Total Number Of Positive Results Research Articles

ДИАГНОСТИЧЕСКАЯ ЦЕННОСТЬ ОПРЕДЕЛЕНИЯ ОТДЕЛЬНЫХ СЕРОЛОГИЧЕСКИХ МАРКЕРОВ CHLAMYDIA PNEUMONIAE И MYCOPLASMA PNEUMONIAE ИНФЕКЦИЙ В КЛИНИЧЕСКОЙ ПРАКТИКЕ

Introduction. Mycoplasma pneumoniae (M. pneumoniae), Chlamydia pneumoniae (C. pneumoniae) are becoming one of the leading etiologic pathogens in the spectrum of respiratory tract pathology in children. Therefore, research in the field of increasing the effectiveness of early laboratory diagnosis of these infections is of particular relevance. Aim of research. To determine the diagnostic value of identifying different classes of immunoglobulins (IgG, IgA, IgM) in patients with acute and exacerbation of chronic diseases of the respiratory tract in comparison with a control group of children without respiratory manifestations. Materials and methods. In a retrospective study, a detection of specific antibodies of classes A, M and G to M. pneumoniae and C. pneumoniae was carried out in 848 children hospitalized for various respiratory diseases, as well as in 336 children referred for preventive examination as a control. The ELISA method was used for serological diagnostics. Results. The total number of positive results of the tested sera was 55% (38% and 17%, respectively) in the group with acute and chronic diseases, which confirms the high etiological significance of mycoplasma and chlamydial infections in the region. Analysis of cases of seropositivity depending on the age and variant of clinical manifestation of respiratory tract infection revealed significant differences. The largest number of seropositive samples was detected in the group of school-age patients – the percentage amounted to almost 39% for C. pneumoniae IgA and 33% for M. pneumoniae IgA. Conclusion. Accurate diagnosis of atypical infections is critical for timely administration of etiotropic therapy to prevent complicated and protracted respiratory diseases. The use of molecular diagnostic methods is a priority. The study of specific antibodies to C. pneumoniae, M. pneumoniae has an advantage for diagnostics in case of hard-to-reach localization of the focus of biomaterial collection for PCR (bronchitis, pneumonia) and protracted course of the infectious process. The greatest diagnostic value for confirmation of both C. pneumoniae and M. pneumoniae infections in children over 36 month of age have specific antibodies of class A; their determination should be necessarily included into the examination complex. An isolated study of class M antibodies can lead to loss of diagnosis in 2/3 of patients.

Analysis of the results of epizootic monitoring of viral diarrhea — a disease of mucous membranes in cattle in the Russian Federation according to the reporting of 4-vet for 2020

Relevance. The reproductive health of dairy cows is one of the top priorities in dairy farming. Viral diarrhea, a disease of mucous membranes in cattle, is one of the causes of impaired reproductive function on farms. The disease is widespread throughout the world and causes significant economic damage, which consists of a decrease in productivity, lack of offspring, impaired reproductive function of the broodstock, costs of treatment and specific prevention. The viral diarrhea virus has an immunosuppressive effect. Diagnosis is complicated by a “blurry” clinical picture due to the association of the virus with other respiratory-intestinal viruses and the addition of a secondary bacterial infection, as well as the presence of a persistent form of infection. The diagnosis requires the analysis of clinical and epizootic data, pathological changes and a combination of several methods of laboratory diagnostics. An important link in the prevention and recovery of herds is the conduct of epizootic monitoring and analysis of its results.Methodology. The assessment of the epizootic situation for viral diarrhea, a disease of mucous membranes in cattle in the Russian Federation for 2020, was carried out based on the results of the analysis of information obtained from annual reports provided by state veterinary laboratories in the FSBI CNMVL in the form of 4-vet (annual).Results. Based on the results of the epizootic monitoring, it can be concluded that the viral diarrhea virus is widely circulating in the livestock farms of the Russian Federation. In 2020, positive results were recorded in all federal districts of the Russian Federation (in 33 subjects), except for the Far Eastern Federal District. The most difficult epizootic situation is in the North Caucasus Federal District and the Central Federal District (38% and 29% of the total number of positive results, respectively).

