与胎粪+生理盐水组比较,上述指标差异均无显著意义(P均>0.05);与胎粪+生理盐水组比较,胎粪+rhSOD组大鼠BALF细胞计数、LDH、肺匀浆MPO活性、MDA、NO含量、肺损伤病理评分均显著下降(P<0.01或0.05),SOD活性显著增加(P<0.05),而两组间蛋白含量、PPI差异无显著意义(P均>0.05).结论炎症和脂质过氧化损伤参与胎粪诱导肺损伤的发病机制,早期单剂20 mg/kg rhSOD气管内给药可减轻胎粪诱导的大鼠肺炎症反应和脂质过氧化损伤.     

The effect of hypoxia on neurohypophyseal hormone release in fetal and maternal sheep

The effect of hypoxemia on arginine vasopressin (AVP) and oxytocin (OT) release was investigated in the chronically catheterized fetus and ewe. During 30 min of 10% maternal oxygen delivery, mean (+/- SEM) arterial PO2 decreased from 105 +/- 10.6 to 48 +/- 3.5 mm Hg in the ewe and from 21 +/- 1.3 to 12 +/- 0.8 mm Hg in the fetus (each P less than 0.001). Arterial PCO2 decreased from 35 +/- 4.4 to 29 +/- 1.0 mm Hg in the ewe, whereas fetal PCO2 decreased from 43 +/- 2.3 to 35 +/- 3.5 mm Hg (P less than 0.05). Blood pH increased from 7.44 +/- 0.03 to 7.56 +/- 0.04 in the ewe (P less than 0.01) and from 7.36 +/- 0.004 to 7.40 +/- 0.006 in the fetuses (P less than 0.01). Baseline mean AVP levels were identical in ewes and fetuses (0.7 +/- 0.1 microU/ml). After 30 min of hypoxia, plasma AVP levels remained unchanged in the ewes (0.9 +/- 0.1), but increased dramatically in the fetuses (47 +/- 21 microU/ml) (P less than 0.001). There was a highly significant correlation between the duration of hypoxia and log fetal AVP concentrations (r = 0.85). The log fetal plasma AVP also was inversely correlated to the log fetal PO2 values (r = 0.83). Mean baseline fetal and maternal plasma OT levels were 2.6 +/- 0.5 microU/ml and 2.2 +/- 0.5 microU/ml, respectively. After 30 min of hypoxia fetal and maternal OT values were 2.9 +/- 0.8 microU/ml (not significant).     

Adenosine deaminase in childhood pulmonary tuberculosis: diagnostic value in serum.

The diagnostic value of serum adenosine deaminase (ADA) activity was evaluated in childhood pulmonary tuberculosis. Serum ADA levels were measured in 20 children diagnosed with pulmonary tuberculosis (group 1) and 150 children (group 2) including 128 with tuberculosis infection (Mantoux test positive) and 22 healthy children. In group 1, the mean serum ADA activity was 74.06 +/- 18.5 U/l, which was significantly (p < 0.001) higher than that of group 2 (40.36 +/- 12.0 U/l). A serum ADA level of > or = 53.76 U/l had a sensitivity of 100 per cent, specificity of 90.7 per cent, positive predictive value of 58.8 per cent, and a negative predictive value of 100 per cent in children with tuberculosis disease. To conclude, measurement of serum ADA activity was a useful diagnostic tool in childhood pulmonary tuberculosis.     

托吡酯治疗后癫(癎)患儿体重和血浆甘丙肽的变化

目的探讨癫痫患儿托吡酯治疗后体重变化与血浆甘丙肽的关系。方法对服用托吡酯的61例癫痫患儿用放射免疫法测定治疗前后血浆甘丙肽浓度和观察身高、体重变化,并以16例健康儿童作为对照。结果①服托吡酯后22例（36．1％）体重下降,该组甘丙肽浓度降低有统计学意义（t=2．91,P〈0．01）。体重增加组甘丙肽变化没有统计学意义（t=1．67,P〉0．05）。对照组甘丙肽变化无统计学意义（t=1．72,P〉0．05）。②体重下降组中18例（81．8％）患儿食欲变差,与体重增加组相比,差异有统计学意义（X^2=28．50,P〈0．001）。③食欲差组甘丙肽浓度降低有统计学意义（t=4．84,P〈0．001）,而食欲好组下降无统计学意义（t=1．04,P〉0．05）。④癫痫患儿治疗后体重指数的下降[（17．48±2．22）kg／m^2比（15．24±2．38）kg／m^2]有统计学意义（t=8．628,P〈0．01）。对照组是增加的。结论服用托吡酯后部分癫痫患儿体重会有显著下降和食欲减退,同时伴有血浆中甘丙肽水平显著的下降。提示托吡酯治疗引起的体重降低和食欲减退可能与甘丙肽浓度降低有关。     

