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Biomedical subjects

C K Lin

Publications and source records attributed to C K Lin.

At least 37 records · Page 2Linked to original sources
PubMed2001

Enhanced biodegradation of petrochemical wastewater using ozonation and BAC advanced treatment system.

The characteristics of degradation/conversion of bio-refractory and the growth of a biofilm are investigated in laboratory-scale pre-ozonation and lifted moving-bed biological activated carbon (BAC) advanced treatment processes treating phenol, benzoic acid, aminobenzoic acid and petrochemical industry wastewater which contains acrylonitrile butadiene styrene (ABS). The optimal reaction time and ozone dosage of pre-ozonation for bio-refractory conversion were determined to be 30 min and 100-200 mg O3/hr, respectively. After pre-ozonation of 30 min treatment, BOD5/COD ratio of influent and effluent increased apparently from 20 to 35%, approximately. However, the change of pH in pre-ozonation was inconspicuous. The optimal flow rate of influent and air were controlled at 1.6 l/h and 120-150 nl/min in lifted moving-bed BAC advanced treatment reactor. A COD removal efficiency of 85-95% and 70-90% may be maintained by using an organic loading of 3.2-6.3 kg COD/m3 day and 0.6-1.6 kg-COD/m3 day with an HRT of 6.0 h as secondary and advanced treatment system, respectively. The time required for the BAC bed is be regenerated by a thermal regeneration is prolonged 4-5 times more than that of GAC system. It can be estimated that the enhanced COD removal capability of the biofilm was not only due to the increase in the COD removal capability of acclimated bacteria, but also due to species succession of bacteria in bio-film ecosystem.

Adsorption↗
PubMed2001

Factors associated with errors in death certificate completion. A national study in Taiwan.

To identify characteristics of certifying physicians and the deceased that are associated with errors in death certificate completion in Taiwan, we retrospectively reviewed 4123 systematically sampled death certificates issued in 1994. Multivariate analyses were used to assess the associations of various characteristics of the certifying physicians and the deceased with four types of error. Of the 4123 death certificates reviewed, 2525 (61%) were completed correctly. In 289 (7%), only the mechanism(s) of death was given (Major Error 1); in 146 (4%), multiple causal sequences were given in part I (Major Error 2); in 800 (19%), a single causal sequence was given but was not specific enough (Minor Error 1); and in 363 (9%), a single causal sequence was given but the order was incorrect (Minor Error 2). Multiple logistic regression analyses revealed that the probability of error in death certification increased as the age of the deceased increased, the age of the certifier decreased, and the level of the hospital decreased. These findings suggest that training in death certificate completion should focus on younger certifiers and those working at lower level teaching hospitals and nonteaching hospitals. Given the high rate of Minor Error 1, physicians should be reminded to state information as specifically as possible to render cause-of-death statistics more informative.

Adult↗
PubMed2001

Diversity in death certification: a case vignette approach.

Previous studies have revealed high rates of errors in death certification, but few have discussed the nature of these errors. To explore the diversity among physicians in death certification and its relationship with the complexity of the causal sequence of death, we asked 145 physicians attending a continuing medical education course to complete the cause-of-death section on dummy death certificates of four case vignettes. The difficulty in determining the causal sequence of death varied from relatively simple to complex. Variations in death certification were classified according to wording, diagnostic semantics, combinations of expressions, correctness of certification format, and concordance with the referent underlying cause of death (UCOD). Given the same case history information, physicians showed great variation in wording and diagnostic semantics in death certification. The rates of correct certification format and concordance with referent UCOD varied with the level of complexity of the causal sequence of death. The greatest source of diversity was choosing between an acute condition of a chronic disease and the chronic disease itself, and between competing prominent comorbidities. Experience in death certification was significantly associated with correct certification format but not with concordance with referent UCOD. Knowledge of death certification was not associated with correct certification format or concordance with referent UCOD. Our findings indicate that the traditional concept of UCOD tabulation and using a single standard ICD code in evaluating the quality of death certification oversimplifies a complex situation. Variations in death certification, especially the selection of UCOD, were due to differences in interpreting the information rather than differences in knowledge of death certification.

Acute Disease↗
PubMed2001

Eradication of Helicobacter pylori prevents ulcer development in patients with ulcer-like functional dyspepsia.