Analysis of BRCA1 and BRCA2 genes mutations in breast cancer patients in an experiment

Aim. To assess the presence of mutations based on the analysis of the prevalence of polymorphisms in the BRCA1 and BRCA2 genes in patients admitted to the Republican clinical Oncology dispensary of the Ministry of Health of the Republic of Bashkortostan with breast cancer.
 Methods. 137 patients with breast cancer aged 25 to 80 years underwent molecular genetic testing to detect BRCA1 and BRCA2 mutations by using allele-specific real-time polymerase chain reaction. Venous blood from 105 healthy donors was used as a control group.
 Results. The study of genetic modifiers of cancer risk for BRCA1 and BRCA2 mutation carriers revealed mutations in the genes BRCA1 185delAG, 4153delA, 5382insC, T300G and BRCA2-6174 del T, which help identify genetic susceptibility to breast cancer (NSCLC). The most common form of genetic variation in patients with breast cancer was 5382insC mutation in BRCA1 gene, which was 14.59% of the total number of examined patients and 90% of the total number of positive results. BRCA1 and BRCA2 genes mutations lead to producing truncated protein, which cannot properly perform its functions and ensure DNA cell stability.
 Conclusion. Considering high breast cancer risk in BRCA1 and BRCA2 genes mutations carriers, our results show the advisability of including screening for 5382insC, 4153delA and T300G mutations in the BRCA1 gene to the screening programs for determining the risk of breast cancer.

Implementation of Clostridium difficile Algorithm for Reduction of Inappropriate Testing in a Community Hospital

Introduction: Our hospital has a C. diff Infection (CDI) Stool Collection Algorithm (figure 1) in place to promote effective testing. In the previous year, data showed that there was an increase in stool samples collected more than 24 hours after order was placed. This delay in collection is likely due to lack of watery bowel movements since the order was placed. Any positive results from these orders are likely false positive. This leads to unwarranted treatment and inaccurate labeling of a hospital acquired infection if positive more than 48 hours after admission. Methods: CDI Stool Collection Algorithm was posted at all nursing stations and educational sessions were held. Message explaining the collection algorithm including a request to reevaluate the necessity of the order was sent to providers of patients with a C. diff order uncollected for more than 24 hours.1061_A Figure 1. Clostridium difficile Infection Stool Collection Algorithm1061_B Figure 2. Comparison of order breakdown during comparison and intervention period. Orders collected over 24 hours decreased (p=0.001)Results: Data was retrieved from the hospital database for the time period of this study and the corresponding time period last year for comparison. Last year, a total of 896 C. diff tests were ordered. This year, a total of 688 C. diff tests were ordered. This decrease is statistically significant with a p value of 0.002. Therefore, the interventions of implementing the collection algorithm led to more appropriate ordering (figure 3). Last year, the total number of C. diff orders collected after 24 hours was 84 and after the intervention this year, it was 34. The reduction was statistically significant with a p value of 0.001. This could be a reflection of the educational messaging system. (figure 2). The total number of positive results occurring from orders collected more than 24 hours from placement of order was 7 last year and it was 1 this year. There was no statistical difference between these numbers (p value = 0.15). The percentage was however reduced in half (8 to 4% of total results). Hospital acquired infection total number and rate were unchanged. Conclusion: This intervention may have led to more appropriate testing for CDIs through implementation of the CDI Algorithm and educational sessions. This was demonstrated in an overall decrease in orders. A reduction in collection of orders pending for 24 hours or more was achieved; through educational message system if deemed clinically appropriate. Despite this reduction, positive results from these collections were not reduced statistically and may not have led to improvement of unwarranted treatment of carrier patients.1061_C Figure 3. Comparison of Total C. Diff orders during comparison and intervention period (p=0.002)

Total Antibiotics — A New Possible Alternative for the Screening of Coccidiostat Residues in Poultry Meat