Body composition and components of energy expenditure in children with end-stage liver disease

BACKGROUND: Better understanding of body composition and energy metabolism in pediatric liver disease may provide a scientific basis for improved medical therapy aimed at achieving optimal nutrition, slowing progression to end-stage liver disease (ESLD), and improving the outcome of liver transplantation. METHODS: Twenty-one children less than 2 years of age with ESLD awaiting liver transplantation and 15 healthy, aged-matched controls had body compartment analysis using a four compartment model (body cell mass, fat mass, extracellular water, and extracellular solids). Subjects also had measurements of resting energy expenditure (REE) and respiratory quotient (RQ) by indirect calorimetry. Nine patients and 15 control subjects also had measurements of total energy expenditure (TEE) using doubly labelled water. RESULTS: Mean weights and heights were similar in the two groups. Compared with control subjects, children with ESLD had higher relative mean body cell mass (33 +/- 2% vs 29 +/- 1% of body weight, P < 0.05), but had similar fat mass, extracellular water, and extracellular solid compartments (18% vs 20%, 41% vs 38%, and 7% vs 13% of body weight respectively). Compared with control subjects, children with ESLD had 27% higher mean REE/body weight (0.285 +/- 0.013 vs 0.218. +/- 0.013 mJ/kg/24h, P < 0.001), 16% higher REE/unit cell mass (P < 0.05); and lower mean RQ (P < 0.05). Mean TEE of patients was 4.70 +/- 0.49 mJ/24h vs 3.19 +/- 0.76 in controls, (P < 0.01). CONCLUSIONS: In children, ESLD is a hypermetabolic state adversely affecting the relationship between metabolic and nonmetabolic body compartments. There is increased metabolic activity within the body cell mass with excess lipid oxidation during fasting and at rest. These findings have implications for the design of appropriate nutritional therapy.     

Early childhood hyperkalemia: variety of pseudohypoaldosteronism

Fractional excretion of electrolytes, renal acidification capacity and the renin-aldosterone system have been studied in 5 non-azotemic children, 19-25 months old, with mineralocorticoid resistant hyperkalemia, discovered in the first month of life. Although fractional potassium excretion was similar in patients and in a group of control healthy children (13.8 +/- 5.2% vs. 8.7 +/- 6.4%) it was inappropriately low in the patients for their higher potassium concentration. Fractional sodium excretion was significantly increased in the patients (1.6 +/- 0.3% vs. 0.67 +/- 0.4, p less than 0.02). Normal net acid and ammonium excretion and intact ability to lower urinary pH during acid loading were observed in all patients. Mean values for plasma aldosterone (37.0 +/- 9.1 vs. 13.9 +/- 11.2 ng/dl), plasma renin activity (12.5 +/- 3.9 vs. 8 +/- 2.8 ng/ml/h) and plasma aldosterone/plasma potassium ratio (7.11 +/- 1.5 vs. 3.08 +/- 1.7) were higher in the patients than in the control subjects (all p less than 0.001). These data support the hypothesis that a partial lack of response of the renal tubule to endogenous mineralocorticoids was present in the patients. This type of pseudohypoaldosteronism is less severe than that described for the classic form and for early childhood renal acidosis.     