BACKGROUND: Although the eradication of Helicobacter pylori infection benefits patients with gastric or duodenal ulcers, the value of eradicating the infection in the patients with functional dyspepsia (FD) remains controversial. AIMS: To determine whether eradicating H. pylori can prevent the subsequent development of ulcers or relieve the symptoms of functional dyspepsia patients. METHODS: In a double-blind, placebo-controlled trial, 161 patients infected with H. pylori who had functional dyspepsia were randomly assigned to 7 days of treatment with a lansoprazole-based triple therapy or placebo and then followed for 1 year. The main outcome measures were the development of peptic ulcers and the resolution of symptoms. RESULTS: H. pylori was eradicated in 63 out of 81 patients (78%) in the treatment group and none of the 80 patients (0%) in the placebo group. During the follow-up period, two patients in the treatment group and six patients in the placebo group developed peptic ulcers at repeat endoscopy (2.5% vs. 7.5%; 95% CI: -12 to 2). The reduction in ulcer rates was statistically significant in the 'ulcer-like' sub-group (0% vs. 16.7%; 95% CI: -32 to -2), but not in the 'dysmotility-like' and 'unclassifiable' sub-groups. Regarding symptom response, the resolution rates of symptoms were similar between the treatment and placebo groups (58.0% vs. 55.0%, 95% CI: -12 to 18). Additionally, no significant differences existed in the symptom responses between the treatment and control arms in each of the dyspepsia sub-groups. CONCLUSIONS: Eradicating H. pylori can prevent the subsequent development of peptic ulcers in the patients with 'ulcer-like' functional dyspepsia. However, this approach does not significantly reduce the symptoms of functional dyspepsia patients.

2-Pyridinylmethylsulfinylbenzimidazoles↗
PubMed2001

Comparison of clinical, serological and histological findings between non-ulcer dyspepsia patients with and without Helicobacter pylori infection.

BACKGROUND AND AIMS: The role of Helicobacter pylori (H. pylori) infection in non-ulcer dyspepsia (NUD) remains controversial. This study investigates the clinical, serological and histological differences between patients with H. pylori-positive and -negative NUD. METHODS: One hundred and eighty consecutive patients with NUD were enrolled from January to December 1998. The severity of symptoms was evaluated by the Tucci's scoring system. The histological changes of gastric mucosa were assessed according to the Updated Sydney System, and a fasting blood sample was obtained to test the serum gastrin and pepsinogen I levels. RESULTS: The H. pylori-positive NUD patients were notably older than H. pylori-negative NUD patients (48.2 +/- 15.9 vs 39.8 +/- 15.7 years, P= 0.001). There were no differences in other clinical factors between the two NUD groups. The serum pepsinogen I levels were considerably higher in H. pylori-positive NUD patients than in H. pylori-negative NUD patients (78.9 +/- 42.2 vs 61.5 +/- 43.3 ng/mL, P<0.01). However, no significant differences in serum gastrin levels were discovered between the two groups. The antrum histological scores for chronic inflammation, acute inflammation, gland atrophy and lymphoid follicles were higher in H. pylori-positive NUD patients than in H. pylori-negative NUD patients (2.09 vs 1.01, P<0.001; 1.22 vs 0.36, P<0.001; 0.76 vs 0.36, P<0.01; 0.33 vs 0.13, P<0.01, respectively). CONCLUSIONS: The present study discovered marked differences in age, serum pepsinogen I levels, histological grades of acute inflammation, chronic inflammation, gland atrophy and lymphoid tissue formation between H. pylori-positive and H. pylori-negative NUD patients. Further investigation of the clinical prognosis of the two groups of patients is necessary.

Adult↗
PubMed2001

Quantitative and genotypic analysis of TT virus infection in Chinese blood donors.

