Overnight orthokeratology-associated microbial keratitis.
OBJECTIVE
This study was designed to report the clinical aspects, microbiologic findings, and treatment outcomes of overnight orthokeratology-associated microbial keratitis.


METHODS
Medical records of patients with overnight orthokeratology-associated microbial keratitis at National Taiwan University Hospital from August 2000 to October 2001were reviewed. The clinical and microbiologic characteristics and treatment outcomes were investigated.


RESULTS
Nine patients (in total 10 eyes) from aged 8 to 17 (mean, 12.3 +/- 2.9) years were included in this study. Eight patients had a unilateral infection and one had a bilateral infection. The initial best corrected visual acuities ranged from hand motion to 20/20. The lesions were located at the central cornea in nine eyes (90%). Smears and cultures from corneal scrapings were obtained from all patients. Four eyes were culture-positive, which included nonfermentative Gram-negative bacillus, Pseudomonas aeruginosa and Acanthamoeba. Positive smears from another two eyes revealed Gram-negative bacilli and double-walled cyst. All patients were cured using antimicrobial medications with complete re-epithelization and disappearance of corneal infiltrates. Four eyes had a final best corrected visual acuity of 20/30 or worse after a mean follow-up of 9.4 months, including one eye that had visual acuity of hand motion only. Complications included corneal opacity in all eyes, glaucoma in one eye, and cataract in one eye.


CONCLUSIONS
Overnight orthokeratology is an important risk factor of microbial keratitis, especially in school children. Acanthamoeba and Gram-negative bacilli, especially Pseudomonas aeruginosa, are the most common pathogens in our series. The risk of microbial keratitis after overnight orthokeratology should not be overlooked.
Tseng
Chia-Hui
CH
Department of Ophthalmology, National Taiwan University Hospital, National Taiwan University, Taipei, Taiwan.
Fong
Chien-Fan
CF
Chen
Wei-Li
WL
Hou
Yu-Chih
YC
Wang
I-Jong
IJ
Hu
Fung-Rong
FR
D000048:Acanthamoeba / Q000302:isolation & purification; D015823:Acanthamoeba Keratitis / Q000188:drug therapy / Q000469:parasitology*; D000293:Adolescent; D000818:Animals; D000890:Anti-Infective Agents / Q000627:therapeutic use; D000981:Antiprotozoal Agents / Q000627:therapeutic use; D001251:Astigmatism / Q000628:therapy; D002648:Child; D003261:Contact Lenses / Q000009:adverse effects*; D003315:Cornea / Q000382:microbiology / Q000469:parasitology; D003320:Corneal Ulcer / Q000188:drug therapy / Q000382:microbiology*; D004359:Drug Therapy, Combination; D015818:Eye Infections, Bacterial / Q000188:drug therapy / Q000209:etiology*; D005260:Female; D006090:Gram-Negative Bacteria / Q000302:isolation & purification; D006801:Humans; D008297:Male; D009216:Myopia / Q000628:therapy; D012307:Risk Factors; D016896:Treatment Outcome; D014792:Visual Acuity
D000890:Anti-Infective Agents; D000981:Antiprotozoal Agents