PhD defence A.C. (Anna) Randag

Below is a brief summary of the dissertation: 

This thesis focuses on trends, risk factors, outcomes and preventability of microbial keratitis. Microbial keratitis, caused by bacterial, fungal or protozoal infection and aggravated by inflammation, can lead to severe visual loss. Chapter 2 presents a nationwide Dutch survey (2009–2015) identifying 224 cases of Acanthamoeba keratitis, related to contact lens wear in 95% of cases. We observed an increased incidence over the study period. Treatment failure, defined as a best-corrected visual acuity of less than 0.5 Snellen decimals or the need for keratoplasty, occurred in 39% of cases. Advanced age, higher disease severity at diagnosis, prior corticosteroid use and tertiary referral were major risk factors. Chapter 3 describes a case-control and clinical-epidemiological study (2009–2020) on Acanthamoeba and Fusarium keratitis, revealing preventable risks such as exposure to surface water, poor lens hygiene, smoking and sleeping with lenses. Chapter 4 shows that most commercial contact lens solutions available in the Netherlands were ineffective against Acanthamoeba trophozoites and cysts, stressing the need for strict hygiene and improved testing standards. Chapter 5 reports a rise in adult gonococcal keratoconjunctivitis cases in Western Europe (2017–2023), highlighting the need for surveillance and treatment standardisation. Chapter 6 notes a decline in MK during the COVID-19 pandemic, possibly due to improved hygiene. In Chapter 7 we integrated these findings, emphasising awareness, prevention and early diagnosis to reduce MK-related vision loss.