BACKGROUND: The TT virus (TTV) is a member of a newly described family of human viruses related to the C ircoviridae viruses. Its association with specific diseases has not been established, and screening of blood donors has not been implemented. To date, 16 genotypes have been identified. STUDY DESIGN AND METHODS: Sera from 471 healthy blood donors (aged 11-58 years) were randomly selected and tested for TTV by the use of two sets of primers: NG59d/NG61d/NG63d primers and T801/T935 primers. Quantitative competitive PCR (QC-PCR) was developed to measure the TTV DNA concentration among the blood donors. Sequencing of a part of the genome was performed to identify the various genotypes. Several samples showed a mixed genotype infection. RESULTS: TTV was detected in 251 (53.3%) of 471 healthy Hong Kong blood donors by the use of NG59d/NG61d/NG63d primers. The prevalence of the virus increased steadily with age (p = 0.03). TTV DNA was detected in 90 percent (90 of a randomly selected 100) of samples by the use of T801/T935 primers. TTV DNA concentration was also measured by QC-PCR in the blood donors who were positive for TTV DNA in the first round of the heminested PCR. TTV titers ranged from 4.8 x 10(2) copies per mL to 6 x 10(4) copies per mL, with a median value of 1.2 x 10(4) copies per mL. Sequencing and phylogenetic analysis of a 223-bp fragment from open reading frame 1 showed three main genotypes (G1 [60.7%], G2 [24.3%], and G3 [14%]) and a new genotype 17 (G17), with the latter bearing 60-percent nucleotide homology with other genotypes deposited at GenBank. In addition, a new TTV subtype, G2f, was found. CONCLUSION: The prevalence of TTV is high in healthy Chinese blood donors. Three main genotypes (G1, G2, and G3) were detected. In addition, a new TTV genotype, tentatively designated as G17, and a new subtype, G2f, were identified.

Adolescent↗
PubMed2001

The effects of endoscopic variceal ligation and propranolol on portal hypertensive gastropathy: a prospective, controlled trial.

BACKGROUND: Endoscopic treatment of esophageal varices may accentuate portal hypertensive gastropathy. The impact of the combination of band ligation and propranolol on this condition remains unknown. METHODS: Patients with history of variceal bleeding were randomized to receive band ligation alone (control group, 40 patients) or a combination of band ligation and propranolol (propranolol group, 37 patients). Serial endoscopic evaluation of gastropathy was performed. Gastropathy was classified into 3 grades and scored as 0, 1, or 2. RESULTS: Before endoscopic treatment, 17% of the control group and 22% of the propranolol group had gastropathy (p = 0.78). The occurrence of gastropathy after endoscopic treatment was significantly higher in the control group than in the propranolol group (p = 0.002). Serial endoscopic follow-up revealed that the mean gastropathy score was significantly higher in the control group than in the propranolol group (p < 0.05). In patients with gastropathy the gastropathy score reached a peak at 6 months after endoscopic treatment in both the control and propranolol groups (85% vs. 48%, respectively). After variceal obliteration, accentuation of gastropathy was significant in the control group (p < 0.01) but not in the propranolol group. Gastropathy was less likely to develop in patients who developed gastric varices. Esophageal variceal recurrence was not related to the development of gastropathy after variceal obliteration with banding. Only one patient in the control group bled from gastropathy. CONCLUSION: Band ligation of esophageal varices may accentuate gastropathy, which in this study was partly relieved by propranolol.

Adult↗
PubMed2001

Effects of turn residues in directing the formation of the beta-sheet and in the stability of the beta-sheet.

The designed peptide (denoted 20-mer, sequence VFITS(D)PGKTYTEV(D)PGOKILQ) has been shown to form a three-strand antiparallel beta-sheet. It is generally believed that the (D)Pro-Gly segment has the propensity to adopt a type II' beta-turn, thereby promoting the formation of this beta-sheet. Here, we replaced (D)Pro-Gly with Asp-Gly, which should favor a type I' turn, to examine the influence of different type of turns on the stability of the beta-sheet. Contrary to our expectation, the mutant peptide, denoted P6D, forms a five-residue type I turn plus a beta-bulge between the first two strands due to a one amino-acid frameshift in the hydrogen bonding network and side-chain inversion of the first beta-strand. In contrast, the same kind of substitution at (D)Pro-14 in the double mutant, denoted P6DP14D, does not yield the same effect. These observations suggest that the SDGK sequence disfavors the type I' conformation while the VDGO sequence favors a type I' turn, and that the frameshift in the first strand provides a way for the peptide to accommodate a disfavored turn sequence by protruding a bulge in the formation of the beta-hairpin. Thus, different types of turns can affect the stability of a beta-structure.

Amino Acid Sequence↗
PubMed2001

Effect of somatostatin on the sphincter of Oddi in patients with acute non-biliary pancreatitis.

