Zhong-yue Li

Zhejiang University, Hangzhou, Zhejiang Sheng, China

Are you Zhong-yue Li?

Claim your profile

Publications (11)0 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Infection with clarithromycin-resistant Helicobacter pylori (Hp) is often predictive of treatment failure. Susceptibility testing for Hp could guide therapy of Hp infections. However, agar dilution approved by the Clinical and Laboratory Standards Institute (CLSI) to test for antimicrobial susceptibility of Hp is time consuming (results are often not available in a week or more). So a more expeditious method is necessary. The purpose of this study was to evaluate polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) test performed directly on gastric biopsy specimen from children to detect 23S rRNA mutations (A2143G and A2144G) indicating clarithromycin resistance. All biopsy specimens were derived from patients presenting with upper gastrointestinal symptoms, submitted to endoscopy in the Affiliated Children's Hospital, Zhejiang University School of Medicine from September 2006 to February 2007. No patients had undergone eradication therapy. Thirty-nine samples randomly selected from positive specimens by rapid urease test, were homogenized in 500 microl brucella broth with 30% glycerol. The 200 microl homogenized fluid was used to purify genomic DNA with the kit according to the instructions provided by manufacturer, and the rest was used to isolate Hp strains by culturing. All the Hp isolates were tested for clarithromycin susceptibility with the agar dilution and classified as resistant if the minimum inhibitory concentrations (MIC) exceeded 1 microg/ml. Simultaneously, PCR-RFLP analysis was performed in order to identify 23S rRNA mutations (A2143G and A2144G). Finally, the two methods were compared by statistics. The agar dilution was used as a standard to determine the sensitivity and specificity of the PCR-RFLP assay. Of the 39 samples, agar dilution and PCR-RFLP method respectively detected 13 (33.3%) and 14 (35.9%) clarithromycin-resistant gastric specimens. The sensitivity and specificity of PCR-RFLP for the detection of Hp in biopsy specimens were both 92%. The positive and negative predictive value was 85.7% and 96% respectively. No statistically significant difference was found between the two methods (chi2=0.06, P>0.05). The rate of Hp resistance to clarithromycin significantly increased compared with a previous report from the authors' hospital in 2004 (chi2=6.20, P<0.05). Rising clarithromycin resistance rates were observed in children who visited the authors' hospital. PCR-RFLP test is reliable and rapid for detection of clarithromycin resistance directly on gastric biopsy specimen from children and may help choose appropriate antibiotic in Hp eradication therapy.
    Zhonghua er ke za zhi. Chinese journal of pediatrics 11/2009; 47(11):848-51.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Duodenogastric reflux (DGR) is a reverse flow of duodenal juice into stomach through pylorus composed of bile acid, pancreatic secretion, and intestinal secretion. The increased entero-gastric reflux results in mucosal injury that may relate not only to reflux gastritis but also esophagitis, gastric ulcers, carcinoma of stomach and esophagus. However, the exact mechanisms of gastric mucosal damage caused by DGR are still unknown. The objective of the present study is to investigate the pathogenic effect of primary DGR on gastric mucosa in children, and to explore the correlation of DGR with clinical symptoms, Hp infection and intragastric acidity. Totally 81 patients with upper gastrointestinal manifestations were enrolled and they were graded according to the symptom scores and underwent endoscopic, histological examinations and 24-hour intra-gastric bilirubin was monitored with Bilitec 2000. Of the 81 cases, 51 underwent the 24-hour intra-gastric pH monitoring by ambulatory pH recorder simultaneously. The total fraction time of bile reflux was considered as a marker to evaluate the severity of DGR. The total fraction time of bile reflux was compared between the patients with positive and negative results under endoscopy and histologically, respectively. The correlations of the total fraction time of bile reflux with clinical symptom score, Hp infection, intragastric acidity were analyzed respectively. The total fraction time of bile reflux in the patients with hyperemia and yellow stain gastric antral mucosa under endoscopy was significantly higher than that without those changes [17.1% (0.5% approximately 53.2%) vs. 6.5% (0 approximately 58.6%), Z = -1.980, P < 0.05; 19.8% (0.5% approximately 58.6%) vs. 8.8% (0 approximately 38.0%), Z = -2.956, P < 0.01 respectively]. Histologically, the cases with intestinal metaplasia had significantly higher total fraction time of bile reflux than in the cases without intestinal metaplasia [29.0% (1.9% approximately 58.6%) vs. 14.3% (0 approximately 53.7%), Z = -2.026, P < 0.05], but no significant difference was found either between the cases with and without chronic inflammation (P > 0.05) or between the cases with and without active inflammation (P > 0.05). The severity of bile reflux was positively correlated with the score of abdominal distention (r = 0.258, P < 0.05), but no correlation with either the severity of intragastric acid (r = -0.124, P > 0.05), or Hp infection (r = 0.016, P > 0.05) was found. Primary DGR could cause gastric mucosal lesions manifested mainly as hyperemia and bile-stained gastric antral mucosa under endoscopy and the gastric antral intestinal metaplasia histologically in children. There was no significant correlation between DGR and gastric mucosal inflammatory infiltration. DGR had no relevance to Hp infection and intragastric acidity. We conclude that DGR is probably an independent etiological factor and might play a synergistic role in the pathogenesis of gastric mucosal lesions along with gastric acid and Hp infection.