Decreased prolactin secretion in childhood obesity

Twelve obese patients and 7 control subjects, age and sex matched, whose weights were greater than 200% of ideal weight and 100% of ideal body weight, respectively, underwent intravenous insulin and thyroid releasing hormone (TRH) tests. Serial prolactin growth hormone, insulin, blood sugar, cortisol, glucagon, thyrotropin stimulating hormone, thyroxine, and triiodothyronine were obtained by RIA. Obese patients showed no significant differences from controls in basal and nadir glucose, basal and peak glucagon, cortisol, and thyroid responses to both tests. Basal insulin levels were higher (36 +/- 9.4 vs 10 +/- 2.3 microU/ml, P less than 0.05) and peak growth hormone responses after insulin were lower in the obese group (6.1 +/- 1.1 vs 12.7 +/- 3.7 ng/ml, P less than 0.05) than in controls. Whereas all control subjects had prolactin responses to both tests, five of 12 obese patients had no responses to insulin. Obese patients had lower prolactin responses at 30 minutes after insulin (5.4 +/- 0.7 vs 12.9 +/- 3.7 ng/ml, P less than 0.05) and lower prolactin responses at 60 minutes after TRH (9.9 +/- 1.7 vs 20.4 +/- 5.9 ng/ml, P less than 0.05). Maximum prolactin responses after TRH were lower in obese patients (9.9 +/- 2.0 vs 28.8 +/- 10.9 ng/ml, P less than 0.05). Maximum prolactin responses after insulin were lower in obese patients (6.2 +/- 4.1 vs 28.9 +/- 18.3 ng/ml). Thus prolactin secretion in childhood obesity is decreased after both stimuli, but more so after IV insulin that TRH, and suggests that, as in adult hypothalamic obesity, neuroendocrine regulation of prolactin release in obese children is impaired.     

Lack of predictive value of maternal human immunodeficiency virus p24 antigen for transmission of infection to their children.

The association of maternal-to-infant transmission of human immunodeficiency virus type 1 (HIV-1) with maternal p24 antigenemia was assessed in 86 HIV-1-infected mothers. We retrospectively examined serum or plasma samples collected in the peripartum period (delivery +/- 11 days; sd 16.89 days; range, delivery +/- 2 months). Immune complexes of p24 antigen and anti-p24 antibody were dissociated using acid hydrolysis (Method A, glycine-HCl buffer; Method B, HCl) in an attempt to increase the sensitivity of the test. The detection of HIV-1 p24 antigenemia in serum was increased from 23 of 86 (26.7%) to 37 of 82 (45.1%) following acid hydrolysis with Method A (chi square = 5.4, P = 0.02) and to 36 of 78 (46.1%) with Method B (chi square = 5.874, P = 0.015). Mothers of HIV-1-infected children were no more likely to have p24 antigenemia than mothers of seroreverted infants when untreated samples were assayed (7 of 23 vs. 10 of 48; chi square = 0.348, P = 0.55). Although acid hydrolysis increased the ability to detect p24 antigen, it did not enhance any association between p24 antigenemia and maternal-to-infant transmission of HIV infection: Method A, 9 of 23 in mothers of infected children vs. 21 of 45 in mothers of seroreverted children (chi square = 0.112, P = 0.738); and Method B, 9 of 22 in mothers of infected children vs. 18 of 42 in mothers of seroreverted children (chi square = 0.014; P = 0.907), respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Arterial catheter-related infections in children. A 1-year cohort analysis

To determine the incidence of infection secondary to arterial catheterization in children as well as the risk markers, we prospectively evaluated, during a 1-year period, all arterial catheters installed in children admitted to the pediatric intensive care unit. A total of 340 cannulas were placed in 310 children aged 80 +/- 4 months (mean +/- SEM) for a period of 64 +/- 4 hours. Most catheters were inserted percutaneously (99%) in the radial artery (86.5%). Ninety-two percent (313/340) of the catheters were sterile (group 1), 5% (17/340) were contaminated (less than 10 colony-forming units on semiquantitative culture) (group 2), and 3% (10/340) were considered either locally infected (ie, greater than or equal to 10 colony-forming units) (eight of 10) or associated with a possible catheter-related sepsis (two of 10) (group 3, or infected group). The incidence of local inflammation at the insertion site was higher in group 2 than in group 1 (18% vs 2.9%) but not statistically different between groups 3 and 1 (10% vs 2.9%). The duration of arterial catheterization was longer in group 3 than in group 1 (125 +/- 31 vs 61 +/- 4 hours). The risk of infection was nonexistent in the first 48 hours of catheterization. Thereafter it was calculated as being 6.2% (10/161), but it correlated poorly with the duration of arterial catheterization. These results confirm the very low incidence of infection related to arterial catheterization in children. Thus, routine catheter reinsertion is, in our opinion, unjustified.     

