Epidemiology of bacterial corneal ulcers at tertiary centres in Vancouver, B.C.

Characterization of baseline polybacterial versus monobacterial infections in three randomized controlled bacterial conjunctivitis trials and microbial outcomes with besifloxacin ophthalmic suspension 0.6%

“…Consistent with other studies [10,18], few polybacterial infections featured combinations of Gram-negative bacteria only. Significant differences were found between poly-and monobacterial conjunctivitis infections with respect to the prevalence of specific infecting bacteria.…”

“…For instance, studies of polymicrobial infections have documented alterations in virulence factors, biofilm formation, and antibiotic resistance or tolerance [5]. While much research has focused on the pathogenesis of the polymicrobial nature of systemic infections, research on polymicrobial infections of the eye has been limited to studies reporting on the frequency of such infections in keratitis and/or endophthalmitis, with rates ranging from 2-50% [10,11,14,[15][16][17][18][19][20][21][22][23], or as high as 83% for endophthalmitis using polymerase chain reaction amplification techniques [24].…”

Infectious Keratitis: The Great Enemy

“…The keratitis usually occurs after a break in the corneal epithelium [45,68]. The major risk factors are contact lens wear, corneal abrasions, and ocular trauma [43,45].…”

“…Contact lens wear and lagophthalmos were identified as the major risk factors for the development of Gram-negative infection [18,66]. Preexisting ocular disease and previous HSV keratitis were associated with Gram-positive infectious keratitis [18,68].…”

“…Topical fluoroquinolones usually prescribed as first-line empiric initial treatment of suspected bacterial keratitis are at least as effective as combined fortified antibiotics [69]. Even though the susceptibility of Gram-negative bacteria to fluoroquinolone monotherapy was high, the susceptibility of Gram-positive bacteria was less and more variable [11,68]. Because of shift in antibiotics resistance patterns, in some regions, fluoroquinolone monotherapy is not recommended for severe infectious keratitis, but combined fortified antibiotics should be prescribed instead [11].…”