    Zhonghua er ke za zhi. Chinese journal of pediatrics 04/2008; 46(4):257-62.
  • [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the clinical manifestations and endoscopic features of abdominal type Henoch purpura in children and improve the diagnostic level. Retrospective review was made on the clinical, endoscopic and histopathological features of 57 cases of children with Henoch purpura abdominal type who had been hospitalized from Jan. 2002 to May 2007. Upper gastrointestinal endoscopy was performed in all cases. All the cases had various digestive system symptoms without cutaneous purpura before endoscopy. Mucosal specimens were taken from sinus ventriculi and duodenum for histopathological analysis. Helicobacter pylori (H.pylori) infection was identified by rapid urease test and histology, and diagnosis of H.pylori infection was made when both were positive. The common gastrointestinal symptoms of Henoch purpura were abdominal pain (46 cases), vomiting (32 cases), hematochezia (11 cases), diarrhea (4 cases) and abdominal distention (1 case). Three cases had arthralgia and joint swelling. The main laboratory findings were increased peripheral white blood cells (33 cases, 57.9%), 1/5 of cases had elevated C reactive protein (CRP), low serum albumin and seroperitoneum. Endoscopy demonstrated the damages to the mucosa, which varied from congestion, edema, petechia and ecchymosis (37 cases, 64.9%) to erosive and multiple ulcers (14 cases, 24.6%), granulation of mucosa in descendent duodenum (4 cases, 7.0%), and diffuse hemorrhage of mucosa (2 cases, 3.5%). The upper gastrointestinal endoscopy showed that the commonest and most serious position involved was the descendent duodenum (55 cases, 96.5%), followed by duodenal bulb (32 cases, 56.1%) and stomach (18 cases, 36.1%), esophagus was less involved (1 case, 1.8%). Histological manifestations showed swollen vascular endothelial cells of capillary vessels and small blood vessels, fibrotic necrosis of small vessels and bleeding, diffuse perivascular lymphocytic and neutrophilic infiltration and nuclear debris in mucosa and submucosa. Three cases (5.3%) were found infected with H. pylori. In 49 cases (86.0%) cutaneous purpura appeared 1 - 7 days after endoscopy. Eight cases had no cutaneous purpura until they left hospital. Two cases were lost to follow up and 6 cases (10.5%) remained free from cutaneous purpura were followed up until now (1 - 5 years). Descending duodenum is the commonest and most serious position of upper gastrointestinal tract involved in Henoch purpura. Upper gastrointestinal endoscopy with the mucosal biopsy are useful for the early diagnosis of Henoch purpura.
    Zhonghua er ke za zhi. Chinese journal of pediatrics 12/2007; 45(11):814-7.
