Evaluation of the effects of different 14C-urea breath test products in the diagnosis of Helicobacter pylori infection / 中华消化杂志

Objective:To evaluate the effects of the cassette 14C-urea breath test kit, scintillation sampling bottle (solid-state scintillation method) and liquid scintillation 14C-urea breath test kit in the diagnosis of Helicobacter pylori ( H. pylori) infection. Methods:From January 7 to October 28, 2020, 239 patients were enrolled who visited Renji Hospital Affiliated to Shanghai Jiaotong University School of Medicine, the Second Affiliated Hospital of Zhejiang University School of Medicine and the First Affiliated Hospital of Nanchang University. All subjects first received 14C-urea breath test.Within >1 to <7 days after gas collection, mucosal tissues were taken under gastroscopy for gold standard test, including biopsy and rapid urease test (RUT). If both biopsy and RUT indicated H. pylori positive, the result of gold standard test was H. pylori positive, and if both were negative, the result of gold standard test was H. pylori negative. If the results of biopsy and RUT were inconsistent, they were not included in the subsequent analysis. Based on the results of gold standard test, the sensitivity, specificity, accuracy, positive predictive value and negative predictive value of the cassette 14C-urea breath test kit, scintillation sampling bottle, and liquid scintillation 14C-urea breath test kit in the diagnosis of H. pylori infection were analyzed. The safety of the test was evaluated by whether there were any adverse events during the test. Descriptive methods were used for statistical analysis. Results:Among the 239 subjects, 12 cases did not complete the test, 227 subjects finally completed the test. The test completion rate was 95.0% (227/239). No.008 patient was only included in the analysis of cassette 14C-urea breath test kit and scintillation sampling bottle because of lacking the result of liquid scintillation breath test. The results of gold standard test showed that among 227 patients, 87 cases were H. pylori positive, 118 cases were H. pylori negative. The results of biopsy and RUT were inconsistent in 22 cases, so they were not included in the subsequent analysis. Excluding No.008 patient, the results of gold standard test showed that 86 cases were H. pylori positive and 118 cases were negative. Based on the results of gold standard test, the sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of cassette 14C-urea breath test kit, scintillation sampling bottle, and the liquid scintillation 14C-urea breath test kit in the diagnosis of H. pylori infection were 91.9%, 100.0%, 96.6%, 100.0% and 94.4%, respectively; 95.4%, 97.5%, 96.6%, 96.5% and 96.6%, respectively; and 96.5%, 99.2%, 98.0%, 98.8% and 97.5%, respectively. Only one adverse event (right upper abdominal pain after eating) occurred. Combined with the patients condition, the adverse event was determined as the onset of chronic cholecystitis and it might not be related to the test medication. Conclusions:Cassette 14C-urea breath test kit, scintillation sampling bottle, and liquid scintillation 14C-urea breath test kit have reliable performance, good safety, and high sensitivity, specificity and accuracy in the diagnosis of H. pylori infection, which are worthy of clinical application.

Study of Prevalence and Serodiagnosis of Dengue Fever in Febrile Patients Attending a Tertiary Care Hospital.

Dengue is a mosquito-borne viral infection found in tropical and sub-tropical regions around the world and has emerged as a significant threat and burden to public health systems. The infection is transmitted by the bite of an infected female mosquito- Aedes aegypti. Dengue viral infection may be asymptomatic or may give rise to undifferentiated fever with or without other associated clinical manifestations, namely, Dengue Fever (DF), Dengue Haemorrhagic Fever (DHF) or Dengue Shock Syndrome (DSS). The present study is conducted to evaluate the prevalence and serodiagnosis of Dengue fever among patients with acute febrile illness, provide useful guidance to clinicians for early diagnosis and prevention of untoward complications of dengueMETHODSThis was a retrospective descriptive study conducted for a period of one year in a tertiary care hospital from January 2019- December 2019. Blood samples collected from 1905 clinically suspected cases of dengue fever and serum were separated and tested for detection of Dengue NS1 antigen, Dengue specific IgM antibody and IgG antibody by using Dengue Day 1 test kit (procured from J. Mitra & Co. Ltd, India). Test was performed and results were interpreted as per manufacturer manual.RESULTSOut of 1905 serum samples tested, 273 were positive for dengue and 1632 were negative, with seropositivity was 14.33%. Out of 273 dengue positives, 202 (73.6%) were positives for dengue specific NS1 Antigen, 50 (18.3%) were positives for dengue specific IgM and 14 (5.12%) were positives for dengue specific IgG and 8 (2.93%) were positives for both IgM and IgG. Out of 273 positives cases of dengue, 158 (57.8%) were males and 115 (42.12%) were females. Majority of the patients tested positive were in the age group of 21-30 yrs. (28.2%).CONCLUSIONSDengue cases occur throughout the year with more positives in Jun-October. The incidence of dengue cases was higher in males and in children and in young adults. Early laboratory diagnosis of dengue fever among patients with acute febrile illness is essential to prevent dengue related complications.

