RT Journal Article
A1 Johnson, Zoe K
A1 Narayanan, Manjusha
A1 Siah, We Fong
A1 Anwar, Hamed
A1 Figueiredo, Francisco C
T1 An analysis of the incidence, management, clinical outcomes and risk factors of Acanthamoeba keratitis infections in a tertiary hospital in the UK over the last 5 years
JF Investigative Ophthalmology & Visual Science
JO Invest. Ophthalmol. Vis. Sci.
YR 2015
VO 56
IS 7 
SP 1889
OP 1889
SN 1552-5783
AB  Acanthamoeba keratitis (AK) is typically characterized by a rapidly progressive course with increasing pain and deterioration of vision as the disease progresses. The aim of this study is to report the incidence of AK at the Royal Victoria Infirmary (RVI), Newcastle-upon-Tyne, between 2011 to 2014 and analyze the factors associated with both good and poor visual outcomes. A retrospective case note review was performed of all microbiology confirmed consecutive patients who underwent corneal scrapes specifically for acanthamoeba keratitis at the RVI, between November, 2011 to November, 2014. Cases that were lost to follow-up or moving out of the area were excluded from the study. Fourteen cases of AK were identified, i.e. mean age 32; range 21-76; M=8 F=6). The mean time to diagnosis from symptom onset to first presentation to an ophthalmologist was 15 days (range 1-21 days). The mean time from first ophthalmic examination to securing a diagnosis of AK was 25 days (range 0-124 days), with an average of 3 physician visits (range 1-9) needed before a diagnosis of AK was suspected clinically. Fifty seven percent of patients were initially treated as herpetic keratitis prior to diagnosis. Two patients received topical steroids prior to diagnosis, which led to considerable worsening of their condition. In all cases, corneal scraping and culture confirmed the diagnosis. Cysts were seen on in vivo confocal microscopy in 4 cases. The mean duration of topical treatment was 7.5 months. A reactivation of AK occurred in 1 case. There were 4 cases where an early diagnosis of AK was established, all of whom had best corrected visual acuity of 20/30 or better at last follow-up. Corneal scarring necessitating penetrating keratoplasty (PKP) occurred in 4 patients, while cataract and glaucoma due to AK occurred in 2 patients. A moderate increase in the incidence of AK was noted (2014 - 5 cases, 2012 - 2 cases). Seventy nine percent of all subjects used soft monthly contact lenses. In all cases, corneal scraping and acanthamoeba culture primarily made a diagnosis of AK. Better visual outcomes were associated with earlier diagnosis, while cases with poorer visual outcomes were diagnosed later. Steroid administration prior to diagnosis of AK was associated with a poorer prognosis. 
RD 3/7/2021