A novel cell-associated protection assay demonstrates the ability of certain antibiotics to protect ocular surface cell lines from subsequent clinical Staphylococcus aureus challenge.

In vivo effectiveness of topical antibiotics may depend on their ability to associate with epithelial cells to provide continued protection, but this contribution is not measured by standard antibiotic susceptibility tests. We report a new in vitro method that measures the ability of test antibiotics azithromycin (AZM), erythromycin (ERY), tetracycline (TET), and bacitracin (BAC) to associate with mammalian cells and to protect these cells from destruction by bacteria. Mammalian cell lines were grown to confluence using antibiotic-free medium and then incubated in medium containing a single antibiotic (0 to 512 µg/ml). After incubation, the cells were challenged with Staphylococcus aureus ocular isolates, without antibiotics added to the culture medium. Epithelial cell layer integrity was assessed by gentian violet staining, and the minimum cell layer protective concentration (MCPC) of an antibiotic sufficient to protect the mammalian cells from S. aureus was determined. Staining was also quantified and analyzed. Bacterial viability was determined by culture turbidity and growth on agar plates. Preincubation of Chang and human corneal limbal epithelial cells with AZM, ERY, and TET at ≥64 µg/ml provided protection against AZM-susceptible S. aureus strains, with increasing protection at higher concentrations. TET toxicity was demonstrated at >64 µg/ml, whereas AZM displayed toxicity to one cell line at 512 µg/ml. BAC failed to show consistent protection at any dose, despite bacterial susceptibility to BAC as determined by traditional antibiotic susceptibility testing. A range of antibiotic effectiveness was displayed in this cell association assay, providing data that may be considered in addition to traditional testing when determining therapeutic dosing regimens.

The disinfection of contact lenses contaminated with adenovirus.

PURPOSE: We compared the efficacy of different contact lens disinfection systems to eliminate adenovirus. METHODS: Laboratory study evaluating the elimination of adenoviral ocular isolates by contact lens disinfection systems. Hard (gas permeable) and soft contact lenses were contaminated with adenovirus serotypes 8 and 19, and then they were disinfected with chemical, hydrogen peroxide, and heat sterilization systems. The survival of the adenovirus was determined by the shell vial technique. RESULTS: Adenovirus survived chemical and hydrogen peroxide disinfection but not heat sterilization. CONCLUSION: Because heat sterilization is not readily available to sterilize adenovirus contaminated contact lenses, it may be prudent for patients with adenoviral keratoconjunctivitis to dispose of unclean contact lenses.

An in vitro resistance study of levofloxacin, ciprofloxacin, and ofloxacin using keratitis isolates of Staphylococcus aureus and Pseudomonas aeruginosa.

PURPOSE: We compared levofloxacin with ciprofloxacin and ofloxacin using the in vitro susceptibilities of Staphylococcus aureus (SA) and Pseudomonas aeruginosa (PA) keratitis isolates. DESIGN: Retrospective, clinical laboratory study of antibiotic susceptibility among keratitis isolates. PARTICIPANTS: Keratitis isolates from 200 patients with either SA or PA keratitis. METHODS: Minimum inhibitory concentrations (MICs) were determined for levofloxacin, ofloxacin, and ciprofloxacin for 93 SA keratitis isolates (68 fluoroquinolone-resistant and 25 susceptible, as determined by disk diffusion) and 107 PA keratitis isolates (13 fluoroquinolone-resistant and 94 susceptible). National Committee for Clinical Laboratory Standards susceptibilities were determined and analyzed statistically. Time kill studies were determined for fluoroquinolone-susceptible and -resistant isolates to all antibiotics at 8 microg/ml. The killing rates were determined by regression, and the colony count decreases were analyzed. MAIN OUTCOME MEASURES: The susceptibilities and potencies of levofloxacin, ciprofloxacin, and ofloxacin to SA and PA were determined from the MICs. Time kill studies determined the killing rates and decreases in colony counts. RESULTS: The fluoroquinolone-resistant SA susceptibilities to levofloxacin, ofloxacin, and ciprofloxacin were only 22%, 10%, and 3%, respectively. The fluoroquinolone-susceptible SA were 100% susceptible to all antibiotics, with levofloxacin demonstrating the best potency. The fluoroquinolone-resistant PA were resistant to all antibiotics. The fluoroquinolone-susceptible PA isolates were highly susceptible to levofloxacin, ofloxacin, and ciprofloxacin, with ciprofloxacin demonstrating the highest potency. For fluoroquinolone-susceptible SA and PA, the time kill studies determined that the killing rates and decreases in colony counts were equivalent for all three antibiotics tested. The time kill studies demonstrated no colony count decreases for the fluoroquinolone-resistant SA and PA. CONCLUSIONS: Taken together, our susceptibility and time kill data failed to demonstrate convincing differences in the susceptibility of SA and PA keratitis isolates to levofloxacin, ciprofloxacin, and ofloxacin. In general, bacterial isolates that were resistant to ciprofloxacin and ofloxacin were also resistant to levofloxacin.