Cost-Benefit Analysis of Malaria Chemoprophylaxis and Early Diagnosis for Korean Soldiers in Malaria Risk Regions

BACKGROUND: Chemoprophylaxis has been used to prevent malaria among soldiers and secondary transmission, as it effectively facilitates a decline in disease occurrence and secondary prevention. However, poor compliance and decreased risk of exposure to malaria necessitate that control strategies be reestablished. METHODS: To predict the incidence of malaria according to a control strategy, we proposed a mathematical model for its transmission using epidemiological data from 2010 to 2012. The benefit component included in the analyses was the averted cost with each control strategy, and the cost components were the cost of implementing chemoprophylaxis and early diagnosis. RESULTS: The chemoprophylaxis regimen with hydroxychloroquine sulfate and primaquine was Intervention 1, the regimen with primaquine only was Intervention 2, and diagnosis with a rapid diagnostic test (RDT) kit within 5 days of fever was Intervention 3. The simulation indicated that the combined control program with chemoprophylaxis and early diagnosis would be the most effective strategy, whereas sole early diagnosis would be the least effective strategy. However, the cost-benefit ratio of chemoprophylaxis was less than Intervention 1, irrespective of the varying range of chemoprophylaxis compliance, and that of early diagnosis was more than Intervention 1, regardless of the varying early diagnosis rate and demand for the RDT kit. Although chemoprophylaxis would be more effective at reducing the incidence of malaria than early diagnosis, it is less economical due to the higher cost. CONCLUSION: Our results support the introduction of early diagnosis with a RDT kit to control malaria in the Republic of Korea Army.

Clinical evaluation of a rapid diagnostic test kit for detection of canine coronavirus / 대한수의학회지

Canine coronavirus is a single-stranded RNA virus that causes enteritis in dogs of any age. Coronaviral enteritis is seldom definitively diagnosed, since it is usually much less severe than many other types of enteritis and is self-limiting. Conventional diagnostics for the canine coronaviral enteritis such as polymerase chain reaction (PCR), virus isolation, and electron microscopic examination are inappropriate for small animal clinics due to the complicated experimental processes involved. Therefore, a commercially available lateral flow test kit based on chromatographic immunoassay techniques was tested to evaluate its performance as a first-line diagnostic test kit that could be used in clinics. The coronavirus antigen test kit detected canine coronavirus-infected dogs with 93.1% sensitivity and 97.5% specificity. The detection limit of the test kit was between 1.97 × 10⁴/mL and 9.85 × 10³/mL for samples with a 2-fold serial dilution from 1.25 × 10⁶ TCID₅₀ (TCID₅₀, 50% tissue culture infectious dose). Additionally, the test kit had no cross-reactivity with canine parvovirus, distemper virus, or Escherichia coli. Overall, the commercially available test kit showed good diagnostic performance in a clinical setting, with results similar to those from PCR, confirming their potential for convenient and accurate use in small animal clinics.

Comparison of five methods for the detection of fungal infections in vaginal secretions / 国际检验医学杂志

