13C尿素呼吸试验快速诊断儿童Hp现症感染

探讨13C尿素呼吸试验快速诊断儿童Hp现在感染的方法。方法采用13C尿素呼吸试验（C13UreaBreathTest,C13UBT）。结果340例反复脐周、上腹部痛的患儿有99例检出Hp现症感染,检出率29．1％;本研究发现,2～、5～、10～14a三组患儿Hp检出率分别为28．6％（20／70）,29．1％（66／227）,30．2％（13／43）,经统计学处理P＞0．05。结论小儿反复慢性腹痛与Hp现症感染密切相关;Hp现症感染与年龄无关;13C尿素呼吸试验诊断Hp现症感染方法简单,无创安全,快速且准确性高,为诊断Hp现症感染的有效手段。     

~(13)C呼吸试验对儿童幽门螺杆菌感染的诊断价值

目的　应用胃镜检查及血清抗幽门螺杆菌抗体 (HP IgG)的检测结果对比13 C尿素呼吸试验 (13 C UBT) ,评价13 C UBT对儿童幽门螺杆菌 (HP)感染的诊断可靠性。方法　 1997年 10月～ 1999年 12月我院消化门诊具有反复中上腹痛、脐周痛等上消化道症状的患儿 5 89例 ,年龄 4～ 14岁、平均9岁 ;其中 435例进行13 C UBT检查 ,检测当日早晨空腹口服一杯麦片饮食延缓胃排空 ,接着口服 5 0mg13 C 尿素试剂 ,于服药前及服药后半小时取气样 ,应用同位素比值质谱仪检测 ,以DOB表示。检查前停服抗生素 2周者 2 47例 ,停服 4周者 188例。 41例症状严重的患儿同时做胃镜 ,取胃窦粘膜行嗜银染色检查及快速尿素酶试验 ,两者均阳性者确定为HP感染。对比计算13 C UBT检测结果与胃镜检查的符合率、敏感性、特异性、阳性预测值、阴性预测值。同期有 30 0例患儿行血清HP IgG测定 ,其中146例测定了13 C UBT ,观察与HP IgG的符合率。结果　13 C UBT阳性率 2 7 5 8%,随年龄增长感染率上升 ,7岁以后上升明显 ,儿童期感染率剧增 ,符合发展中国家的类型。检查前停服抗生素 2周与 4周者阳性率分别为 2 7 12 %、2 8 19%。血清抗HP IgG阳性率 5 6 7%。胃镜检查阳性率 39%,阳性染色切片中HP菌数量较少。13 C UBT与胃镜检查的符合率为 90     

Helicobacter pylori colonization in children with peptic ulcer disease III. Diagnostic value of the 13C-urea breath test to detect gastric H. pylori colonization

The efficiency of the ¹³C-Urea Breath Test (¹³C-UBT) for the detection of Helicobacter pylori colonization in gastric mucosa was evaluated. The ¹³C-UBT was performed in five pediatric and six adult subjects who had had upper gastrointestinal endoscopy within 2 weeks. H. pylori colonization was confirmed in two pediatric and three adult subjects with peptic ulcer combined with antral gastritis, by histological examination of antral biopsy specimens. When an individual with H. pylori colonization ingested a solution containing ¹³C-urea, a significant amount of ¹³CO₂ appeared in the respiratory CO₂ within 10 min. The mean cumulative percentage dose of ¹³C recovered in the breath over 30 min in the cases with H. pylori colonization was significantly higher than that in those who were not colonized (4.91 vs 0.41, P <0.001). In addition, the effect of antibiotic on the eradication of H. pylori from gastric mucosa was monitored by ¹³C-UBT in two cases. The values of cumulative percentage dose of ¹³C over 30 min fell to the same levels as those observed in H. pylori negative subjects after just 2 weeks treatment with amoxicillin; however, positive results were obtained again 1 month after the withdrawal of amoxicillin. In summary, ¹³C-UBT is a simple, reliable, non-invasive method in the diagnosis of gastric H. pylori colonization especially for pediatric patients.     

Evaluation of a urine antibody test for Helicobacter pylori in Japanese children

OBJECTIVE: To evaluate the accuracy of a urine-based enzyme-linked immunosorbent assay (ELISA) kit for anti-Helicobacter pylori immunoglobulin G antibody (urine-HpELISA) in children, we compared its sensitivity and specificity in reference to (13)C-urea-breath test (UBT) and H pylori stool antigen test (HpSA). STUDY DESIGN: Japanese children without significant upper abdominal symptoms were included (n=100; mean age, 7.0 years; range, 2 to 15). UBT, HpSA, and urine-HpELISA were performed. RESULTS: Of 100 children, 36 and 64 were judged H pylori-positive and H pylori-negative, respectively, by UBT and HpSA. Thirty-four of 36 positive children were positive by urine-HpELISA, and 62 out of 64 negative children were negative by urine-HpELISA. Thus, the urine-HpELISA had 94.4% sensitivity and 96.9% specificity, with accuracy of 96.0%. CONCLUSIONS: The urine-HpELISA is a rapid, inexpensive, reliable, and easy-to-perform method for the diagnosis of H pylori infection in children. It may be useful not only for diagnosis but also for mass screening for epidemiological studies in pediatric population.     

