Results Of Antigen Detection Research Articles

A grid management system for COVID-19 antigen detection based on image recognition

ObjectiveTo develop a SARS-CoV-2 antigen detection management system for Chinese residents under community grid management, which is supported by “health information technology” and “neural network image recognition”, so as to give full play to the advantages of “grid management”. This system is applied to the normalized prevention and control of COVID-19 epidemic. MethodsThe model of image recognition algorithm was built based on deep learning and convolution neural network (CNN) artificial intelligence algorithm. The improved Canny edge detection algorithm was used to monitor and locate the image edge, and then the image segmentation and judgment value calculation were completed according to projection method. The system construction was completed combing with the grid number design. ResultsThe proposed method had been tested and showed the accuracy of the algorithm. With a certain robustness, the algorithm error was proved to be small. Based on the image recognition algorithm model, the development of SARS-CoV-2 antigen detection management system covering user login, paper-strip test image upload, paper-strip test management, grid management, grid warning and regional traffic management was completed. ConclusionsAntigen detection is an important supplementary means of COVID-19 epidemic prevention and control in the new stage. The SARS-CoV-2 antigen detection management system for Chinese residents under community grid managemen based on image recognition enables mobile communication devices to recognize the image of SARS-CoV-2 antigen detection results, which is helpful to form a grid management mode for the epidemic and improve the management framework of epidemic monitoring, detection, early warning and prevention and control.

Usefulness of rapid antigen detection for the diagnosis of systemic infections due to Haemophilus influenzae

Twenty-eight cases of systemic infections due to Haemophilus influenzae diagnosed from October 1988 to December 1998 were analyzed retrospectively. The clinical manifestations were 13 meningitis (15 episodes), 9 septic arthritis, 4 acute epiglottitis, 1 septicemia and 1 lung abscess. In the 15 meningitis episodes, 13 had positive CSF culture results, and the other 2 episodes of pretreated with antibiotics were diagnosed by H. influenzae type b (Hib) antigen detection by using concentrated urine specimens. In the 9 septic arthritis cases, 6 had positive synovial fluid culture results. Of the 3 cases with negative results on Gram stain and on synovial fluid and blood cultures, etiological diagnosis was established by Hib antigen detection in synovial fluid. Results of Hib antigen detection were positive in all 8 cases (100%). In 6 of these 8 cases, antimicrobial therapy was started by the results of antigen detection. In the 4 acute epiglottitis, 2 had positive blood culture results, and the other 1 case was diagnosed by Hib antigen detection by using concentrated urine specimen. In 3 of these 4 cases, H. influenzae strains isolated from nasopharyngeal swab or aspirated sputum were serotyped as type b. In this study, rapid antigen detection has several advantages in the rapid laboratory diagnosis of systemic infections due to Haemophilus influenzae. 1. The detection of Hib antigen is the only way to diagnose bacterial etiology of infection in patients who had received partially treatment with antimicrobials. Urine is as an appropriate specimen for antigen testing as CSF in patients with suspected Hib meningitis. Moreover, to detect Hib antigen in synovial fluid is clinically useful in septic arthritis. 2. Both the antigen detection and Gram stain made the rapid presumptive identifications and effected therapeutic decision making. 3. Antigen detection methods have also been used in serotyping of clinical isolates. We conclude that rapid antigen detection is a very useful tool for the rapid etiological diagnosis and guideline for the choice of antimicrobials in systemic infections due to Hib. It is necessary to diagnose bacterial etiology as a routine procedure using not only Gram stain and culture but also rapid antigen detection technique in patients with suspected Hib systemic infection.

Evaluation of single whole inclusion serum test for IgG antibody to Chlamydia trachomatis in asymptomatic women.

IgG antibody titres against Chlamydia trachomatis were measured using a whole inclusion assay (Electro-Nucleonics Laboratories, Bethesda, Maryland, USA) in single serum samples of patients who presented for termination of pregnancy with evidence of infection with this organism (case group) and of 30 women with no evidence of infection (control group). Case and control patients were matched for age, race, marital status, history of sexually transmitted diseases, number of lifetime sexual partners, and whether they had had a new sexual partner in the preceding month. Fifty eight of 60 (97%) serum samples tested had chlamydial antibodies present at a titre of 1/8 or more. There was no significant difference between the geometric mean titres of the 30 case patients and the 28 controls with chlamydial antibodies (1/161.3 and 1/77.4 respectively). Significantly more case patients than controls, however, had a titre of 1/128 or more (p less than 0.01). The sensitivity, specificity, and positive and negative predictive values of a single serum antibody titre of 1/128 or more as an indicator of recent infection compared with isolation of the organism in cycloheximide treated McCoy cells or antigen detection by Chlamydiazyme (Abbot Laboratories; North Chicago, Illinois, USA), or both, were each 67%. The value of the antibody assay seems to be questionable as high levels of antibodies failed to correlate with isolation or antigen detection results, or both, in our population.