BACKGROUND: Somatostatin has been used to prevent pancreatitis after endoscopic retrograde cholangiopancreatography but its effect on acute non-biliary pancreatitis is still unclear. AIM: The purpose of this study was to evaluate the function of the sphincter of Oddi (SO) and the effect of somatostatin on patients with non-biliary pancreatitis. METHODS: Twenty patients (18 males, two females) with acute pancreatitis (alcoholic 18, idiopathic two) received SO manometry within one week after admission. After baseline measurement, a bolus dose of somatostatin (Stilamin, Serono) 250 microg was infused slowly, and SO manometry was repeated after five minutes. Continuous infusion of somatostatin 250 microg/h was given for 12 hours after SO manometry. Serum amylase, lipase, glucose, and C reactive protein (CRP) levels were examined before and after somatostatin infusion. RESULTS: SO manometry was unsuccessful in six patients due to contracted sphincter. In the remaining 14 patients, high SO basal pressure (SOBP >40 mm Hg) was found in seven patients. After somatostatin infusion, mean SOBP decreased from 48.8 (29) to 31.9 (22) mm Hg (p<0.01). One patient had a paradoxical reaction to somatostatin (SOBP increased from 30 to 50 mm Hg) while the other 13 patients had a fall in SOBP after somatostatin. One patient developed abdominal pain with a serum amylase level of 2516 IU/l after SO manometry. No other side effects or changes in amylase, lipase, glucose, or CRP levels were observed in the other 19 patients after SO manometry and somatostatin infusion. DISCUSSION: Sphincter of Oddi dysfunction is common in patients with acute non-biliary pancreatitis and in most cases somatostatin can relax the sphincter.

Acute Disease↗
PubMed2001

alpha-1 antitrypsin phenotypes by isoelectric focusing in a metropolitan southern Chinese population.

AIMS/BACKGROUND: alpha-1 antitrypsin (alpha1AT) is an abundant protease inhibitor in human plasma. Its phenotypic variability has been reported to be associated with pulmonary emphysema and chronic liver diseases. However, alpha1AT deficiency is an uncommon condition in the Chinese population. The aim of this study was to describe the phenotypic distribution of alpha1AT in a southern Chinese population. METHODS: A total of 1085 healthy blood donors underwent alpha1AT phenotyping by isoelectric focusing. RESULTS: Two thirds (66.1%) were homozygous for either M1 or M2, whereas 32.6% were heterozygous for two different M phenotypes. The frequency of allelic variants was only 0.007, and deficiency variants were absent. Compared with earlier studies on southern Chinese populations, this study found a lower frequency of M2, and a higher number of allelic variants, including E, L, N, P, and S. This phenomenon can be attributed to population migration and mixing. CONCLUSIONS: An understanding of the alpha1AT pattern is important for evaluating the predisposition of the population to selected clinical diseases.

Adolescent↗
PubMed2001

Attitudes about organ and tissue donation among the general public and blood donors in Hong Kong.

CONTEXT: The cadaveric organ and tissue donation rate in Hong Kong is not satisfactory; 1 million blood donors are registered and more than 300,000 are active. However, the current attitudes toward organ and tissue donation in the general public and blood donors of Hong Kong are unknown. METHODS: Random general public (n = 1018) and blood donors (n = 1227) of Chinese origin, with age ranging from 16 to 60 years, were interviewed using a standard verified questionnaire that examines attitudes and knowledge of organ and tissue donation. RESULTS: The mean age of the general public and blood donors were 32.6 and 28.9 years, respectively. Of the general public, 44.4% were men and among blood donors, 60% were men. About 56% of both groups thought that organ donation is an obligation of citizens. Blood donors were more aware than the general public about the types of organs that can be donated. When compared with the general public, a significantly higher percentage of blood donors were willing to donate their organs (81% vs 53%), had heard about organ donation cards (98.3% vs 89.5%), and had signed the cards (49.9% vs 22.6%). About 70% of both groups who had signed a card were carrying it. Thirty-nine percent of the general public and 17% of blood donors had not decided whether they would donate. For blood donors, 49.7% were willing to donate their relatives' organs, compared with 41.8% of the general public. Most individuals in both groups would not object to their relatives' decision to donate. About two thirds of individuals in both groups disagreed with the concept of an opt-out law, though only 20% of the general public and 14.4% of blood donors would refuse donation if an opt-out law were in practice. CONCLUSIONS: This study shows that blood donors have better knowledge of organ donation and are more willing to donate their organs and sign an organ donation card than the general public. However, a substantial proportion of blood donors have not signed a donor card. It would be useful to design promotion programs to facilitate blood donors' participation in organ donation.

Adolescent↗
PubMed2001

Cathepsin E and subtypes of intestinal metaplasia in carcinogenesis of the human stomach.

