Antimicrobial susceptibility pattern of oral isolates of Aggregatibacter actinomycetemcomitans

Abstract

Background: Aggregatibacter actinomycetemcomitans is involved in the etiology of localized aggressive periodontitis (LAP), a condition that frequently requires supplemental antibiotic therapy. Information on antimicrobial susceptibility pattern and guidelines for oral antibiotic therapy are not available on Indian patients. Aim: The main aim of the present study was to screen clinical isolates on a panel of antibiotics commonly used for oral/systemic therapy. Materials and Methods: The study included 40 strains of A. actinomycetemcomitans isolated from patients with LAP. The subgingival plaque was plated onto Trypticase Soy Serum Bacitracin Vancomycin Agar medium and incubated for 72 h, and suspected colonies were confirmed by phenotypic tests. Each isolate was tested against a panel of 12 antibiotics using MIC gradient strip test. ATCC strains of A. actinomycetemcomitans serotype A and C were used as standards. Performance and interpretation of the test were done according to the manufacturers’ instructions. Distribution of MICs among isolates ( n = 40) were used to calculate concentrations inhibiting 50% (MIC 50 ) and 90% (MIC 90 ) of strains. Results: Moxifloxacin, cefotaxime and ceftriaxone showed excellent activity with 100% growth inhibition followed by amoxicillin, amoxiclav and doxycycline (>90% activity). The bacterial strains were moderately susceptible to cefuroxime, cefazolin and tetracycline but displayed poor susceptibility to clindamycin and azithromycin. All isolates were resistant to metronidazole. Conclusion: The isolates of A. actinomycetemcomitans displayed a high level of resistance to azithromycin and clindamycin. Development of resistance against tetracycline also appears to be significant. Variable resistance among the different members of the cephalosporin group is a factor to be investigated further since susceptibility profile against these antibiotics and interpretative criteria for oral bacteria are not available.

Antimicrobial resistance of microorganisms present in periodontal diseases: A systematic review and meta-analysis

“…Fifteen studies ( Gamboa et al, 2013 , 2014 ; Ehrmann et al, 2014 ; Xie et al, 2014 ; Collins et al, 2016 ; Bhardwaj et al, 2017 ; De-la-Torre et al, 2017 ; Arredondo et al, 2019 , 2020 ; Bhat et al, 2019 ; Mínguez et al, 2019 ; Almeida et al, 2020 ; Ardila and Bedoya-Garcia, 2020 ; Irshad et al, 2020 ; Aguilar-Luis et al, 2021 ) were conducted in a University/Dentistry College. Three studies were conducted in a public dental clinic ( Binta and Patel, 2016 ; Akrivopoulou et al, 2017 ; Ansiliero et al, 2021 ), and other three studies were conducted in private clinics ( Rams et al, 2011 , 2014b , 2020 ).…”

“…Three studies reported chronic periodontal infection ( Gamboa et al, 2014 ; Bhardwaj et al, 2017 ; De-la-Torre et al, 2017 ), two studies reported a diagnosis of aggressive infection ( Akrivopoulou et al, 2017 ), six studies reported a diagnosis of severe/moderate infections ( Rams et al, 2011 , 2014a , 2014b , 2020 ; Binta and Patel, 2016 ; Bhat et al, 2019 ), two studies reported more than one type of infection ( Collins et al, 2016 ; Arredondo et al, 2020 ), and 11 studies did not report the diagnosis of periodontal infection ( Gamboa et al, 2013 ; Ehrmann et al, 2014 ; Xie et al, 2014 ; Dhotre et al, 2015 ; Arredondo et al, 2019 ; Mínguez et al, 2019 ; Uribe-Garcia et al, 2019 ; Almeida et al, 2020 ; Irshad et al, 2020 ; Aguilar-Luis et al, 2021 ; Ansiliero et al, 2021 ).…”

Multiomic Analyses of Nascent Preterm Infant Microbiomes Differentiation Suggest Opportunities for Targeted Intervention

“…This suggests the need to consider treating upstream sources of milk [ 69,70 ] (the human milk donor, or screening of human milk for S. aureus ), which may mitigate the need for this vulnerable preterm population to directly receive antibiotic treatment that would disrupt microbiome development. In addition, the increased ratio of Aggregatibacter in formula‐supplemented infants, observed previously, [ 33 ] may indicate an early risk exposure for the later development of caries [ 71,72 ] as well as localized aggressive periodontitis [ 73–75 ] which may require treatment with antibiotics. Limiting antibiotics to a local application may ameliorate the global dysfunctional differentiation observed with systemic antibiotic exposure in our cohorts.…”

Porphyromonas Gingivalis: Biofilm Formation, Antimicrobial Susceptibility of Isolates From Cases of Localized Aggressive Periodontitis (Lap)

“…Almost all researchers have shown that moxifloxacin has excellent activity against oral microbes, 32,33-34,36 results similar to the results of the current study where the drug showed a high sensitivity of 100% (Table 2). Only a few studies discuss the activity of different cephalosporins on P. gingivalis strains 31, 32 . The current study found the results to be highly variable.…”