Abstract
Purpose: :
To review characteristics on confocal microscopy, clinical presentation, and clinical outcome in 266 cases of Acanthamoeba keratitis (AK) over a ten year period.
Methods: :
A retrospective case review was performed on 266 cases of AK diagnosed by confocal microscopy at a single institution from 1999-2008.
Results: :
Confocal microscope case logs and medical records were reviewed for 266 subjects referred for confocal microscopy and definitive diagnosis of AK. A single clinician performed and interpreted the confocal microscopic evaluation in each case, and a numbered grading system was devised for describing the relative microscopic severity (grade 1 = least severe, grade 4 = most severe). Of the 266 cases, 143 were described as "grade 1," 69 as "grade 2", and 54 as "grade 3" or higher. Medical records were available for review in 180 of the 266 cases. Sixty-two of these cases presented with Snellen acuity of 20/25 or better in the worse-seeing eye, 89 cases presented with 20/30 to 20/100 acuity, and 29 cases presented with 20/125 or worse acuity. Thirty cases had a definite history of Herpes simplex (HSV) infection (prior or conconcurrent). One hundred-eight of the 180 records indicated a history of soft contact lens use. Twenty-seven cases were culture-positive for AK, 80 were culture-negative, and 73 had unknown culture results. Many cases were lost to follow-up after the microscopic diagnosis was made, usually as referring providers resumed management. One hundred seventeen cases were followed through microscopic resolution of AK or another clinical endpoint. Seventy-nine of these demonstrated 20/25 acuity or better at the time of AK resolution, 24 demonstrated 20/30 to 20/100 acuity, and 9 cases demonstrated 20/200 or worse. Seven of these progressed to multiple failed penetrating keratoplasty (PKP) and/or enucleation.
Keywords: Acanthamoeba • keratitis • clinical (human) or epidemiologic studies: outcomes/complications