Lomefloxacin is an effective treatment of experimental bacterial keratitis.

PURPOSE: Lomefloxacin was evaluated as a potential topical therapy for bacterial keratitis. METHODS: Lomefloxacin was compared with ciprofloxacin in different rabbit keratitis models. A total of 216 corneas were infected with Staphylococcus aureus (ciprofloxacin-susceptible and -resistant), Streptococcus viridans, Streptococcus pneumoniae, Pseudomonas aeruginosa, and Serratia marcescens and were treated with lomefloxacin (0.3%), ciprofloxacin (0.3% Ciloxan), and the control phosphate-buffered saline (PBS), respectively. The data were analyzed statistically comparing the decrease in the number of recovered viable bacteria. RESULTS: Compared with PBS-treated control corneas, the colony counts for all bacterial isolates were significantly reduced (p < 0.05) after topical treatment with either lomefloxacin or ciprofloxacin. For gram-positive bacteria, lomefloxacin and ciprofloxacin were equally effective. For gram-negative bacteria, lomefloxacin, while effective, was less so than ciprofloxacin under experimental conditions (p < 0.05). CONCLUSION: Our data, using multiple bacterial keratitis models, suggest that lomefloxacin is promising for therapy of bacterial keratitis. Further clinical studies are needed to expand its use for keratitis therapy.

The survival of herpes simplex virus in multidose office ophthalmic solutions.

PURPOSE: To determine the survival of herpes simplex virus type 1 (HSV-1) in several multidose ophthalmic solutions. METHODS: In three separate trials, 10 aliquots of 5 ml each of three common multidose topical ophthalmic solutions, sodium fluorescein, proparacaine, and nonpreserved artificial tears, were inoculated with 10(5), 10(4), and 10(3) pfu per ml of HSV-1. All samples were titered on A549 cells at various time points for surviving HSV-1. RESULTS: Herpes simplex virus type 1 was not recovered from the fluorescein and proparacaine solutions at 1 hour or any time thereafter, regardless of inoculation titer. Herpes simplex virus type 1 was recovered from the artificial tears up to 7 days. CONCLUSION: Unlike adenovirus, HSV-1 does not survive in preserved fluorescein and proparacaine multidose solutions; therefore, office transmission is highly unlikely.

Emerging fluoroquinolone resistance in bacterial keratitis: a 5-year review.

OBJECTIVE: To identify resistance patterns to the fluoroquinolones for patients with bacterial keratitis. DESIGN: Retrospective observational case series. PARTICIPANTS: All cases of bacterial keratitis presenting to the Charles T. Campbell Ophthalmic Microbiology Laboratory at the Eye and Ear Institute of Pittsburgh from January 1993 to December 1997 were reviewed. A total of 1053 ocular isolates from 825 cases of bacterial keratitis were identified. MAIN OUTCOME MEASURES: In vitro laboratory susceptibility testing of ocular isolates to ciprofloxacin and ofloxacin was determined by the Kirby-Bauer disk diffusion method and interpreted using the National Committee for Clinical Laboratory Standards serum standards. RESULTS: The number of cases of bacterial keratitis per year decreased from 284 in 1993 to 75 in 1997. The ratio of gram-positive to gram-negative organisms changed from 81.8%:18.2% in 1993 to 51.4%:48.6% in 1997 (chi-square, 66.00; degrees of freedom, 4; P < 0.000001). Resistance of Staphylococcus aureus to ciprofloxacin significantly increased annually from 5.8% in 1993 to 35.0% in 1997 (chi-square, 19.80; degrees of freedom, 4; P < 0.0001) and for ofloxacin from 4.7% to 35.0% over the same period (chi-square, 21.32; degrees of freedom, 4; P < 0.001). Streptococcus species and coagulase-negative Staphylococcus species showed significant resistance to both fluoroquinolones but no change in resistance over the study period. The gram-negative organisms showed good susceptibility to the fluoroquinolones. CONCLUSIONS: This in vitro study shows a significant increased resistance of S. aureus to the fluoroquinolones from 1993 to 1997. In addition, gaps in fluoroquinolone coverage for Streptococcus and coagulase-negative Staphylococcus species raise concern for the use of monotherapy in treating bacterial keratitis. Contrary to what might be expected, the distribution of gram-positive to gram-negative organisms has shifted, with a decrease in the number of gram-positive organisms identified, while the number of gram-negative isolates has remained stable.

