Microbial Bioburden of Orthokeratology Contact Lens Care System.
OBJECTIVE
To assess the bioburden in an orthokeratology contact lens (OK) care system (defined by microbial identification from OK case fluid) and to identify the risk factors causing high bioburden for pediatric OK wearers in southern Taiwan.


METHODS
A prospective study for the investigation of bioburden in the OK care system was performed in a tertiary medical center in southern Taiwan. Microbial isolates from the case fluids soaking OKs were analyzed, and pathogenicity was determined. Age, gender, OK experiences, and contact lens care habits were considered the potential risk factors of microbial bioburden (colony-forming units per milliliter) for causal analysis.


RESULTS
Forty-one OK wearers (20 female and 21 male subjects) participated in this study. The mean age was 12.7 years, and the mean OK-wearing experience was 3.5 years. A total of 86 microbial strains were isolated from 38 culture-positive specimens. Frequently reported pathogens in contact lens-related microbial keratitis were less common in the current study, but still present, including 4 strains (5%) of Serratia marcescens, 1 strain (1%) of Pseudomonas aeruginosa, and 1 strain (1%) of Staphylococcus aureus. Microbial bioburden of the OK care system was significantly higher (P<0.05) in male subjects.


CONCLUSIONS
The contamination rate of the OK care system was high, and many isolated microorganisms had potential pathogenicity. Reinforcement of proper contact lens care and education should be mandatory for OK wearers, particularly for male subjects, to decrease the risk of high bioburden of the OK care system.
Departments of Ophthalmology (J.L., M.-T.K., S.-L.T., Y.-H.L., P.-C.F.); and Laboratory Medicine (C.-C.C.), Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan.
Jung
J
Lo
Ming-Tse
MT
Kuo
Chun-Chih
CC
Chien
Shin-Ling
SL
Tseng
Yu-Hsuan
YH
Lai
Po-Chiung
PC
Fang
D000293:Adolescent; D001419:Bacteria / Q000302:isolation & purification*; D002648:Child; D018639:Contact Lens Solutions; D003263:Contact Lenses, Hydrophilic / Q000382:microbiology*; D004866:Equipment Contamination / Q000706:statistics & numerical data*; D015817:Eye Infections / Q000209:etiology; D005260:Female; D006801:Humans; D008297:Male; D054158:Orthokeratologic Procedures / Q000009:adverse effects / Q000379:methods; D011446:Prospective Studies; D012307:Risk Factors; D013624:Taiwan
D018639:Contact Lens Solutions