Objective To compare the similarities and differences of the five detection methods used in the detection of fungi in vaginal secretions,and find the most sensitive、the most specific、the fastest、the most cost effective and the simplest method used in the detection of fungi in vaginal secretions.Methods A total of 442 patients were selected from the Department of Gynecology of Shenzhen OCT Hospital from May 2016 to August 2016.The vaginal secretion of 442 specimens was detected by using the methods of fungi culture、saline and KOH suspension method,Gram stain,Wright''s stain and Vaginitis Multi Test Kit.In these five methods,Fungi culture were using as gold standard to evaluate the specificity,sensitivity,negative predictive value,positive predictive value and accuracy of the other four methods.Results Using the fungus culture method to detect 442 cases of vaginal secretion,we found the positive rate of mycotic infection was 34.8%(154/442).Compared with the fungi culture method,the Specificity of saline and KOH suspension method was 97.9%,the sensitivity was 64.9%,the negative predictive value was 83.9%,the positive predictive value was 94.3% and the accuracy was 86.4%;the Specificity of Gram stain was 96.5%,the Sensitivity was 83.1%,the negative predictive value was 91.4%,the positive predictive value was 92.7% and the accuracy was 91.8%;the Specificity of Vaginitis Multi Test Kit was 84.7%,the Sensitivity was 46.8%,the negative predictive value was 74.8%,the positive predictive value was 62.0% and the accuracy was 71.5%;the Specificity of Wright''s stain was 96.9%,the Sensitivity was 78.6%,the negative predictive value was 89.4%,the positive predictive value was 93.1% and the accuracy was 90.5%.Conclusion Gram stain could be the most sensitive and specific method in the four methods,with highest accuracy,and the the fastest,the most cost effective and the simplest method for the detection of fungi in vaginal secretions.The accuracy of detecting fungi in vaginal secretions could be improved by the combination of Gram stain method in clinical work.

Comparative evaluation of Immunochromatographic Assay for screening Hepatitis C among blood donors in a rural teaching hospital, Sangareddy

Background: HCV is a blood borne virus. Mainly HCV infection attacks the liver and can cause chronic Hepatitis, liver cirrhosis (27%) and liver cancer (25%) and shows significant mortality and morbidity. Aim: The present study was to assess ICT kit used in the preliminary screening process of HCV infection among blood donors in a rural teaching hospital, Sangareddy. Nagababu Pyadala, Prudhvi Chand Mallepaddi, Rajaneesh Borugadda, Soumendra Nath Maity, Rohit C. P., Rathnagiri Polavarapu. Comparative evaluation of Immunochromatographic Assay for screening Hepatitis C among blood donors in a rural teaching hospital, Sangareddy. IAIM, 2016; 3(6): 152-156. Page 153 Materials and methods: In this study, 1050 number of blood units were collected from donors containing both voluntary and replacement donors for a period of one year from January 2015 to December 2015. 1050 donors were tested for HCV by using ICT kit and ELISA method. Results: We found 4 out of 1050 subjects tested positive for HCV by using ICT kit and conformed by ELISA method. Conclusion: The present study concluded that the overall performance of the rapid ICT kit for HCV was equally sensitive to ELISA and yet they were cheap and quicker. It can be recommended that ELISA comparable rapid devices may be allowed to be used for preliminary screening of Hepatitis C especially, in remote areas or where cost is an issue.

Evaluation of performance of homocysteine test kit / 国际检验医学杂志

Objective To evaluate the performance of homocysteine(Hcy)test kit produced by a domestic company and to inves-tigate its feasibility in clinical application.Methods A series of methodological evaluation experiments including the accuracy,re-peatability,stability and linear range of the Hcy reagent kit were carried out on the Olympus Au640 biochemistry analyzer.Results The experiments showed that the relative biases of detection results of normal value quality control serum and pathological value quality control serum were 0.2% and 4.9%,respectively,which were far less than 15% of the reagent instruction.The intra-assay coefficients of variation(CV)of normal and pathological quality control serum were 2.6% and 2.3% respectively,which were less than 5% of the reagent instruction.While the inter-assay CV of normal and pathological quality control serum were 4.4% and 4.1% respectively,which were less than 10% of the reagent instruction.The experiments for the linear range evaluation showed that R 2 was 0.997 in the concentration range of 0 -66 μmol/L,which suggested that the correlation between expected value and measured value was very well.Otherwise,the slope rate b1 of 0.979 9 and the intercept b0 of 0.151 8 were both showed that the de-tection results of Hcy reagent were linear in the concentration of 0-66 μmol/L.Conclusion The performance of Hcy kit produced by a domestic company is very good in the performance indexes of accuracy,repeatability,stability,and linear range and suitable for the clinical application.