Evaluation of the shell vial technique for detection of ocular adenovirus. Community Ophthalmologists of Pittsburgh, Pennsylvania.

PURPOSE: The shell vial technique is a cell culture method that uses centrifugation and immunofluorescence to decrease the time required for a positive test. The authors evaluated the shell vial technique as a diagnostic test to detect adenovirus in conjunctival specimens of patients with adenoviral conjunctivitis. DESIGN: Retrospective and prospective case series. PARTICIPANTS: Forty-six patients with adenoviral culture-positive ocular infection. METHODS: The minimum time of incubation (days) that was required for testing clinical isolates with the shell vial was determined with adenovirus serotypes 5 and 8. In a masked retrospective study, 25 true-positive (frozen clinical samples) and 25 true-negative specimens were tested for the presence of adenovirus using the shell vial technique. The 25 true-negative samples included herpes simplex virus, Chlamydia trachomatis, Haemophilus influenzae, Streptococcus pneumoniae, and Staphylococcus aureus. In a prospective study, 21 patients who later tested positive in cell culture for adenovirus were concurrently tested with shell vial. MAIN OUTCOME MEASURES: The time of incubation was determined in days, and the sensitivity, specificity, positive and negative predictive values, and the efficacy of the shell vial test were determined. RESULTS: The minimal time of incubation for testing ocular samples by shell vial was 3 days. In the retrospective study, the sensitivity, specificity, positive predictive value, negative predictive value, and efficacy were 92%, 100%, 100%, 93%, and 96%, respectively. Comparably (P = 0.99), in the prospective study the sensitivity, specificity, positive predictive value, negative predictive value, and efficacy were 95%, 100%, 100%, 96%, and 97%, respectively. The shell vial (93%, 43 of 46) was equivalent (P = 0.42) to cell culture (100%, 46 of 46) for detecting adenovirus, but a positive result was obtained in significantly less time (3 days versus 9.41 +/- 6.23 days) (P = 0.00001). CONCLUSIONS: The shell vial technique was found to be a definitive method for identifying adenovirus from ocular specimens. A clear benefit for the ophthalmologist is that the test can provide a faster positive result (3 days) compared with conventional cell culture, which can take 1 to 3 weeks for adenovirus isolation.

The survival of adenovirus in multidose bottles of topical fluorescein.

PURPOSE: To determine if common ocular adenovirus serotypes survive in vitro in multidose bottles of topical fluorescein (Fluress; Pilkington Barnes Hind, Inc, Sunnyvale, California). METHODS: Clinical isolates of adenovirus types 8 and 19 were inoculated separately into 10 bottles each of Fluress and maintained at room temperature (25 C). All bottles were titered for adenovirus on A549 cell monolayers at 0, 7, 14, 21, 28, and 49 days. RESULTS: Adenovirus was recovered from Fluress for up to 21 days for adenovirus type 19 and 28 days for adenovirus type 8. CONCLUSION: A multidose bottle of Fluress contaminated with adenovirus can be a potential source of adenoviral transmission in an ophthalmic office setting.

Comparison of ciprofloxacin and ofloxacin using human corneal susceptibility levels.

