Diagnostic accuracy of gold nanoparticle combined with molecular method for detection of Mycobacterium tuberculosis: A systematic review and meta-analysis study

The importance of rapid detection of Mycobacterium tuberculosis (MTB) has become greater than ever. Among biosensors as a rapid test, gold nanoparticles (GNPs) can play an important role in accelerating the diagnosis of TB. This systematic review and meta-analysis study were conducted to evaluate the diagnostic accuracy of GNPs for the diagnosis of MTB. All cross sectional and case control studies as original article about rapid detection of MTB using GNPs combined with molecular methods published in PubMed, Web of Science, and Scopus databases were selected, retrieved and appraised up to September 2021. The sensitivity and specificity of GNPs in different studies ranges from 83.7% to 100% for sensitivity and from 86.6% to 100% for specificity. The highest sensitivity and specificity of GNPs combined with molecular methods was related to the LAMP method. Therefore, GNPs are a simpler, low cost and more efficient way in the clinical diagnosis of TB

Prevalence of Mycobacterium tuberculosis mutations associated with isoniazid and rifampicin resistance: A systematic review and meta-analysis

Tuberculosis (TB) is still one of the leading causes of worldwide death, especially following the emergence of strains resistant to isoniazid (INH) and rifampicin (RIF). This study aimed to systematically review published articles focusing on the prevalence of INH and/or RIF resistance-associated mutations of Mycobacterium tuberculosis isolates in recent years. Literature databases were searched using appropriate keywords. The data of the included studies were extracted and used for a random-effects model meta-analysis. Of the initial 1442 studies, 29 were finally eligible to be included in the review.The overall resistance to INH and RIF was about 17.2% and 7.3%, respectively. There was no difference between the frequency of INH and RIF resistance using different phenotypic or genotypic methods. The INH and/or RIF resistance was higher in Asia. The S315T mutation in KatG (23.7 %), C-15 T in InhA (10.7 %), and S531L in RpoB (13.5 %) were the most prevalent mutations. Altogether, the results showed that due to S531L in RpoB, S315T in KatG, and C-15 T in InhA mutations INH- and RIF-resistant M. tuberculosis isolates were widely distributed. Thus, it would be diagnostically and epidemiologically beneficial to track these gene mutations among resistant isolates

A gold nanoparticle colorimetric probe-based biosensor for rapid detection of VIM-2 and IMP-1 metallo-beta lactamase genes

Despite actions to reduce the prevalence of antibiotic resistance, antibiotic resistance remains a major threat in the treatment and control of infections. Therefore, the development of rapid diagnostic methods plays a significant role in the detection of antibiotic resistance genes and the management of hospital infections. This study aimed to design and develop a gold nanoparticle colorimetric probe-based biosensor was developed for faster and more accurate detection of VIM-2 and IMP-1 Metallo-Beta-Lactamases (MBLs) genes in different clinical samples. After identifying 248 clinical isolates of bacteria with standard biochemical methods and evaluation of antibiotic resistance and identifying MBL-producing strains, PCR method was carried out for detecting VIM-2 and IMP-1 genes as a gold standard. Synthesis of AuNPs were done by citrate reduction method and AuNP -IMP-1 biosensor was used for detecting IMP-1 gene, after functionalization of thiol modified oligonucleotides. AuNP biosensor and IMP-1 PCR were compared in terms of detection indices. Method PCR was defined as the gold standard. Bacteria examined, 87 isolates were resistant to carbapenems. Out of the 87 carbapenem-resistant isolates, 85 (34.2%) were phenotypically positive for MBLs. Also, 7 isolates had IMP-1 gene, but none of them carried VIM-2 gene. The AuNP biosensor had 100% sensitivity, specificity, PPV and NPV, respectively. The final detection limit of IMP-1 genomic DNA (LOD) by PCR and AuNP-IMP-1 biosensor technique was 0.1 fg/μl (2.5 fg/25 reactions) and 0.001 fg/μl (0.025 fg/25 reaction), respectively. According to the promising results of Diagnostic indices, AuNP biosensor is a more efficient and accurate method for direct and indirect detection of antibiotic resistance genes in clinical samples

Additional file 1 of Global prevalence of Clostridioides difficile in 17,148 food samples from 2009 to 2019: a systematic review and meta-analysis

Additional file 1. The ribotypes of the studies