Prevalence and antibiotic susceptibility of bacteria isolated in patients affected with blepharitis in a tertiary eye centre in Spain

Abstract

Purpose: To describe which bacteria can be found on lid margins in patients affected with blepharitis, to show their antibiotic susceptibility pattern, and to evaluate the antibiotic resistance trend of coagulase-negative Staphylococcus through time. Materials and methods: Consecutive cases of 198 eyes affected with blepharitis between 2012 and 2018 were reviewed. A sample was collected by rubbing a swab against the base of the eyelashes of both the eyes of all patients. The samples were inoculated in blood agar and chocolate agar. The susceptibility of the identified bacteria to common antibiotics was tested. In addition, the antibiotic susceptibility pattern of coagulase-negative Staphylococcus detected from year 2016 to 2018 was compared with that of 4 years before. Results: The most common isolated bacterium was coagulase-negative Staphylococcus (89%) and Staphylococcus aureus (28%). Coagulase-negative Staphylococcus showed highest susceptibility to vancomycin (100%), neomycin (94%) and chloramphenicol (91%). Coagulase-negative Staphylococcus and Staphylococcus aureus were the most resistant to penicillin and erythromycin (resistance in 92%, 91% for coagulase-negative Staphylococcus, 86% and 43% of eyes for Staphylococcus aureus). Corynebacterium was resistant to oxacillin and erythromycin. Streptococcus viridans showed resistance to gentamycin and tobramycin. Moraxella was susceptible to most antibiotics. Bacillus was resistant to oxacillin. The antibiotic resistance trend of coagulase-negative Staphylococcus showed that the resistance to rifampicin increased through the years 2012–2018. Conclusion: Coagulase-negative Staphylococcus and Staphylococcus aureus were the most isolated bacteria in patients affected by blepharitis in our tertiary eye centre. Both bacteria were resistant to erythromycin. Through the years, it seems that coagulase-negative Staphylococcus gained resistance to penicillin, erythromycin, ciprofloxacin and rifampicin.

Composition and Diversity of the Ocular Surface Microbiota in Patients With Blepharitis in Northwestern China

“…Bezza et al reported that the abundance of Propionibacterium acnes was almost the same in the blepharitis group and the normal control group ( 9 ). The differences between these studies were considered to be related to differences in environmental and culture conditions ( 6 , 11 , 12 ).…”

“…In past decades, several studies have investigated the ocular surface microbiota of blepharitis using culture approaches and found that Staphylococcus epidermidis, Staphylococcus aureus, Corynebacterium macginleyi , and Propionibacterium acnes were the most common species that appeared in cultures of eyelid margin or conjunctival sac samples from either patients with blepharitis or healthy controls ( 7 – 10 ). The relative differences in the prevalence of each bacterium were remarkable among the study groups from different parts of the world, which was believed to be due to the effects of different climates and environments ( 6 , 11 , 12 ). However, it is still doubtful whether the results of culture, which is susceptible to the influence of culture conditions, can reflect the true composition of the microbiota.…”

Metagenomic profiling of ocular surface microbiome changes in Demodex blepharitis patients

“…The relative abundance (RA) of each member of the microbiome and interactions among microbial species are crucial for the homeostasis and sustainability of ecosystems (Wintermute and Silver, 2010;Kumar et al, 2016). Disruption of the stable state can lead to ocular surface diseases, such as dry eye, meibomian gland dysfunction (MGD), and blepharitis (Zhu et al, 2018;de Paula et al, 2019;Yan et al, 2020).…”

Bacterial isolates and antimicrobial susceptibility pattern of ocular infection at a tertiary referral hospital in the South of Italy

“…These are assumed to be commensal bacteria, colonizing the mucosa and lid margins. Along with Staphylococcus aureus, CoNS are the most commonly isolated bacteria in patients affected by blefaritis, 14 keratitis, 15 and conjunctivitis. 16,17…”

“…These are assumed to be commensal bacteria, colonizing the mucosa and lid margins. Along with Staphylococcus aureus, CoNS are the most commonly isolated bacteria in patients affected by blefaritis, 14 keratitis, 15 and conjunctivitis. 16,17 In our study, among the 183 isolates, predominant bacteria were Gram positive bacteria, in particular Staphylococcus species, out of which only 3,6% were Staphylococcus Aureus and 96,4% were CoNS, a percentage respectively much lower and much higher as compared to a report in northern Ethiopia.…”