BACKGROUND: Cathepsin E is found mainly over the gastric surface and foveolar epithelial cells, and it also is found in the metaplastic pyloric glands and cancer cells. The exact function of cathepsin E in gastric mucosa remains unclear. The colonic type (type III) of intestinal metaplasia (IM) is strongly associated with intestinal-type gastric carcinoma. IM is considered to be a precancerous lesion. The aim of this study was to find out the role of cathepsin E in IM, dysplasia and cancer of stomach. METHODS: Sixty nine biopsy specimens with IM and dysplasia and 33 gastrectomy specimens with gastric carcinoma were fixed, sectioned and stained with PAS-alcian blue stain, high iron-diamine alcian blue stain to classify IM and immunohistochemical stain to localize cathepsin E. Those patients with dysplastic gastric lesions received regular endoscopic follow-up. RESULTS: Fifteen of 69 patients with gastric dysplasia developed cancer in a median 10.5 months follow-up. Severe dysplasia developed carcinoma significantly higher than mild dysplasia (12/20 vs. 1/25, p < 0.001), and type III intestinal metaplasia seemed to have significantly predilection for severe dysplasia and gastric cancer. Cathepsin E was stained in intestinal metaplasia with dysplastic change in 44/69 specimens (63.8%), and carcinoma in 28/48 (58.3%) specimens, there was no significant difference between intestinal type and diffuse type carcinoma in cathepsin E staining. The positive staining for cathepsin E decreased significantly in severe dysplastic gastric mucosa. CONCLUSIONS: Type III IM is commonly associated with severe dysplasia and cancer; it may be a precancerous lesion. The positive staining of cathepsin E decreased with the severity of gastric dysplasia, representing dedifferentiation of the cells.

Aged↗
PubMed2001

Follow-up of Helicobacter pylori status by using 13C-urea breath test in nonulcer dyspeptic patients after eradication therapy.

BACKGROUND: The role of eradication therapy is still controversial in H. pylori-related nonulcer dyspepsia (NUD). The aim of this study was to follow up the H. pylori status after eradication therapy in patients with NUD by using l3C-urea breath test (UBT). METHODS: Patients with a clinical and endoscopic diagnosis of NUD were included. H. pylori infection was established by endoscopic biopsies and 13C-UBT. Patients with H. pylori infection then received a quadruple therapy with colloidal bismuth subcitrate, metronidazole, tetracycline and lansoprazole. Two months after completion of therapy, endoscopic biopsies and 13C-UBT were performed again to confirm eradication. A follow-up 13C-UBT was carried out again in one year to detect recurrence of H. pylori infection. RESULTS: Eighty-eight of the 148 patients (59.5%) were found to have H. pylori infection by both endoscopic biopsies and 13C-UBT. Anti-H. pylori therapy was given for 55 patients and proved successful in 33 of them two months after the end of therapy. However, recurrence was found one year later in three of these 33 cases, making a recurrence rate of 9.1% (3/33). Three of the 22 cases with unsuccessful eradication were found to have H. pylori eradication at one year by follow-up 13C-UBT. One of the 33 H. pylori-positive patients without anti-H. pylori therapy, who had negative 13C-UBT in one year follow-up, was found taking a high dose and long period of antibiotics. CONCLUSIONS: The recurrence rate of H. pylori infection in our study was higher than that in the Western population. Delayed eradication of H. pylori may occur after anti-H. pylori therapy. Spontaneous eradication is rare in patients not receiving anti-H. pylori eradication.

Breath Tests↗
PubMed2001

Superior mesenteric arteriovenous fistula associated with portal obstruction.

Superior mesenteric arteriovenous fistula is rarely encountered. Unrecognized in early stage, it can cause hazardous sequelae of portal hypertension. Herein we report a rare case of portal obstruction associated with an aneurysmal dilatation of the superior mesenteric vein, which was caused by a superior mesenteric arteriovenous fistula. The patient was a 74-year-old woman admitted for continuous hemetemesis, presenting with a palpable abdominal mass. The computed tomogram revealed a 6.5 cm superior mesenteric venous aneurysm and thrombotic portal venous obstruction. On account of impending shock, an emergent portal venous thrombectomy and portocaval shunt was carried out. Superior mesenteric arterial angiography performed 4 months later confirmed the diagnosis. Being without symptoms, the patient was clinically followed and remained in stable condition for 3 and a half years. The clinical presentation of a mesenteric arteriovenous fistula varies, with occasional gastrointestinal tract hemorrhage. When complicated with portal obstruction, the condition can be disastrous. We believe that creation of a porto-systemic shunt with resection of the arterio-venous fistula is the proper treatment. This patient is now under close observation.