PURPOSE: We compared the in vitro susceptibility of gram-positive bacteria to ciprofloxacin and ofloxacin using human corneal susceptibility levels. METHODS: The concentrations of ciprofloxacin and ofloxacin that can be attained in 99% of human corneas (Cornea99) after topical administration were calculated statistically from reported data. The minimal inhibitory concentrations (MICs) were determined for 95 corneal isolates of gram-positive bacteria (51 Staphylococcus aureus, 16 Streptococcus pneumoniae, 16 Streptococcus viridans group, and 12 coagulase-negative staphylococci). Susceptibility was interpreted by comparing the MICs with the respective Cornea99 for each antibiotic. Time-kill studies of representative gram-positive bacteria were tested using the Cornea99 and the maximal corneal concentrations reported for ciprofloxacin and ofloxacin. RESULTS: The Cornea99 of ciprofloxacin and ofloxacin were calculated to be 3.57 microg/ml (n = 22) and 2.22 microg/ml (n = 20), respectively. The reported mean corneal concentrations of ciprofloxacin (6.90 +/- 6.20 microg/ml) and ofloxacin (5.71 +/- 6.15 microg/ml) were comparable (p = 0.54). All gram-positive bacteria were equally susceptible to ciprofloxacin and ofloxacin (p = 0.54) based on the Cornea99. The time-kill studies determined that 8-24 h were required for both ciprofloxacin and ofloxacin to reach bactericidal levels. CONCLUSION: Ciprofloxacin and ofloxacin demonstrated comparable penetration into the cornea and provided equivalent in vitro efficacy against representative gram-positive bacteria. Time-kill studies indicated that 8-24 h of continual corneal concentrations of ciprofloxacin and ofloxacin were necessary in this study to reduce susceptible gram-positive bacteria by 99.9%.

Time-kill profiles of Enterococcus to antibiotics used for intravitreal therapy.

BACKGROUND AND OBJECTIVE: To determine and then compare the time-kill profiles of Enterococcus to antibiotics used for intravitreal therapy. PATIENTS AND METHODS: The time-kill profiles of four endophthalmitis isolates of Enterococcus faecalis, one vancomycin-resistant E. faecalis isolate, and three vancomycin-resistant isolates of E. faecium were determined against vancomycin, amikacin, cefazolin, gentamicin, ampicillin, ciprofloxacin, ceftazidime, clindamycin, and the combinations of vancomycin and amikacin, vancomycin and ceftazidime, vancomycin and gentamicin, vancomycin and ampicillin, cefazolin and gentamicin, and ampicillin and gentamicin. RESULTS: No single antibiotic or combination was bactericidal (defined as 99.9% kill) to all isolates of Enterococcus. Gentamicin was bactericidal to all E. faecalis isolates. None of the tested antibiotics were bactericidal to vancomycin-resistant E. faecium. CONCLUSIONS: The time-kill profiles demonstrated that vancomycin and ceftazidime did not produce a 99.9% kill for E. faecalis in this small study. Gentamicin combined with either cefazolin or ampicillin had somewhat better bactericidal activity and should be considered as an alternative therapy. Novel therapy may be necessary to treat endophthalmitis because of vancomycin-resistant Enterococcus, depending on the susceptibility patterns of the individual isolate and the response to initial therapy.

Common ocular infections. A prescriber's guide.

While most ocular infections are benign, others can be associated with devastating visual consequences. Most patients present with either ocular discharge, visual symptoms or a red or painful eye. The primary care physician is usually the first to evaluate these patients. We have separated ocular infections into 3 groups. Infections affecting the cornea and conjunctiva often present with eye pain and a red eye; noninfectious aetiologies can have a similar presentation. Infections inside the eye (endophthalmitis) often have devastating consequences. They usually occur following penetrating ocular trauma or after intraocular surgery. Prompt referral to an ophthalmologist is crucial. Infections in the soft tissue surrounding the eye (ocular adnexa and orbit) can involve the eye indirectly and can spread from the orbit into the brain. The purpose of this article is to review ocular infections and current opinion regarding treatment. A general guideline should be that the approach to treatment be governed by the severity of symptoms and the magnitude of possible consequences. Mild external infections can be typically treated empirically. Severe conjunctivitis, and any corneal infection, require aggressive management, often including cultures and broad spectrum antibiotics; cultures are often used to guide treatment. Devastating vision loss can occur, even with aggressive management. Preseptal cellulitis in adults and older children can be managed conservatively with oral antibiotics if the orbit and optic nerve are not involved and the patient is otherwise healthy. Orbital or optic nerve involvement, on the other hand, demands orbital imaging and more aggressive intervention. Patients who have had recent surgery are at risk for developing endophthalmitis. Complaints of pain or a red eye must be taken very seriously. These patients must be considered to have an intraocular infection until it can be ruled out, and should be aggressively managed by a physician trained in eye diseases and surgery.