Investigation of <Emphasis Type="Italic">FGF10</Emphasis> as a candidate gene in patients with anorectal malformations and exstrophy of the cloaca

The spectrum of anorectal malformations (ARM) comprises anal stenosis, ectopic anus, recto-urogenital fistula, persistent cloaca, multisystem VACTERL (VATER associations including cardiac and limb anomalies) associations, and exstrophy of the cloaca (CE). The latter also constitutes the most severe form of the bladder exstrophy epispadias complex. Since recent data revealed that fibroblast growth factor 10 (fgf-10) invalidation in mice resulted in a genetically reproducible urorectal defect, we considered FGF10 a suitable candidate gene for ARM and CE, as the protein seems to be involved in the development of this primary developmental field. A total of 20 patients (ten with ARM and VACTERL association, respectively, and ten with CE) were analysed for genomic mutations in the coding regions and exon-intron boundaries of FGF10. Aside from a common FGF10 variant no deviation from the wild-type sequence could be detected and data obtained is not supportive of FGF10 as a genetic cause of ARMs or CE in the patients investigated. Nonetheless, mutations in possibly further upstream located promoter regions and/or unknown regulatory sequences or non-coding regions cannot be excluded. Furthermore, it cannot be ruled out that other genes involved in the signalling pathway of FGF10 may contribute to the formation of these congenital malformations.     

Clinical implications of a slight increase in the gene dosage of <Emphasis Type="Italic">MYCN</Emphasis> in neuroblastoma determined using quantitative PCR

Introduction  Recently, determining the MYCN status in neuroblastoma (NB) using the quantitative PCR (Q-PCR) and FISH instead of the Southern blotting (SB) has been recommended. In order to assess the implications of the gene dosage of MYCN in NB, the MYCN status was evaluated using Q-PCR on DNA extracted from small areas of NB specimens obtained using laser capture microdissection (LCM). Materials and methods   MYCN gene dosages (MYCN/NAGK) were determined in 63 primary NB block samples, as well as in 243 microdissected tissues from 63 samples using Q-PCR. In 23 of 63 cases, the MYCN gene status was evaluated using FISH. Results  Nine block samples with the amplification of MYCN based on SB showed a remarkable increase of the MYCN gene dosage using Q-PCR. Twelve of 54 block samples with no amplification of MYCN based on SB showed a slight increase of the MYCN gene dosage (3.56 ≧ MYCN/NAGK > 1.84), and 8 of these 12 cases were in the advanced stage. Among these 12 cases, 1 case had several LCM areas with a high copy number of MYCN and several LCM areas which showed no increase of MYCN gene. Another case showed a slight increase in the MYCN gene dosage (3.65 ≦ MYCN/NAGK ≦ 4.82) in all LCM areas. In addition, a large number of cells with the MYCN gain were found using FISH in the block sample. In 2 other cases of 12 cases, although no LCM areas showed an increased gene dosage of MYCN, a small number of cells with MYCN amplification were found using FISH were found in the block sample. Conclusion  A slight increase in the gene dosage of MYCN detected by Q-PCR may indicate that the NB tissue contains a small number of cells with the MYCN amplification or a large number of cells with the MYCN gain, which are associated with the aggressive progression of NB.     

Three siblings with triple A syndrome with a novel frameshift mutation in the <Emphasis Type="Italic">AAAS</Emphasis> gene and a review of 17 independent patients with the frequent p.Ser263Pro mutation

The triple A syndrome is an autosomal recessive disorder characterized by adrenal insufficiency, alacrima, achalasia, and impairment of the central, peripheral, and autonomic nervous system functions. The disease is caused by mutations in the AAAS gene on chromosome 12q13 encoding the nuclear pore protein ALADIN. In the present study, we report three siblings with triple A syndrome caused by a compound heterozygous mutation consisting of a novel Val421 frameshift mutation in exon 14 and a previously described Ser236Pro (T>C transition) missense mutation in exon 8. The second mutation is one of the most frequent mutations in the AAAS gene, occurring in 17 independent patients from different countries. With haplotype analysis, we demonstrate a founder effect for at least 13 of the 17 patients. We conclude that, although very helpful in establishing the final diagnosis of triple A syndrome, DNA analysis is not useful for the prediction of the clinical expression and outcome of the disorder. Further investigations are necessary to evaluate the correlation between genotype and clinical phenotype in the triple A syndrome.