Abstract The Total Antibiotics test is a microbial inhibition test which has been recently introduced for the detection of antibiotics in meat. The aim of this study was to determine whether it would be suitable for the detection of coccidiostats in poultry meat. A comparison with the Premi®Test was assessed also for the suitability of the detection of coccidiostats in poultry meat. A selection of poultry meat samples of different organ parts were assessed with 14 samples from Slovakian farms that had previously been tested for coccidiostats by the Veterinary and Food Institute in Košice. In addition, another 8 samples from varied Slovakian supermarkets such as Lidl, Billa and Tesco with samples of chicken or duck meat, were tested. Each prepared sample was added to the Total Antibiotics kit tubes and incubated. The samples from all sources showed a mixture of positive and negative results for the detection of coccidiostats. For the Premi®Test, the samples used the same extraction procedure as the Total Antibiotics, placed in Premi®Test kit tubes and incubated. The Premi®Test demonstrated a mixture of positive and negative results, as similar to the Total Antibiotics for coccidiostats in the poultry farm samples. However, the Premi Test revealed many more negative results for the supermarket sources compared to the Total Antibiotics. Therefore, based on the total number of positive results, we concluded that Total Antibiotics is more sensitive for the detection of coccidiostats in poultry meat, but depending on the source of the samples, both Total Antibiotics and Premi®Test had either similar or opposite results for the detection of coccidiostats.

Su1145 Detection of Helicobacter pylori and Antibiotic Resistance Using a Molecular Genetics-Based Approach in Human Faecal Samples

Purpose: Diagnosing and treating H. Pylori infection is important for the management of peptic ulcer disease and gastric cancer. The purpose of this study is to compare the sensitivity and effects of H. Pylori detection by pathology and by HP MPCR. Methods: Between March 2011 and Oct 2014 in a clinical practice in New Jersey, 6943 patients suspected of having an H. Pylori infection underwent gastroscopy with biopsies.When the pathology was negative for H. Pylori, the specimen was tested for H. Pylori by HP MPCR from TZAM Diagnostics. The positive results recorded during the specified time period were grouped into the following categories: Pathology (the positive results determined only by pathology), HP MPCR (the positive results determined only by HP MPCR), and Total Positive (the total number of positive results determined by both methods). Results: Out of the 6943 patients, 2456 (35%) total patients tested positive for H. Pylori: 14% (1001) by pathology and 21% (1455) by HP MPCR. Furthermore, all three result categories Pathology, HP MPCR, and Total Positive reveal a decline in the incidence of H. Pylori infection from 2011 to 2014. The incidence of H. Pylori by pathology decreased from 15.8% in 2011 to 13.5% in 2014 (r = -0.891) at a rate of -0.89% per year. The incidence of H. Pylori by HP MPCR decreased from 30.3% in 2011 to 14.0% in 2014 (r = -0.978) at a rate of -5.4% per year. The total incidence of infection (taking both pathology and HP MPCR results into account) decreased from 46.1% in 2011 to 27.6% in 2014 (r= -0.975) at a rate of -6.3% per year (Figure 1). Conclusion: The data demonstrates that HP MPCR is useful in tandem with pathological detection, capturing an additional 21% of the study's population. Assuming a fixed patient population, the incidence of H. Pylori appears to be declining in this clinical practice. However, detection by HP MPCR indicates a much sharper decline in the incidence of H. Pylori infection (-5.4% per year) than detection by pathology (-0.89%). This trend can potentially be explained by the accuracy of HP MPCR detection. Because HP MPCR captures infected patients in addition to those captured by pathological examination, more patients can be treated for the infection, contributing to a general decline in positive H. Pylori cases. The data analysis of this population suggests that utilizing HP MPCR is a potential step toward the eradication of H. Pylori infection.