  • [Show abstract] [Hide abstract]
    ABSTRACT: Many clinical studies indicated that Helicobacter pylori (Hp) strains rarely acquired resistance to amoxicillin but easily to clarithromycin and metronidazole. However, it was unclear whether the antibiotic resistance of Hp strains was induced or passively selected during long-term or frequent treatment with metronidazole, clarithromycin and amoxicillin. To compare the propensity of acquired resistance to antibiotics, Hp strains were exposed to amoxicillin, clarithromycin and metronidazole in vitro in this study. All Hp strains were clinical isolates, derived from biopsy specimens of patients taken during endoscopy in the Affiliated Children's Hospital, Zhejiang University School of Medicine from December 2004 to July 2005. To seek susceptible strains, the minimum inhibitory concentrations (MICs) of the three antibiotics were determined by using Epsilometer test (E-test) method. In vitro induction was carried out on serially doubling concentrations of antibiotics incorporated into agar. Isolates were also transferred at least three times on antimicrobial agent-free medium, followed by a redetermination of the final MICs to assess the stability of the selected resistance. 7 strains were exposed to antibiotics in vitro. After 6 - 17 passages on antibiotic plates, 7 and 3 strains respectively acquired resistance to metronidazole and clarithromycin, while none of the strains were resistant to amoxicillin. The inductive folds were different among three groups: 8 - 128 folds in metronidazole group; 1 - 256 folds in clarithromycin group; 2 - 16 folds in amoxicillin group. After three transfers on antimicrobial agent-free medium, the MICs decreased significantly in amoxicillin group (P < 0.05) but had no change in metronidazole group and clarithromycin group (P > 0.05). The metronidazole resistance in Hp was easily selected. Strains resistant to clarithromycin could be selected, but the amoxicillin resistance could not be selected after in vitro induction for Hp isolated from children. The correlation between in vitro and in vivo outcomes suggests that acquired resistance was the main cause for the resistance in Hp strains. The laboratory results of in vitro antibiotic induction could help predict the actual rate of resistance and select appropriate antibiotics for treatment.
    Zhonghua er ke za zhi. Chinese journal of pediatrics 09/2007; 45(9):708-11.
  • [Show abstract] [Hide abstract]
    ABSTRACT: To enhance our understanding of pediatric Crohn's disease and improve diagnostic accuracy and therapeutic efficacy by characterizing the clinical picture and reviewing 10 years' clinical experience in diagnosis and treatment. Nine cases with active Crohn's disease diagnosed between 1996 and 2005, including 8 males and 1 female, aged 6 - 13 years, were reviewed. Clinical, radiologic, endoscopic and histological data as well as therapeutic results were analized. The mean interval from the onset of symptoms to the diagnosis was 10 months. The sites of involvement were both the small intestine and colon in 6, small intestine only in 3. Abdominal pain and diarrhea were the two most common gastrointestinal symptoms. The main extraintestinal manifestations were weight loss in 7, hypoalbuminemia in 5, mild anemia in 5, fever in 4 and hypocalcemia in 2. All the patients had undergone colonoscopy, and the findings included ulcerations, segmental lesions, cobblestone appearance, pseudopolyps and perianal abnormalities. Capsule endoscopic examination in one patient demonstrated the segmental distribution with typical longitudinal cleft-like ulcers and cobblestone appearance. Gastrointestinal barium meal X-ray examination was performed in 7 patients, the main findings were segmental strictures and abnormal mucosa. Histological examination of biopsy specimens mainly showed nonspecific chronic inflammation. Non-caseating granulomas were identifiable in 2 cases. Although there were many macroscopic and microscopic features supporting the diagnosis of Crohn's disease, no epithelioid granuloma could be found in surgical specimens of two patients. Treatment was given up by parents of 2 patients after the diagnosis was established. All the other 7 patients were treated with 5-acetylsalicylic acid, antibiotics and nutritional support during the acute phase. Corticosteroids were used in two patients. Long-term remission was achieved and maintained in 3 children, and in one of them medication could be discontinued and had no signs of disease activity at the end of the follow-up. Children and adolescents presenting with Crohn's disease commonly have weight loss and nutritional impairment, which may provide clues to the diagnosis. Appropriate formulation and higher dosage of 5-acetylsalicylic acid [30-50 mg/(kg x d)] may be effective in inducing and maintaining remission in pediatric Crohn's disease.
    Zhonghua er ke za zhi. Chinese journal of pediatrics 05/2007; 45(4):248-51.