A 5-year evaluation of the adenoclone test for the rapid diagnosis of adenovirus from conjunctival swabs.

The rapid diagnosis of adenoviral ocular infections affords the opportunity to limit the transmission of virus within the community and avoid expensive, unnecessary, and ineffective therapy. This study evaluated the results of a 5-year experience with the Adenoclone test (Cambridge Biotech, Worcester, MA), an enzyme immunoassay, applied directly to conjunctival swabs obtained from infected eyes. The sensitivity of this test was determined on 372 consecutive adenovirus culture-positive ocular specimens. A subset of 106 specimens was evaluated, including a retrospective chart review to determine the relationship between the Adenoclone result and the time to viral cytopathic effect (CPE) in A549 cell culture, ocular titers (90% tissue culture infectious dose; TCID90), serotype, and associated clinical parameters. Overall, the sensitivity for Adenoclone was 38% (142 of 372), which improved to 65% (129 of 199) for samples positive in culture during the first week. A positive Adenoclone test result was associated with a shorter time to CPE in cell culture (p = 0.0001). The mean ocular titers (log TCID90) associated with a positive test result were found to be at a significantly higher dilution than a negative result (-1.70 +/- 0.93 vs. -0.88 +/- 1.00, p < 0.0001). A positive Adenoclone outcome was independent of the serotype but directly associated with a recent visit to an ophthalmologist's office, follicular conjunctivitis, and conjunctival chemosis. For the rapid diagnosis of adenoviral ocular infections, the Adenoclone test remains useful, but a more sensitive test based on nonradioactive amplification is eagerly anticipated.

Possible consequences of shaking hands with your patients with epidemic keratoconjunctivitis.

PURPOSE: We evaluated patients' hands as a possible vector for the spread of epidemic kerato-conjunctivitis. METHODS: The hands and conjunctivitis of 26 patients with epidemic keratoconjunctivitis and the hands of 26 uninfected control patients were cultured for infectious adenovirus. RESULTS: In 12 (46%) of 26 patients with epidemic keratoconjunctivitis, cultures from the hands were positive for adenovirus, whereas cultures from the hands of all uninfected control patients were negative. CONCLUSIONS: Simultaneous coinfection of patients' hands and eyes with adenovirus may contribute to office epidemics. Ophthalmologists and coworkers should not shake the hands of patients suspected of having epidemic keratoconjunctivitis unless properly gloved.

Fluoroquinolones in the treatment of bacterial keratitis.

PURPOSE: We evaluated the potential role of three topical fluoroquinolones in the treatment of bacterial keratitis by means of a laboratory database. METHODS: Antibiotic susceptibilities were determined for 153 isolates from patients with bacterial keratitis. Results were analyzed for each fluoroquinolone individually and in combination with cefazolin. RESULTS: Predicted susceptibility to each cefazolin-fluoroquinolone combination (98.7%) was superior to that for single-agent therapy with ofloxacin (88.2%), ciprofloxacin (82.3%), or norfloxacin (80.4%) (P = .0002). A cefazolin-fluoroquinolone combination (98.7%) was comparable to a cefazolin-gentamicin combination (97.4%). CONCLUSIONS: Combination therapy with cefazolin and a fluoroquinolone offers a reasonable alternative for the treatment of bacterial keratitis. Single-agent therapy with fluoroquinolones for vision-threatening bacterial keratitis is not advised.

Chlamydia trachomatis can be transmitted by a nonporous plastic surface in vitro.

Chlamydial conjunctivitis is a disease associated with venereal transmission through direct sexual contact or autoinoculation with genital secretions. Appropriate therapy for patients and their sexual partners involves important questions regarding the source of infection and mode of transmission. This study explored the potential role of a fomite, i.e., an environmental surface, as a possible vector of transmission. We determined the in vitro recovery of Chlamydia trachomatis from a nonporous plastic surface under ambient and humid conditions using the standard shell vial technique and confirmation by direct monoclonal immunofluorescence. Under ambient conditions, the TP50 (time at which 50% of samples were positive for Chlamydia) was 5 min, with complete desiccation occurring at 45 min. Under humid conditions, the TP50 was 52.5 min and complete desiccation did not occur up to 3 h. Beyond 45 min, a significantly greater number of positive chlamydial samples were collected under humid conditions (11 of 30) than under ambient conditions (0 of 30) (p = 0.00016). We conclude that a fomite, such as a nonporous plastic surface, may serve as a potential vector for the transmission of chlamydial infection to the eye, especially under humid conditions. This new information may prove useful in counseling patients and their sexual partners.

