Bacterial etiology and antimicrobial resistance trends in ocular infections: A 30-year study, Turin area, Italy

Abstract

Purpose: Bacterial ocular infections can result in loss of all or part of the ocular structures, contributing to a high disability charge. Local surveillance of etiology and susceptibility patterns is crucial for an appropriate empiric management of ocular infections. The aim of this study was to analyze of bacterial spectrum in culture-proven ocular infections and trends of antimicrobial susceptibility patterns. Methods: A monocentric retrospective study was performed including ocular infection cases diagnosed at the Microbiology Unit of Turin Ophthalmic Hospital between 1988 and 2017. Spectrum of pathogens that caused bacterial culture-proven ocular infections and trends of antimicrobial susceptibility patterns were analyzed. Results: A total of 15,517 culture-positive isolates were identified as causative agents of ocular infections. Gram-positive bacteria were deemed to cause infection in 73.5% of cases. Staphylococcus spp. and Pseudomonas spp., coagulase-negative staphylococci, Staphylococcus aureus were the leading causative pathogens of keratitis, endophthalmitis, and conjunctivitis, respectively. Statistically significant changes in temporal trends were observed for all analyzed microorganism groups except for Enterobacteriaceae group. Overall, fluoroquinolones and chloramphenicol demonstrated to be the most effective antimicrobials in vitro toward bacterial ocular infections, followed by tetracycline, ampicillin, and aminoglycosides. Enterobacteriaceae isolates showed higher multi-drug resistance rate, followed by coagulase-negative staphylococci. Analysis of resistance rates over time highlighted increasing resistance trend for aminoglycosides among Gram-negative and for both aminoglycosides and fluoroquinolones among Gram-positive pathogens, especially for S. aureus. Conclusion: This study provided a 30-year assessment of bacterial ocular infections in an urban area of Italy, giving support to epidemiological consciousness and guiding empiric antimicrobial therapy.

Clinical Characteristics of External Ocular and Periocular Infections and Their Antimicrobial Treatment Patterns Among a Ghanaian Ophthalmic Population; A Multicenter Study

“…For example, among the various ocular microbiology investigations conducted across Ethiopia, by Ayebubizu et al 5 , Belyhun et al 2 , Assefa et al 10 as well as Getahun and colleagues 8 the proportionate distribution of Gram-negatives were similar to Gram positives. Of note, whereas the magnitude of Gram-negative bacteria etiology found in Australia 21 , Iran 20 and Italy 24 were not equivalent to our ndings as well as studies in parts of Ethiopia, the proportion estimates reported were relatively higher. There exist regional variations in the patterns of distribution of Gram-negative bacteria, however, the higher prevalence in our study are ascribed to hygiene as the primary mode of transmission of these enteric bacteria are through oral-fecal contamination.…”

“…Globally, eye infections of bacteria origin remain a signi cant contributor to ocular morbidity and blindness, and the burden is increasing 1,2 . Further, results from ocular microbial studies across different populations show no obvious pattern in prevalence estimates (ranging from 21.8-82.5%) across Africa [2][3][4][5][6][7][8][9][10][11][12] , Asia [13][14][15][16][17][18][19][20] , Australia 21,22 , Europe [23][24][25] and North America 26 . Similarly, the bacterial etiology speci cally proportion and nature of Gram bacteria as well as the species of bacteria commonly implicated in ocular and periocular infections vary across geographical regions and settings 2-13,15−20,22,24−26 .…”

Prevalence and Antibiotic Resistance Patterns of Ocular Bacterial Strains Isolated from Pediatric Patients in University Hospital of Campania “Luigi Vanvitelli,” Naples, Italy

“…e most common bacterial pathogens, involved in pediatric ocular infection are coagulase-negative Staphylococci (CoNS), Staphylococcus aureus (S. aureus), Streptococcus pneumoniae, Pseudomonas aeruginosa (P. aeruginosa), and Haemophilus influenzae [11]. Gram-positive bacteria are primarily responsible for pediatric ocular infection [12]. A prospective study conducted in the United States has revealed that 65% of children have ocular infections caused by Gram-positive bacteria [13].…”

Antimicrobial resistance of ocular microbes and the role of antimicrobial peptides

“…124 A similar study from Italy, with a 30-year follow up , reported an increasing rate of resistance of S. aureus to antibiotics, from 21 per cent in 2003 to 38 per cent in 2015, as well as for S. pneumoniae (7.4 per cent to 23.3 per cent). 125 In the same study, multidrug (resistant to at least one aminoglycoside and one fluoroquinolone) resistance rates of S. aureus were significantly increased from 8.7 per cent to 12 per cent, as was resistance in isolates of Enterobacteriaceae (24.5 per cent to 34.6 per cent). 125 Retrospective studies have reported increasing rates of MRSA.…”

“…125 In the same study, multidrug (resistant to at least one aminoglycoside and one fluoroquinolone) resistance rates of S. aureus were significantly increased from 8.7 per cent to 12 per cent, as was resistance in isolates of Enterobacteriaceae (24.5 per cent to 34.6 per cent). 125 Retrospective studies have reported increasing rates of MRSA. 69,126 An increasing prevalence of ocular MRSA infections from nine per cent to 38 per cent over a 10-year period (2007-2017) of study duration has been reported.…”