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The lack of epidemiological data on the frequency and/or burden of organic acidurias (OA) and mitochondrial fatty acid transport and oxidation disorders (mtFATOD) is one reason for hesitation to expand newborn screening (NBS) by tandem mass spectrometry (MS-MS). From 1999 to 2000, the frequency of ten potentially treatable OA and mtFATOD was assessed by active nation-wide surveillance on cases presenting with clinical symptoms using the German Paediatric Surveillance Unit (ESPED) system. Case ascertainment was complemented by a second independent source: 3-monthly inquiries in the metabolic laboratories performing secondary selected screening for OA and mtFATOD. Frequency estimates for clinically symptomatic cases older than 7 days in a birth cohort of 844,575 conventionally screened children was compared to the frequency found in a cohort of 382,247 screened by MS-MS in Bavaria and Baden-Württemberg. The overall frequency of the ten conditions considered was 1:8,000 (95% CI 1:11,000–1:6,000) by MS-MS as compared to 1:23,000 (95% CI 1:36,000–1:17,000) in symptomatic cases presenting mainly with metabolic crisis. The contributions of medium-chain acyl-CoA dehydrogenase deficiency (MCADD), other mtFATOD and OA were 29, 4 and 13 among the 46 cases identified by MS-MS, and 19, 1 and 13 among the 33 clinically symptomatic cases, respectively. Acute metabolic crisis, with a lethal outcome in four patients, was reported for 22/33 clinically symptomatic cases. No clinically symptomatic cases were reported from cohorts with screened by MS-MS. Conclusion: ten potentially treatable organic acidurias and mitochondrial fatty acid transport and oxidations disorders were more common than phenylketonuria with organic acidurias accounting for 28% of the cases detected by newborn screening and 39% of the cases identified on high risk screening. These conditions were related to considerable morbidity and mortality. Considerations for their inclusion in expanded newborn screening programmes might be warranted.Abbreviations ESPED Erhebungseinheit für seltene pädiatrische Erkrankungen in Deutschland (German Paediatric Surveillance Unit) - MCADD medium-chain acyl-CoA dehydrogenase deficiency - MS-MS tandem mass spectrometry - mtFATOD mitochondrial fatty acid transport and oxidation disorders - NBS newborn screening - OA organic acidurias  相似文献   
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BACKGROUND: The purpose of the current study was to evaluate whether a totally implanted valved subcutaneous port system would have fewer complications as compared to a standard nonvalved port. METHODS: Study subjects requiring port placement were randomized to receive a valved port (PASV; Boston Scientific, Natick, MA) or a nonvalved port (BardPort; Bard Accesss Systems, Salt Lake City, UT). Each port was placed with standard operative technique. Difficulty with blood return, excess time spent accessing the port, and required interventions were reported over the initial 180 days of port usage. RESULTS: Seventy-three patients were randomized to receive either a valved port (n = 37) or a nonvalved port (n = 36). No major complications were identified from port placement, and there were no differences in rates of infection between the 2 ports. A reported inability to withdraw blood was noted in the valved port group on 21 of 364 (5.8%) port accessions and in the nonvalved port group on 37 of 341 (11%) accessions (P = 0.02). Significantly more total time was spent ensuring adequate blood draw from nonvalved ports as opposed to valved ports (750 minutes vs. 1545 minutes, respectively) (P <0.03). CONCLUSIONS: This study revealed that the PASV valved port is associated with significantly fewer instances of poor blood return and less nursing access time, indicating that a port with a PASV valve may be superior to a nonvalved device.  相似文献   
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Background

Constipation is a common problem in childhood, and various radiologic methods have been advocated for investigation. Colonic transit time (CTT) has been used in adults to investigate colonic motility, but few studies evaluate this method in children. Data on CTT in the normal paediatric population are scarce.

Methods

The colonic transit time was measured in 22 healthy children (median age, 10 years; range, 4 to 15 years) by Abrahamsson’s method. Children took bolus ingestions of radiopaque markers on 6 consecutive days, and on day 7 a single abdominal x-ray was performed. This was evaluated for total and segmental colonic transit time.

Results

The mean total CTT was 40 hours, and the upper limit of normal (95th percentile) was 84 hours. The upper limit of normal for segmental transit time was as follows: 14 hours for the ascending, 33 hours for the transverse, 21 hours for the descending, and 41 hours for the rectosigmoid colon.

Conclusions

CTT provides an objective measure to assess childhood constipation. To date, 6 studies using 5 different methods have been published reporting values for healthy children. Comparing these, Abrahamson’s method has low radiation exposure and is well tolerated. This study contributes additional normal values in children.  相似文献   
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Purpose

The aim of this study was to determine the morbidity and medium-term functional outcome of the Duhamel operation and laparotomy and transanal endorectal coloanal anastomosis (TECA) for Hirschsprung’s disease (HSCR).

Methods

The study populations were 34 consecutive children who underwent the Duhamel operation (or Lester Martin modification) and 37 who had the TECA. Demographic details were obtained by case note review, and functional outcome was determined by a combination of outpatient interview, questionnaire, and telephone enquiry.

Results

There was no difference between the groups with respect to age, gender, and length of aganglionic segment. Seventy percent presented as neonates (Duhamel, 24 of 34; TECA, 26 of 37). A single-stage primary pull-through was performed in 17 of 37 children in the TECA group, and in 1 of 34 from the Duhamel group. There was a single perioperative death in the Duhamel group and an unrelated, late death in the TECA group. Postoperative enterocolitis was seen in 13 of 37 TECA children and in a single child from the Duhamel group. A stricture of the pull-through segment was seen in 7 of 37 children after TECA and required temporary diversion in 2 of 9. Late division of a rectal spur was required in 6 of 33 Duhamel children. Requirement for late myectomy was the same in both groups (Duhamel 3 of 33, TECA 4 of 37). Complications requiring stoma formation occurred in 5 of 37 after TECA and 2 of 33 after the Duhamel operation. Two children from the TECA group and 1 from the Duhamel group remain diverted. One child from each group required a re-pull-through procedure. Two patients were lost to follow-up in the TECA group, leaving 34 children in this group and 33 in the Duhamel group in whom functional outcome could be assessed. Functional outcome was similar in the 2 groups.

Conclusions

TECA and Duhamel procedures have similar medium-term functional outcomes. TECA has a high incidence of postoperative enterocolitis and transient stricture formation but is suitable for single-stage neonatal treatment of HSCR.  相似文献   
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