肥胖儿童血浆同型半胱氨酸含量及动脉病变的研究

目的　探讨单纯性肥胖儿童是否存在高同型半胱氨酸血症和早期动脉粥样病变。方法　68例 6 ~14岁单纯性肥胖症儿童与 26例正常同龄儿童对照,多普勒二维超声检测颈动脉内膜 中层厚度(IMT)、肱动脉血流介导的内皮依赖性扩张功能并探查肝脏形态结构,化学发光法测定血浆同型半胱氨酸。生化分析法检测全套血脂。结果　肥胖儿童右颈总动脉IMT( 0.54±0.13 )mm,右颈内动脉IMT(0.69±0.14)mm,左颈总动脉IMT(0.52±0.12)mm,左颈内动脉IMT(0.67±0.14)mm;正常儿童右颈总动脉IMT(0.45±0.04)mm,右颈内动脉IMT(0.46±0.04)mm,左颈总动脉IMT(0.45±0.05)mm,左颈内动脉IMT(0.46±0 03)mm,肥胖儿童明显增厚(P<0.01)。肥胖儿童肱动脉血流介导的内皮依赖性扩张功能 (11.0±4.3)%,与对照组 (17.5±4.9)%比较,差异有统计学意义(P<0.01)。肥胖儿童血浆同型半胱氨酸含量(7.9±2.7)μmol/L,与正常儿童血浆同型半胱氨酸含量(5.6±2.1)μmol/L比较差异有统计学意义 (P<0.01)。肥胖儿童总胆固醇 (TC)、甘油三脂(TG)、低密度脂蛋白胆固醇 (LDL-ch)、载脂蛋白B(apoB)明显高于对照组,差异有统计学意义(P<0.01);高密度脂蛋白胆固醇 (HDL ch)、载脂蛋白A(apoA)与对照组比较,差异无统计学意义(P>0.05)。58%肥胖儿童存在脂肪肝或脂肪肝倾     

Assessment of left ventricular function in secundum atrial septal defect: evaluation by determination of volume, pressure, and external systolic time indices.

Left ventricular function and volume data from 17 control subjects and 27 young patients with secundum atrial septal defect (ASD) without overt left or right ventricular failure were compared. ASD patients were subdivided in low shunt (Qp/Qs less than 2.0) and high shunt (Qp/Qs larger than or equal to 2.0) groups. Mean left ventricular (LV) stroke volume was significantly less in ASD patients (46 +/- 16 ml/m2 in the low shunt and 44 +/- 9 ml/m2 in high shunt group) compared with control patients (51 +/- 13 ml/m2, P less than 0.01 and P less than 0.02, respectively). There was no significant difference in mean left ventricular end-diastolic volume (LVEDV) between any group of patients (control subjects 67 +/- 17 ml/m2; low shunt ASD 66 +/- 17 Ml/m2, and high shunt ASD 62 +/- 12 ml/m2). High shunt ASD had a significantly lower cardiac index compared with control patients (5.0 liters/min/m2 vs. 5.9 liters/min/m2, P less than 0.02). Both low shunt and high shunt ASD showed significantly lower stroke work indices than control subjects (42 +/- 13 GmM/m2 and 37 +/- 8 GmM/m2 compared with 51 +/- 14 GmM/M2 , P less than 0.05 and P less than 0.001, respectively) but only the high shunt group had a significantly lower peak systolic pressure (94 +/- 12 mm Hg vs. 109 +/- 11 mm Hg for control patients, P less than 0.01). There was no significant difference between the control and ASD groups in LV end-diastolic, mean right atrial, right ventricular end-diastolic, and pulmonary pressures. External systolic time intervals were compared in 5 control and 12 ASD patients. There was no significant difference between the two groups of patients in absolute values or indices for pre-ejection period, ejection time, or electromechanical systole. However, the ratio of the pre-ejection period index to left ventricular ejection time index (PEPI/LVETI) was significantly higher in ASD patients (P less than 0.05). In young subjects with large shunt ASD, certain indicators of left ventricular function are depressed. Evaluation of PEPI/LVETI may allow noninvasive determination of LV function.