Aged↗
PubMed2001

Sequential changes of gastric hyperplastic polyps following endoscopic ligation.

BACKGROUND: Endoscopic ligation has been extensively applied in the management of esophageal and gastric varices with or without bleeding. The varices are automatically eradicated through the use of ligation. However, whether avascular necrosis will occur in a gastrointestinal polyp when the base is ligated remains unclear. The aims of this pilot study were to investigate the sequential changes of gastric hyperplastic polyps following endoscopic detachable snare ligation and to determine the possibility of induction of avascular necrosis in these lesions following ligation. METHODS: Eleven patients with eighteen gastric hyperplastic polyps were treated with endoscopic detachable-snare ligation. The polyps were observed for 5 minutes and biopsies were then conducted. At 14 days after endoscopic ligation, follow-up endoscopies were performed to assess the outcome of the strangulated polyps. RESULTS: After being strangulated by the detachable snares, a majority of the polyps immediately congested (94%), and then developed cyanotic change (89%) approximately 4 minutes later. Pathological examination revealed severe venous congestion in the lamina propria of the strangulated polyps. On follow-up endoscopy 2 weeks later, all the snares had dropped off, and avascular necrosis occurred in sixteen polyps (89%). All of the polyps with avascular necrosis were detected to have developed cyanotic changes in initial endoscopy. No complications occurred during or following the ligation procedure. CONCLUSIONS: Most gastric hyperplastic polyps develop avascular necrosis following ligation by detachable snare. Cyanotic change is an important predictor of the outcomes of the lesions following endoscopic ligation. The application of this ligation technique in treatment of bleeding or non-bleeding gastrointestinal polyps deserves further investigation.

Adolescent↗
PubMed2000

Treatment with cytotoxic immunosuppression agents increases urinary excretion of JCV in patients with autoimmune disease.

Human JC virus is ubiquitous in human populations and is reactivated frequently in immunosuppressed patients. Fifty-one patients with autoimmune disease receiving immunomodulating therapy were evaluated to study the possible relationship between immunosuppression and JCV viruria. Patients were divided into cytotoxic and noncytotoxic treatment groups based on their prescription. The incidence of JCV viruria in the cytotoxic treatment group was significantly higher than that in the noncytotoxic group (67% vs. 28%; P < 0.05). Most patients with JCV viruria were receiving corticosteroid (P = 0.03 for any dose and P < 0.001 for higher-dose treatments) and cytotoxic agents (P = 0.02). Age, disease duration, and medication duration appeared not to be the precipitating factors of JCV viruria in this study. The results of clinical evaluation indicate that cytotoxic immunosuppression may play an important role in JC virus reactivation.

Adolescent↗
PubMed2000

A 15-minute [13C]-urea breath test for the diagnosis of Helicobacter pylori infection in patients with non-ulcer dyspepsia.

BACKGROUND: Non-ulcer dyspepsia (NUD) accounts for the majority of dyspeptic patients and studies on the epidemiology of Helicobacter pylori infection in NUD depend on a non-invasive and rapid diagnostic test. This study was performed to determine the sensitivity and specificity of a 15-min simplified protocol of the [13C]-urea breath test ([13C]-UBT) for the diagnosis of H. pylori infection in patients with NUD. METHODS: One hundred and thirty-six patients with a clinical and endoscopic diagnosis of NUD were included. The [13C]-UBT was modified from the European standard protocol. The baseline breath sample was collected 5 min after the patient took a test meal and the 13CO2 was collected 15 min after the patient drank 100 mg [13C]-urea. The gold standard used for comparison was either a positive culture or positive histology + positive rapid urease test sampled on upper gastrointestinal endoscopy. RESULTS: The prevalence of H. pylori infection in NUD by the gold standard was 59.6%, whereas that calculated by the [13C]-UBT was 60.3%. The sensitivity and specificity of [13C]-UBT was 93.8 and 89.1% compared with the gold standard. The shortened collection time and simplification of the procedure may have led to a decline in specificity. CONCLUSION: The 15-min [13C]-UBT is a rapid but less specific protocol for detecting the presence of H. pylori infection in patients with NUD.

Adolescent↗