  • [Show abstract] [Hide abstract]
    ABSTRACT: To study the incidence of viraemia and extraintestinal organ damage in children with acute rotavirus (RV) gastroenteritis. Eighty-three children with acute rotavirus gastroenteritis were hospitalized from October 2002 to March 2003, whose blood and fecal samples were obtained on admission. Rotavirus RNA (encoding the VP7 outer capsid protein) were detected in blood and fecal samples by nest reverse transcription-polymerase chain reaction (RT-PCR). According to the result of blood RV-RNA, the patients were divided into RV-RNA positive group and RV-RNA negative group. The differences between these two groups in the severity of gastroenteritis and extraintestinal organ damage were analyzed. Eighty-two of 83 stool samples from the children with rotavirus infection were positive for rotavirus RNA. Sixteen of 83 blood samples were positive for rotavirus RNA with a positive rate of 19.3%. The nucleotide sequence of cloned cDNAs, resembling part of the VP7 gene, was identical from paired blood and fecal samples. There were no significant differences between blood RV-RNA positive group and blood RV-RNA negative group in the rate and degree of fever, diarrhea, dehydration, metabolic acidosis, hypokalemia and myocardial damage (P>0.05); while the incidences of liver damage, rash, lower respiratory tract infection and the central nervous system involvement in the blood RV-RNA positive group were significantly higher than those in the blood RV-RNA negative group (P<0.05). Viraemia is present in the children with acute rotavirus gastroenteritis. Viraemia might be an important mechanism by which rotavirus spread to the extraintestinal sites resulting in organs damage.
    Zhejiang da xue xue bao. Yi xue ban = Journal of Zhejiang University. Medical sciences 01/2006; 35(1):69-75.
  • Zhong-yue Li, Fei-bo Chen, Jie Chen
    [Show abstract] [Hide abstract]
    ABSTRACT: To study the changes of gastric mucosal CD4(+) and CD8(+) T cells in Helicobacter pylori (Hp) infected children. Seventy nine patients with digestive tract symptoms were assessed by endoscopy, rapid urease test and histology. Forty four patients had Hp positive chronic superficial gastritis (Hp(+)CSG) and 35 patients had Hp negative chronic superficial gastritis (Hp(-)CSG). Gastric biopsy specimens were obtained from each patient. Peripheral blood samples were obtained from 33 patients (12 with Hp(+)CSG, 21 with Hp(-)CSG). Hp infection was identified by rapid urease test and histology. Hp infection was confirmed when a patient was positive for both of these tests. Four pieces of gastric antrum mucosal specimens were placed in Hank's balanced salt solution containing 1 mmol/L dithiothreitol (DTT) and 1 mmol/L ethylenediamine tetraacetic acid (EDTA). The specimens were treated with collagenase type I (120 U/ml) for three hours at 37 degrees C with agitation. The mononuclear cells were collected by removing undigested material and washed three times with RPMI 1640. Isolated gastic mononuclear cells were stained with CD3-FITC (fluorescein isothiocyanate), CD4-PE (R-phycoerthrin), CD8-PerCP (Peridinin-chlorophyll-alpha-protein) and measured by flow cytometry. Mucosal T lymphocytes were gated for the expression of CD3. Peripheral blood lymphocyte subsets were analysed by direct immunofluorescence. The percentage of isolated gastric mononuclear cells within the CD3 gate were 3.26 +/- 1.98 in Hp(-)CSG, 4.37 +/- 1.97 in Hp(+)CSG. Relative CD4(+)(%), CD8(+)(%) and CD4(+)/CD8(+) of the CD3(+) cells respectively were 23.74 +/- 10.37, 47.04 +/- 12.00, 0.52 +/- 0.23 in Hp(-)CSG group, 40.28 +/- 11.35, 27.91 +/- 8.84, 1.55 +/- 0.52 in Hp(+)CSG group. CD4(+)(%), CD4(+)/CD8(+) in Hp(+)CSG group were significantly higher than those of Hp(-)CSG group and CD8(+)(%) was lower than those of Hp(-)CSG group (P < 0.01). There were no significant differences in peripheral blood T lymphocyte subsets between the two groups. The difference of gastric T lymphocyte response between Hp(+)CSG and Hp(-)CSG in children indicated that the local cellular immune reaction may play a critical role in the pathogenesis of Hp infection.