Evaluation of an Abbreviated Protocol for Cytomegalovirus pp65 Antigenemia Testing

The cytomegalovirus antigenemia assay remains a useful tool for monitoring reactivation among transplant recipients. In this study, we compared protocols using direct lysis of small-volume, whole blood (WB) samples vs peripheral blood leukocyte (PBL)-enriched fractions. Of 363 evaluable samples, 51 (14.0%) were positive by one or both methods. Sensitivity, specificity, and negative and positive predictive values were similar (76%, 99%, 96%, and 95% vs 71%, 100%, 96%, and 100% for the WB and PBL methods, respectively). Stratification of qualitative results by WBC count revealed comparable detection rates by each method, although the total number of positive results from leukopenic samples was significantly lower than from nonleukopenic samples (P= .04). Correlation between quantitative results was high, yet the degree of clinical agreement was suboptimal. We conclude that the small-volume, WB lysis method yields results statistically comparable to that of a PBL fractionation method but with fewer technical steps and less complexity.

Evaluation of the MicroFoss system for the detection of Listeria species in environmental samples

The MicroFoss system was evaluated for its ability to detect Listeria species in environmental samples. The sensitivity and specificity of the MicroFoss were determined in relation to a standard culture method for Listeria detection. The sensitivities of both the MicroFoss and standard culture methods were similar (88.4%—MicroFoss, 90.7%—Culture) based on the total number of positive results obtained by both methods. The MicroFoss system detected Listeria spp. in 12 samples, which were not detected by culture, and the culture method detected Listeria spp. in 15 samples, which were not detected by the MicroFoss method. This was likely due to uneven distribution of low levels of Listeria organisms in the split sponge samples used to assess the performance of these test methods. The specificity value determined for the MicroFoss system was 92.7%. The majority of microbes causing false positive results in the MicroFoss system were Bacillus species, which were readily distinguishable from Listeria species by a simple Gram stain and morphological features. Listeria monocytogenes (89.4%—MicroFoss, 88.0%—Culture) and Listeria innocua (8.8%—MicroFoss, 7.7%—Culture) were the most common isolates of Listeria detected by the two test methods, with L. monocytogenes being the most predominant isolate detected. The highly comparable results and rapid nature of the MicroFoss system demonstrate its effectiveness as a detection system for species of Listeria in environmental samples. The fact that the sensitivity of the MicroFoss system was similar to that of the culture method and the Listeria results were obtained within 48 h of testing, support the use of the MicroFoss as an alternative rapid method for screening large numbers of environmental samples for Listeria spp.

Purification of Escherichia coli-expressed HIS-tagged Maedi-Visna p25 core antigen by Ni2+-chelate affinity chromatography

In this study, recombinant histidine tagged p25 capsid protein of Maedi-Visna virus was developed. Part of the viral genome coding p25 protein was positioned downstream and in frame with a metal binding domain in pRSET-B vector. Recombinant protein was expressed in E. coli cells and soluble fraction of the protein was subsequently purified by Ni2+-chelate affinity chromatography. Purified protein was then used as antigen in an indirect ELISA test. One hundred fifty ovine serum samples were screened for antibodies to p25 protein of the virus. Immunoblot with whole virus antigen was used as a gold standard. The total number of positive results in the ELISA was 38 (25.33%). Immunoblot failed to confirm a positive result in 2 (1.33%) of them and these results were therefore considered to be false positive. The number of true positive results in the ELISA was thus 36 (24%). All immunoblot positive samples were also positive by ELISA test. In conclusion, recombinant His-tagged capsid protein showed very high sensitivity and specificity in detecting antibodies to Maedi-Visna virus.

Epidemiology of respiratory syncytial virus infection among infants over three winter seasons

A study involving respiratory syncytial virus was carried out on infants and young children hospitalised with acute respiratory tract infection over the period December 1987 to March 1990. During peak periods of RS virus activity 420 naso-pharyngeal aspirates were submitted to the Virus Reference Laboratory, Department of Medical Microbiology, U.C.D., mostly from the Dublin region. Using immunofluorescence, enzyme linked immunosorbent assay and cell culture techniques 206 samples (49%) were identified as positive for RS virus. Over the period of study RS virus seasonal activity was confined to the winter months October to March with peaks of activity occurring during March 1988, December 1988 and January 1990. Bronchiolitis was the most common clinical manifestation of infection accounting for 48% of the total number of positive results. Eighty two point five per cent of positive detections were reported from infants less than or equal to 6 months old and particularly from infants in the 1-2 month old age group. More males than females were found to be affected by RS virus infection.

