Eyelid skin disinfecting and conjunctival bacteria in cataract surgery.

PURPOSE: To evaluate the effect on conjunctival micro-organisms of chlorhexidine alcohol 0.5% eyelid wash in cataract patients. METHODS: In this single-centre experimental study, 120 patients scheduled to undergo cataract operation were cultured in the conjunctiva before the operation and after the insertion of the intraocular lens. Bacterial samples for aerobic and anaerobic cultures were taken with a polyvinyl alcohol pad and transported in peptone water to the microbiological laboratory where they were analysed in a blinded fashion. Half of the patients received a standardized eyelid scrub with chlorhexidine alcohol 0.5%, while the rest did not. The conjunctiva of all patients was rinsed preoperatively with chlorhexidine solution 0.05%. RESULTS: In all the between-group comparisons, the treated eyelid group had slightly lower bacterial counts than the control group on the postoperative samples, but differences were far from statistically significant. Within-group comparisons revealed statistically significant reduction in colonies and species between the preoperative and postoperative sampling. CONCLUSION: In this experimental culture study, no evidence was found to suggest that preoperative eyelid chlorhexidine alcohol wash is effective in further reducing bacterial counts in the conjunctiva when the conjunctiva itself is rinsed preoperatively with chlorhexidine solution. The present results, however, do not contradict that the wash may be of some marginal help in reducing bacterial contamination of the operation field. Consequently, this part of the prophylactic protocol is still in practice in our institution.

Prophylactic intracameral cefuroxime. Efficacy in preventing endophthalmitis after cataract surgery.

PURPOSE: To evaluate the efficacy of prophylactic intracameral cefuroxime in preventing endophthalmitis in cataract surgery. SETTING: Department of Ophthalmology, St. Eriks Hospital, Stockholm, Sweden. METHODS: In a noncontrolled retrospective observational study, all cases of recorded postoperative endophthalmitis were related to the total number of uncombined cataract procedures from January 1996 to December 2000. RESULTS: Twenty cases of postoperative endophthalmitis occurred in 32180 procedures, yielding an overall rate of 0.06%. Cefuroxime-resistant organisms accounted for 12 of 13 culture-positive cases, and enterococci were the most common etiology. CONCLUSIONS: Intracameral cefuroxime 1 mg appeared to effectively inhibit sensitive bacterial strains and was associated with a low frequency of postoperative endophthalmitis. The causative organisms of future incidents of postoperative endophthalmitis will determine whether the present protocol must be reappraised.

Prophylactic intracameral cefuroxime. Evaluation of safety and kinetics in cataract surgery.

PURPOSE: To evaluate the safety and kinetics of prophylactic intracameral cefuroxime in cataract surgery. SETTING: Department of Ophthalmology, St. Eriks Hospital, Stockholm, Sweden. METHODS: In a nonrandomized observer-masked best-case trial, the visual rehabilitation and the evolution of laser flare intensity and corneal endothelial cell density after cataract surgery were assessed in 45 patients receiving intracameral cefuroxime and in 45 control patients. Immunoglobulin E-mediated sensitivity was evaluated using a skin prick test to cefuroxime in a screening program comprising all cataract patients operated on in 1997. Intracameral concentrations of cefuroxime in samples retrieved 30 seconds (n = 10) and 1 hour (n = 9) postoperatively were evaluated in an observer-masked fashion with a microbiological assay. RESULTS: Intracameral cefuroxime did not have a statistically significant effect on postoperative visual acuity, induced laser flare intensity, or endothelial cell loss compared with nonadministration of intracameral antibiotic prophylaxis. Three positive skin prick tests to cefuroxime were found in the 5813 screened cataract patients. The median aqueous humor concentration of cefuroxime at 30 seconds was 2742 mg/L, declining to 756 mg/L 1 hour after drug instillation. CONCLUSIONS: Intracameral cefuroxime 1 mg appears safe in terms of local toxicity. Immunoglobulin E-mediated allergy to cefuroxime is rare in the cataract population. The treatment achieved high aqueous concentrations even 1 hour after surgery.

Similar T helper Th2-like cytokine mRNA expression in vernal keratoconjunctivitis regardless of atopic constitution.

BACKGROUND: Many patients with vernal keratoconjunctivitis (VKC), a severe chronic allergic eye disease in children, exhibit IgE-sensitization, but about 40% of cases lack this immunologic trait. As a disease factor in VKC, IgE is thus not fully understood. The aim of this study was to investigate whether there are any differences in the conjunctival cytokine messenger (m)RNA pattern related to IgE-sensitization in children suffering from VKC. METHODS: Tissue samples were obtained from 16 symptomatic VKC subjects with sub-tarsal disease and six control subjects. Expression of mRNA for interleukin (IL)-4, IL-5, IL-13, and interferon (IFN)-gamma was investigated with a semiquantitative reverse-transcriptase polymerase chain reaction (RT-PCR) technique. The presence of T cells, IgE+ cells, mast cells, and eosinophils was analyzed with immunohistochemical methods. Allergen-specific IgE antibodies were assessed in serum and with skin prick testing. RESULTS: Ten out of the 16 VKC subjects showed evidence of IgE-sensitization. No differences were detected for any tissue variable between VKC subjects with and without IgE-sensitization. Statistically significant increases over controls were found for both VKC groups with regard to all cell markers. CONCLUSIONS: The amount of messenger RNA encoding cytokines and inflammatory cell markers in VKC did not correlate with IgE-sensitization. Tissue changes in all patient samples were characterized by a prevalence of T cells, eosinophils, mast cells and cell-bound IgE molecules. However, the role of cell-bound IgE molecules in VKC patients lacking IgE-sensitization remains to be determined.