    Zhonghua er ke za zhi. Chinese journal of pediatrics 07/2005; 43(6):453-6.
  • [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the prevalence of Helicobacter pylori (H. pylori) resistance to clarithromycin (CLM) in children and to demonstrate the correlation of 23S rRNA gene mutation to clarithromycin resistance of Helicobacter pylori isolates. Totally 108 clinical strains of H. pylori were isolated from gastric biopsy specimens obtained from children who underwent endoscopy during the period from October 2002 to January 2004 in Children's Hospital Affiliated to Medical College of Zhejiang University. H. pylori was identified by morphology and biochemical tests after culture. Clarithromycin susceptibility of H. pylori isolates was determined by both E-test and two-fold agar dilution method. A strain was considered resistant when the MIC was defined as >or= 1 microg/ml. Genome DNAs of the 108 isolates were extracted and prepared for PCR to detect the corresponding gene in the V domain of the 23S rRNA. The amplified fragments were recognized and analyzed by restriction fragment length polymorphism (RFLP) when an additional restriction site is created by the mutation. The PCR products of all sensitive and resistant strains were digested with restriction enzyme BbsI and BsaI and were analyzed on a 1.5% agarose gel to discriminate different kinds of mutant genotype. Sixteen of 108 isolates of H. pylori were resistant to clarithromycin by the agar dilution method and E-test method in clinical isolates from children, and the CLM resistance rate was 14.8% (16/108) with MICs ranging from 1 microg/ml to 128 microg/ml. Comparison of results of the two methods showed that these two methods were quite consistent in determination of susceptibility and resistance. The target fragment 425 bp in length containing 23S rRNA corresponding gene was successfully amplified. An A2144G mutation digested with BsaI was detected in 13 resistant isolates, but an A2143G mutation digested with BbsI in only 3 among all 16 clarithromycin resistant strains. None of the sensitive isolates was cleaved by either BsaI or BbsI enzyme, indicating that there was no mutation on them. It was also found that all the fragments from the resistant strains were not completely digested, and 425 bp uncut fragments were also visible and showed three bands indicating that they were heterozygotic strains with a mixture of wild-types and A-->G genotypes. In addition, in this study, no statistically significant difference between mutations at positions 2143 and 2144 with respect to the MIC was observed (r = 0.035, P > 0.05). A high prevalence of clarithromycin-resistant H. pylori strains were detected among strains isolated from Chinese children studied. The 23S rRNA gene mutation at positions A2143G and A2144G plays an important role in clarithromycin resistance of H. pylori and A2144G mutation is the predominant finding among the resistant strains.
    Zhonghua er ke za zhi. Chinese journal of pediatrics 11/2004; 42(11):850-3.
  • [Show abstract] [Hide abstract]
    ABSTRACT: To investigate the prevalence of Helicobacter pylori (Hp) resistant to clarithromycin, amoxicillin and metronidazole in children. A total of 44 Hp clinical isolates were cultured from children patients with Hp gastritis and peptic ulcer who underwent gastroscopy during the period from October 2002 to November 2003 in Children's Hospital affiliated to Medical College of Zhejiang University. Nineteen of the patients were girls and 25 boys. The mean age was 8.66 +/- 2.66 years (3 approximately 14 years). The susceptibilities of the 44 Hp strains to clarithromycin, amoxicillin and metronidazole were tested by agar dilution test to determine minimum inhibitory concentration (MIC)(50), MIC(90) and resistance rates were also calculated. Among the 44 Hp strains isolated from children, 8, 4, and 14 strains were resistant to clarithromycin, amoxicillin and metronidazole and the resistant rate was 18.2% (8/44), 9.1% (4/44) and 31.8% (14/44), with MICs for all strains ranging from < 0.125 microg/ml to 64 microg/ml, < 0.125 microg/ml to 64 microg/ml and < 0.125 microg/ml to 128 microg/ml, respectively. MIC(50) and MIC(90) of clarithromycin, amoxicillin and metronidazole were < 0.125 microg/ml, 8 microg/ml; < 0.125 microg/ml, 0.5 microg/ml; 0.5 microg/ml, 128 microg/ml, respectively. The prevalence of Hp resistant to clarithromycin was higher in children than that in adults, while to metronidazole was lower than that in adults with high MICs (32 - 128 microg/ml) and MIC(90) (128 microg/ml) of metronidazole for resistant isolates. Three multidrug resistant strains (6.8%) were simultaneously resistant to these three antibiotics. The prevalence of Helicobacter pylori resistant to metronidazole was high in children, and the rate of resistance to clarithromycin was higher than that isolated from adults. Amoxicillin-resistant strains were now found, and multidrug resistant strains which resistant to the three antibiotics also emerged.