Nested-PCR and a New ELISA-Based NovaLisa Test Kit for Malaria Diagnosis in an Endemic Area of Thailand

Microscopy is considered as the gold standard for malaria diagnosis although its wide application is limited by the requirement of highly experienced microscopists. PCR and serological tests provide efficient diagnostic performance and have been applied for malaria diagnosis and research. The aim of this study was to investigate the diagnostic performance of nested PCR and a recently developed an ELISA-based new rapid diagnosis test (RDT), NovaLisa test kit, for diagnosis of malaria infection, using microscopic method as the gold standard. The performance of nested-PCR as a malaria diagnostic tool is excellent with respect to its high accuracy, sensitivity, specificity, and ability to discriminate Plasmodium species. The sensitivity and specificity of nested-PCR compared with the microscopic method for detection of Plasmodium falciparum, Plasmodium vivax, and P. falciparum/P. vivax mixed infection were 71.4 vs 100%, 100 vs 98.7%, and 100 vs 95.0%, respectively. The sensitivity and specificity of the ELISA-based NovaLisa test kit compared with the microscopic method for detection of Plasmodium genus were 89.0 vs 91.6%, respectively. NovaLisa test kit provided comparable diagnostic performance. Its relatively low cost, simplicity, and rapidity enables large scale field application.

Comparison of Two Commercial Screening Kits for Detection of Anti-HCV Antibody among Adult Patients in Osogbo, Nigeria.

Aims: A commercial rapid test kit for anti-Hepatitis C Virus (anti-HCV) detection was evaluated and compared for diagnosis of hepatitis C by detection of immunoglobulin G(IgG) antibodies against a third generation Enzyme Immunoassay(EIA) as gold standard. Methodology: A total of 560 patient serum samples were subjected to rapid screening with rapid test (immunochromatographic) strip supplied by Global Diagnostics and commercially prepared IgG capture EIA by DIA.PRO, Italy. Results: Of the 560 samples, anti HCV was detected in 31(5.54%) by ELISA, whereas only 17(3.04%) by strip method. This gives 100% specificity as no false positive was observed, but with 68.8% sensitivity. The number of false negative results was 14. The positive and negative predictive values were 100% and 97.42% respectively. Conclusion: The result pattern shows that sensitivity is compromised. It is therefore recommended that third generation ELISA is used for blood donors screening, to reduce transmission of hepatitis C virus through blood transfusion. When need arises to use strip for anti-HCV testing, such strip should be validated locally before its adoption because kits are directed against known range of strains of HCV and have minimum titer of antibody below which detection becomes impossible.

Prevalence of Dirofilaria immitis in Dogs in Shenyang, Northeastern China

In the present study, we first report the seroprevalence of Dirofilaria immitis in dogs in Shenyang, northeastern China. Sera from 528 randomly selected dogs were examined for D. immitis antigen using SNAP(R)4Dx test kit; 12.7% tested showed seropositive. No significant difference of infection was observed in different genders and breeds (P>0.05), but the difference was significant in different age groups and rearing conditions (P<0.05). The result suggested that the risk of exposure to D. immitis in dogs is high in Shenyang, and should be given attention.

Quantification of Der f 1 in houses of patients allergic to house dust mite, Dermatophagoides farinae, using a locally produced detection reagents.

Background: House dust mite (HDM) allergen quantification in house dust samples before and after the allergen elimination is one means of convincing the target population about the health benefits of allergen removal from their environment. Objective: To produce local reagents for quantification of Der f 1 (major allergen of Dermatophagoides farinae) in dust samples from houses of HDM allergic Thai patients. Methods: Recombinant Der f 1 was used for immunization of a BALB/c mouse for hybridoma production. Polyclonal antibody (PAb) to whole body extract of D. farinae was prepared from an immunized rabbit. A sandwich ELISA (MAb-allergen-PAb) was used, in comparison with the commercialized reagents (Indoor Biotechnology, UK), to quantify Der f 1 in dust samples. Results: Two hybridoma clones, Df1-1 and Df1-2, were established. Their secreted MAbs (MAbDf1-1 and MAbDf1-2, respectively) bound to the homologous antigen as well as native Der f 1 and a crude extract of D. farinae. Epitopes of MAbDf1-1 and MAbDf1-2 were located at amino acid residues 206NSQHYGISNYCQ217 and 283DYW---NSWD-WGDSG298 of Der f 1. MAbDf1-1 had higher affinity to Der f 1 than the MAbDf1-2. A sandwich ELISA (MAbDf1-1-allergen-PAb) and commercialized reagents (MAb1-allergen-MAb2 sandwich ELISA) were used in comparison for quantification of Der f 1 in 42 dust samples collected from bedrooms and living rooms of 21 houses of the HDM allergic patients. All of the 42 dust samples measured by both ELISAs had the Der f 1 levels higher than 2 mg per gram of fine dust which is the HDM allergy sensitizing level. In addition, Der f 1 levels in 41 samples (except 1 sample from a living room) measured by the MAbDf1-1-PAb and MAb1-MAb2 sandwich ELISAs were higher than 10 mg per g of dust which is the morbidity level of HDM allergen. The local sandwich ELISA showed a high coefficient correlation (r = 0.91) in measuring known amounts of recombinant and native Der f 1. The results indicate that the reagents produced in the present study can be used for measuring the environmental levels of HDM Der f 1. The assay can also be used for standardization of the HDM extract for monitoring patient's allergenic status or for immunotherapeutic purpose.

