Detachment of trophozoites of Acanthamoeba species from soft contact lenses with BEN22 detergent, BioSoak, and Renu multi-purpose solutions.

PURPOSE: BEN22 detergent was studied for its ability to detach Acanthamoeba from soft contact lenses without mechanical cleaning or separate cleaning agents. METHODS: Trophozoites of Acanthamoeba castellanii and A. polyphaga were adhered onto nonionic, high water content soft contact lenses. The lenses were immersed for 2 hours in contact lens care solutions and the remaining trophozoites were counted microscopically. The counts were compared to the counts on the same lens before treatment. RESULTS: BEN22 (50:50 mixture of L-alpha-L-rhamnopyranosyl-beta-hydroxydecanoyl-beta-hydroxydecanoate and 2-O-alpha-L-rhamnopyranosyl-alpha-L-rhamnopyranosyl-beta-hydroxydecanoyl-beta-hydroxydecanoate) (Kassell Industries, Inc., Wisconsin Dells, WI) in a concentration of 0.05% detached the trophozoites to a statistically significant greater extent than saline, but commercial ReNu Multi-Purpose Solution (Bausch & Lomb, Italy) and BioSoak (Finnsusp Ltd., Finland) did so as well. ReNu Multi-Purpose Solution was more effective than 0.005% BEN22 in detaching the trophozoites of both of the Acanthamoeba strains. After the 2 hour immersion period, a maximum of 97% of the initial trophozoites were detached. The variation between individual lenses was significantly greater than that within the different areas of one lens. CONCLUSIONS: BEN22 had no reliable detaching effect on Acanthamoeba. The variation between lenses was great, and the rate of detachment was low with all the agents tested indicating that immersion and rinsing in the solutions tested cannot be considered as a safe substitute for proper disinfection against Acanthamoeba in contact lens care.

Papillary hypertrophy of the upper tarsal conjunctiva during contact lens wear: a 4-month study with ethyl-6-O-decanoyl-glucoside.

PURPOSE: We studied the potential effect of ethyl-6-O-decanoyl-glucoside (EDG) on papillary hypertrophy in contact lens wearers who were recruited on the basis of papillary hypertrophy and a long history of contact lens wear. The contact lens care solutions were 0.00025% chlorhexidine acetate (CHX) with or without 0.005% EDG. METHODS: Nineteen subjects wearing both ionic and non-ionic contact lenses for 6-18 hours used either CHX or CHX+EDG as a cleaning and disinfecting agent. CHX and CHX+EDG was used simultaneously by each subject but in different eyes during two consecutive periods of 8 weeks. Symptoms and signs were recorded at three examinations during the study. The protein content of contact lenses and tryptase activity of tear fluids were measured. RESULTS: The degree of papillary hypertrophy did not decrease in either the CHX or CHX+EDG groups. Also, there were no differences in protein content of lenses nor tryptase activity of tear fluids in either group. There was a significant correlation between papillary hypertrophy and tryptase activity during the study. CONCLUSIONS: Despite the earlier finding that EDG prevents development of papillary hypertrophy in contact lens wearers, EDG still cannot reverse established signs of papillary hypertrophy.

Contact lens care using chlorhexidine acetate with ethyl-6-O-decanoyl-glucoside: a comparative clinical and bacteriological study.

PURPOSE: We compared Ethyl-6-O-decanoyl-glucoside 0.005% (EDG) combined with 0.00025% chlorhexidine acetate (EDGC) to a commercial polyaminpropylbiguanide (PAPB). METHODS: Fifty-nine subjects wearing both ionic and non-ionic contact lenses for 8-16 hours daily used either EDGC or PAPB as a cleaning and disinfectant agent. Neither mechanical nor separate cleaning agents were employed. The study period was for 8 weeks. The following symptoms were compared for each solution: blurred vision, dryness, foreign body sensation, redness, and dirty lenses. The following signs were also compared for each solution: conjunctival hyperemia, papillary hypertrophy, corneal deposits, purulence, limbal vascularization, subepithelial scarring, visual acuity, bulbar hyperemia, and tear breakup time. RESULTS: After 8 weeks, 52% of the subjects in the EDGC group showed no evidence of corneal or conjunctival abnormalities. In contrast, only 19% of the subjects in the PAPB group showed no abnormalities of the conjunctiva or cornea (P = 0.012). After 8 weeks, 25% of the EDGC group showed evidence of papillary hypertrophy, whereas 50% of the PAPB group showed similar findings (P = 0.007). In addition, after 8 weeks of wear, 21% of the subjects using EDGC had positive conjunctival cultures, whereas the rate of positive cultures in the PAPB group was 50% (P = 0.035). At the conclusion of the study, the protein contents of the lenses were 131 micrograms +/- 48 micrograms (N = 29) in the EDGC group and 185 micrograms +/- 65 micrograms (N = 26) in the PAPB group (P = 0.001). CONCLUSION: Subjects using EDGC had fewer pathological findings than subjects using PAPB as their cleaning and disinfecting agent. The mechanism by which EDGC reduced the rate of papillary hypertrophy needs further investigation.

Tear anti-Chlamydia antibodies in males with chlamydial urethritis.

Conjunctival Chlamydia trachomatis was studied in 50 males with chlamydial urethritis. Conjunctival samples from 49 patients were negative for chlamydial antigen by enzyme immunoassay. However, tear anti-Chlamydia IgA antibodies were found in high titers (> or = 400) in 20 out of the 50 patients. Secretory IgA against Chlamydia in corresponding titers was found in 8 patients. The titers differed significantly from those of the 22 negative control subjects. IgG antibodies were not detected. Tear anti-Chlamydia IgA antibodies are not diagnostic for chlamydial conjunctivitis, but occur concomitantly in patients with chlamydial urethritis.