    Zhonghua er ke za zhi. Chinese journal of pediatrics 10/2004; 42(10):769-71.
  • Zhong-yue Li, Jin-gan Lou, Jie Chen
    [Show abstract] [Hide abstract]
    ABSTRACT: To improve the clinical diagnostic standard and explore the mechanism of multiple clinical manifestation of Epstein-Barr virus (EBV) infection by studying the primary symptom and related disease spectrum in EBV infected children. The primary symptom, disease spectrum and prognosis of 190 EBV infected children whose serum EBV-VCA-IgM was positive detected by enzyme-linked immunosorbent assay (ELISA) were retrospectively reviewed. The primary symptoms of EBV infection were diverse, the most common primary symptom was fever (66.8%), and followed by cough (14.2%), skin eruption (7.9%), lymphadenopathy (5.3%), eyelid edema (3.2%), pharyngalgia (1.6%), cardiac arrhythmia (1.6%), convulsion (1.6%), arthralgia (1.0%), gross hematuria (0.5%), etc. Most systems and organs were involved in the disease, including liver, spleen, lymph nodes, kidney, heart, lung, bone marrow, brain etc., which made the disease spectrum diverse. The most common disease caused by EBV infection was respiratory tract infection (40.5%), followed by infectious mononucleosis (17.9%), Kawasaki disease (6.3%), idiopathic thrombocytopenic purpura (5.8%), viral myocarditis (2.6%), viral encephalitis (2.6%), hemophagocytic syndrome (1.6%), rheumatoid arthritis (1.0%), acute lymphadenitis (1.0%), facial neuritis (1.0%), Evans syndrome (0.5%), systemic lupus erythematosus (0.5%), subacute necrotizing lymphadenitis (0.5%), non-Hodgkin's lymphoma (0.5%), acute aplastic anemia (0.5%), infantile hepatitis syndrome (0.5%), etc.; 9.5% of patients were ultimately diagnosed as EBV infection after long-term fever, and 10% of patients suffered from mixed infection. The prognosis of EBV infection was different due to involvement of different systems and organs. One patient died of hemophagocytic syndrome. The systems and organs impaired by EBV infection in children were diverse, and almost all the systems and organs were involved. Pediatricians should comprehensively analyze the clinical data and order corresponding laboratory examinations early to make the correct diagnosis and reduce the misdiagnosis rate and to treat appropriately.
    Zhonghua er ke za zhi. Chinese journal of pediatrics 02/2004; 42(1):20-2.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Background: Antimicrobial resistance in Helicobacter pylori (H. pylori) is an increasing serious problem, and the development of methods for detecting the resistance and the constant surveillance of both prevalence and evolution of H. pylori resistance in children would greatly improve the selection of antibiotics used to treat gastroduodenal infection with this organism. This study was designed to investigate the prevalence of H. pylori resistance to clarithromycin, metronidazole and amoxicillin isolated from pediatric patients in China. Methods: A total of 44 H. pylori isolates from pediatric patients with gastritis and peptic ulcer undergoing endoscopy were cultured during the period of October 2002 to November 2003 at Children's Hospital, Zhejiang University School of Medicine, Hangzhou, China. The susceptibilities of the 44 H. pylori isolated strains to clarithromycin, metronidazole and amoxicillin were tested by the agar dilution test to determine the minimum inhibitory concentration (MIC). Results: The range of MIC was as follows: clarithromycin 0.125-64 μg/ml; metronidazole

Publication Stats

12 Citations

Institutions

  • 2004–2007
    • Zhejiang University
      • • School of Medicine
      • • First Affiliated Hospital of Medical College
      Hangzhou, Zhejiang Sheng, China