Arsenic content of drinking water in Mongolia / Монголын Анагаах Ухаан

Background: Population of a significant number of countries in the world use drinking water high in arsenic content. Asia is a leading region in the world by the endemic arsenic prevalence and countries such as India, Bangladesh, China and Taiwan have high prevalence of arsenic. The fact that in neighboring China, namely, in Inner Mongolia, the number of cases of neuropathy and skin cancer has been increasing, amplifies the necessity for such studies. It is essential to conduct further research in order to identify arsenic content in drinking water throughout the country.Goal: The survey aims at studying arsenic content in drinking water and mapping arsenic prevalence by aimags and soumsMaterials and Methods: The survey was conducted nationwide –21 aimags and urban areas, in total, arsenic content in drinking water was studied in 291 soums in 867 wells. Arsenic content was identified with a test kit developed by Mahidol University, Thailand. Results: Out of 867 well water samples from 21 aimags and Ulaanbaatar studied for the survey, 91 or 10.5% contained arsenic. Arsenic was found in well water of all aimags except Bulgan, Zavkhan, Orkhon, Selenge and Huvsgul aimags. Nationwide, average arsenic content in drinking water is 0.014+ 0.003mg/l. Highest arsenic content was found in Dornogobi (53.9%), Dundgobi (31%) and Sukhbaatar (27.3%) aimags. Although average arsenic content in drinking water in selected wells in Tuv, Gobisumber, Dornogobi, Gobi-Altai, Dornod, Sukhbaatar and Dundgobi aimags contains 1.2-5 times more arsenic than UST-900-92 standard and WHO recommended content. Out of all studied samples, water from well #3 in Khatanbulag soum, Dornogobi, contained 0.07mg/l arsenic which is the highest – 0.065mg/l more than UST-900-92 standard and WHO recommended content.Concliusions:1. Out of 867 well water samples 10.3% contained arsenic.2. Arsenic content in drinking water nationwide is 0.014+-0.003mg/l. The highest arsenic content is recorded in Khatanbulag soum, Dornogobi – 0.075mg/l.

EPIDEMIOLOGICAL STUDY OF INFLUENZA VIRUS INFECTIONS IN YANGON, MYANMAR

Although influenza is a highly contagious acute respiratory illness of global importance, little is known about the disease in tropical countries. An influenza survey was conducted in three sentinel sites in Yangon, Myanmar from September 2003 to December 2004. Throat or nasal swabs were collected from 616 patients with influenza-like symptoms and tested using rapid diagnostic test kits and virus isolation. Influenza B virus was detected in 6 patients from September to October, 2003. Influenza A viruses were detected in 133 patients from June to September, 2004, and the 51 influenza A viruses isolated from 72 specimens were all A⁄H3N2. Influenza virus infections occurred mainly in the rainy season in Yangon, Myanmar, but continuous ongoing influenza surveillance is needed.

COMPARISON OF PRELIMINARY DETECTION RESULTS OF SEVERAL TOXOPLASMA GONDII ELISA TEST KITS / 中国人兽共患病学报

Aim Five types of civil Toxoplasma gondii ELISA test kit were used to the detected specimen which proved to be the same, foreign-made test kit was used to examine the positive specimen given by these five types of test kit, as to make comparison about quality of test kit. Results IgG-ELISA A,B kits positive showing rates (sensitive)are all 60％ ,the corresponding rate between A&B is merely 50％ ,the specifics are 35％&90％. C, D,E kits' positive showing rates (sensitive)are 30 ％, 60 ％, 70 ％ the specifice are 75 ％, 54 ％, 87 ％. The result about examining the probes given by A, B, D, E kit :IgG corresponding rates are better, which are all more than 90％ ;IgM corresponding rates are all more than 60％. It turn out that, according to the civil conditions of ELISA test kit, we suggest that besides the quality being improved in, all kinds of test kit should be used combinatively, so as to avoid neglect and mistake on examination, and we should be cautious in examining.