Comparative results with five cannabinoid immunoassay systems at the screening threshold of 100 micrograms/L.

Five commercially available immunoassay techniques were compared for the detection of cannabinoid metabolites in urine at a positive cutoff of 100 micrograms/L. Numerical values, available for four of these techniques, were used to evaluate inter-assay equivalence at this threshold. The total number of positive results differed for each assay, with some individual samples exhibiting wide variations in numerical values. As a group, the radioimmunoassay systems gave a greater proportion of positive specimens than did enzyme-linked or fluorescence-polarization-based techniques. The single threshold of detection suggested by federal guidelines does not provide for equivalent screening of cannabinoids with these immunoassay techniques.

Contact dermatitis in patients with leg ulcers. The prevalence of late positive reactions and evidence against systemic ampliative allergy.

100 patients with leg ulcers were patch tested against a standard battery of allergens. The readings were carried out daily from the 2nd to the 7th days. 55 patients showed positive reactions to one or more allergens. 32% of positive reactions developed for the first time after 48 h and 11% after 72 h. No single day or combination of two days gave 100% positive results. A single reading on the 4th day gave the highest number of positive reactions at 92%. The prevalence of positive patch tests was significantly higher in patients with surrounding eczema, and in patients with positive patch tests the ulcer duration was significantly longer than in those with negative patch tests. The total number of positive results in individuals increased linearly with the duration of the ulcer. Of allergens to which the ulcer was exposed, the occurrence of multiple sensitivity was significantly greater than predicted from the prevalence of individual sensitivities. However, there was no association between medicaments and metal sensitivity. This, together with the absence of an exponential rise in the number of allergens with the duration of ulcer, does not support the theory of systemic ampliative allergy.

The use of liquid Löwenstein-Jensen medium in the primary isolation of tubercle bacilli

A technique for culturing tubercle bacilli in a liquid modification of Löwenstein medium is described. The liquid medium can be poured into the centrifuge tube on to the neutralized and washed sediment of the pathological material after it has been treated in the usual manner. After about 14 days incubation a smear of the liquid culture is made and examined microscopically with a magnification of about 120. If micro-colonies are observed, it is possible to carry out a drug sensitivity test by using this liquid culture as the inoculum. After the smear has been made a sub-culture of the liquid medium on to solid medium is carried out.Microscopical examination of the liquid cultures after two weeks incubation gives about two-thirds to nine-tenths of the total number of positive results which solid medium cultures give after three to eight weeks from the same specimens. Sub-culturing the liquid cultures on to solid medium after two weeks increases the number of positive findings and brings it equal to or greater than the number found by the use of primary solid medium culture. The combined use of primary liquid and solid culture increases the proportion of positive results by snore than one-fifth above that found by primary solid culture only.These methods have been successfully used in routine bacteriological work in the Tuberculosis Institute in Belgrade for culturing more than 250,000 specimens.

Tests of Hypotheses Concerning Matched Samples

McNEMAR (1947) considered the problem of testing the significance of the difference between two correlated sample proportions or frequencies, and Cochran (1950) presented one generalization of the problem in which there are c (> 2) matched or correlated samples. For example, specimens from each of a series of n patients may be subjected to a number of clinical tests for results concerning positive or negative findings. There is then the question about the possible significance amongst some or all of the clinical tests as regards the total number of positive results. In this paper it is shown that these are equivalent to problems of tests of linear hypotheses for multinomial and binomial variates. Appropriate chi-square tests and their limiting power functions are derived. An example using Maxwell's data (1961) is given which illustrates the case: c = 3. 2. MCNEMAR'S TEST (c = 2) Suppose then that there are only two observers or clinical test readings, the outcomes of which are represented by n pairs of l's or O's, respectively. The results may1ibe represented in the array given in Table 1.

Efficacy of different selective media for the isolation of salmonellae from faeces.

Comparative results obtained in isolating salmonellae from faeces by the use of tetrathionate broth, MS, and MM enrichment medium are given. The best results were obtained by tetrathionate broth prepared from infusion broth. The MS as well as the MM medium increased the total number of positive results.