Intracameral vancomycin following cataract surgery: An eleven-year study

Deepa R Anijeet, Prasad Palimar, Clive O PeckarDepartment of Ophthalmology, Warrington and Halton NHS Trust, UKAim: To compare the incidences of endophthalmitis after cataract operations before and after introduction of intracameral vancomycin at the end of surgery.Methods: A retrospective analysis was performed of presumed infectious endophthalmitis after cataract surgery from January 1, 1998 to December 31, 2008. From January 2001, the practice of using intracameral vancomycin at the end of cataract surgery was introduced. The period before introduction of intracameral vancomycin is considered as period A and that after as period B. The incidences of presumed or culture-proven endophthalmitis during periods A and B were compared.Results: A total of 16,606 cataract surgeries were performed during the study period. The incidence of endophthalmitis per 1000 cataract surgeries was 3.0 during period A and 0.08 during period B. This reduction was statistically significantly (Chi-squared test 36.6, P value < 0.0001). The relative risk of developing endophthalmitis without intracameral vancomycin prophylaxis was 38. The absolute risk reduction was 292 cases of endophthalmitis per 100,000 cataract surgeries.Conclusions: Intracameral vancomycin significantly reduced the incidence of postoperative endophthalmitis after cataract surgery. There is a universal need to adopt this mode of microbial prophylaxis to reduce the burden of endophthalmitis after cataract surgery.Keywords: endophthalmitis, intracameral vancomycin, cataract surger

Acanthamoeba keratitis: Molecular typing of Acanthamoeba species directly from ocular tissue

This report explores the molecular profiling of Acanthamoeba spp. from individuals in the UK suffering from a debilitating, sight-threatening disease of the cornea known as Acanthamoeba keratitis (AK). Seventy ocular samples from individuals undergoing investigations for AK were sent to the Scottish Microbiology Reference Laboratories (SMiRL), Glasgow during 2017–2019, and subjected to DNA extraction followed by in-depth molecular typing using a nested PCR/bi-directional sequencing approach. Of the 70 samples tested, 40 were PCR-positive. Of these, 32 were successfully sequenced and assigned to two of 23 existing genotypes termed T1 to T23. Molecular profiling of the 32 samples highlighted two genotypes, namely T3 (n = 3) and T4 (n = 29). For those 29 samples identified as the T4 genotype, a sub-genotype (T4A-T4H) was recorded: T4A (n = 18); T4B (n = 5); T4C (n = 1); T4E (n = 4); and T4F (n = 1). This study highlights that the T4 genotype and T4A subtype are the predominant molecular variants to cause ocular disease in the UK. Gaining in-depth information on the molecular profiling of Acanthamoeba spp. is essential to increase our understanding of the source(s) of infection, transmission pathways, and potential associations with clinical outcomes for this rare, yet potentially debilitating ocular disease