Maryam Rad,1Gholamhossein Ebrahimipour,2Mojgan Bandehpour,3,*Omid Akhavan,4Fatemeh Yarian,5
1. Department of Microbiology and Microbial Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran 2. Department of Microbiology and Microbial Biotechnology, Faculty of Life Sciences and Biotechnology, Shahid Beheshti University, Tehran, Iran 3. Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran-Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran 4. Department of Physics, Sharif University of Technology, Tehran, Iran 5. Cellular and Molecular Biology Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran-Department of Medical Biotechnology, School of Advanced Technologies in Medicine, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Introduction: Neisseria meningitidis is one of the main causes of the spread of meningitis in the world, which is a gram-negative bacterium that the only host of this bacterium is humans[1].
Of the 13 serogroups (A, B, C, D, E, H, I, K, L, W, X, Y, and Z) of this bacterium that are classified based on polysaccharide capsules, five serogroups ( A, B, C, Y, W-135) are the cause of most diseases in humans, with serogroups A and C being the most common cause of meningococcal meningitis. But severe epidemics caused by B, Y and W-135 groups have also been seen. Despite the declining prevalence of meningitis due to vaccination, bacterial meningitis is still a public health problem, with about 200,000 people dying from bacterial meningitis worldwide each year, with up to 60% of deaths reported in sub-Saharan Africa and developing countries. If treated, this rate is reduced to 10%, but most serious complications such as amputation, nerve defects and other serious disabilities have been observed in the survivors.
The main methods of diagnosis of Neisseria meningitidis in most parts of the world are PCR, ELISA and culture, which is a authentic standard PCR [2].
Standard reference methods have the following problem:
• Requires an experienced technician and equipped laboratory
Among the limitations of cultivation, we can mention such things as:
• The possibility of sample contamination during storage or improper transfer
• Effects of initial antibiotic treatment [3]
People of all ages are at risk for life-threatening meningococcal meningitidis. Because the disease can cause permanent damage to the central nervous system or cause death within a few hours, it is important to know the disease quickly [4].
Rapid diagnostic tests:
According to the International Organization for Standardization (ISO), the point-of-care test (POCT) is defined as a test that allows a change in a person's care to be made by allowing the patient to be examined on or near the patient's site. One type of care point test is a rapid diagnostic test (RDT). Rapid diagnostic tests qualitatively or semi-quantitatively identify antigen or antibody in a patient sample [5].
Rapid diagnostic tests can detect Neisseria meningitidis in a cerebrospinal fluid (CSF) specimen without the need for initial preparation (centrifugation or heating). Detection of antigen in CSF sample by antibody coated on the surface of gold nanoparticles and nitrocellulose membrane, ie immunochromatography, is the basis of the performance of these tests. These tests have advantages such as cost-effectiveness, mass production, and stability in hot weather for weeks. The basis of the work is that the test is immersed in the tube containing the sample and after a period of time about 10 to 15 minutes, the result is checked. The color change indicates that the test is positive [6]. Figure 1 shows a schematic of a rapid diagnostic test based on immunochromatography [7].
Methods: After searching in databases such as Google Scholar, Pub Med and Science Direct, related articles were selected and used.
Results: Because effective treatment of meningitis requires identifying the pattern of antibiotic susceptibility of the bacterium, as well as common diagnostic methods such as culture, it is time consuming and the bacterium may not grow [10], so rapid diagnostic tests are important. These tests can also be used as a supplement. For example, in addition to clinical picture and CSF examination, you can use rapid diagnostic tests, the positive results of which indicate a possible infection with the bacterium Neisseria meningitides [6].
Conclusion: Despite the development of rapid diagnostic tests in recent years, these tests still need to be optimized. Due to the problems mentioned in Table 1 and on the other hand the importance of rapid diagnosis of meningitis, we need tests that can be sufficiently effective and on the other hand the problems mentioned in their design have been minimized.