An in vitro comparison of the susceptibilities of bacterial isolates from patients with conjunctivitis and blepharitis to newer and established topical antibiotics.

This retrospective study compared new and established topical antibiotics with regard to the in vitro susceptibility of bacterial isolates recovered from patients with conjunctivitis (n = 385) and blepharitis (n = 173) using the National Committee for Clinical Laboratory Standards-approved disk diffusion method. The percent susceptibility of recovered isolates to single antibiotic agents or combinations were ranked from greatest to least: chloramphenicol, bacitracin/polymyxin B, ofloxacin, sulfa, ciprofloxacin, trimethoprim/polymyxin B, norfloxacin, gentamicin, bacitracin, trimethoprim, tobramycin, neomycin, erythromycin, and polymyxin B. We determined that none of the available topical antibiotics provided 100% broad spectrum coverage in vitro. Established antibiotics often provided coverage comparable to the newer drugs. Due to the unproven value of in vitro testing as a predictor of clinical outcome in bacterial blepharitis and conjunctivitis, the ophthalmologist should choose therapy based on clinical experience, ongoing critical evaluation of available antibiotics, and cost-effectiveness.

Adenoviral ocular isolates demonstrate serotype-dependent differences in in vitro infectivity titers and clinical course.

The purpose of this study was to evaluate clinical ocular adenoviral isolates for differences among and within serotypes with respect to in vitro infectivity titers and clinical course. The study design included a retrospective chart review and the determination of in vitro infectivity titers (TCID90s) of 90 clinical ocular isolates of various adenoviral serotypes. Adenovirus serotype 8 (AD8) was recovered in significantly greater numbers of patients in the second week of infection compared to all other serotypes (p < 0.002). AD3 and AD4 presented with the highest infectivity titers during the first week of acute infection. Up to 4 logs of variation was demonstrated in TCID90s among isolates of the same serotype. Among the clinical parameters studied, eyelid edema was significantly more common among AD8-infected patients as compared to all other serotypes (p < 0.04). For the first time, specific, but limited serotype differences with respect to infectivity titers and clinical course were demonstrated for adenoviral ocular isolates. Important variations in isolate virulence within a given serotype were also observed.

Evaluation of the polymerase chain reaction test for detecting chlamydial DNA in adult chlamydial conjunctivitis.

PURPOSE: A new polymerase chain reaction (PCR) test (Amplicor, Diagnostics, Branchburg, NJ) was evaluated for its ability to detect chlamydial DNA from previously obtained adult conjunctival specimens. METHODS: The sensitivity of this PCR test was determined on 42 adult conjunctival specimens that were culture-positive for Chlamydia. The specificity was determined by testing 40 true-negative specimens that included 10 normal conjunctival samples and 20 ocular specimens that were culture-positive for herpes simplex virus or adenovirus. The remaining ten samples consisted of ocular bacterial pathogens in chlamydial transport media. RESULTS: Amplicor was 88% (37/42) sensitive and 100% (40/40) specific. CONCLUSIONS: The authors conclude that PCR testing for chlamydial DNA from ocular specimens may be useful, especially when conditions in transport might reduce the yield of positive cultures.

Evaluation of the Kodak Surecell Chlamydia test for the laboratory diagnosis of adult inclusion conjunctivitis.

PURPOSE: The Kodak Surecell Chlamydia test, a rapid enzyme immunoassay, has been reported to be highly sensitive (93%) and specific (96%) for detecting chlamydial lipopolysaccharide antigen in conjunctival specimens from infants, but has not been evaluated previously in adult conjunctival specimens. This study was designed to determine the efficacy of the Kodak Surecell Chlamydia test for the laboratory diagnosis of adult inclusion conjunctivitis. METHODS: Twenty Chlamydia culture-positive conjunctival specimens from adults (true-positives) and 20 true-negative specimens were tested with the Kodak Surecell Chlamydia test. RESULTS: The Kodak Surecell Chlamydia test was 40% (8/20) sensitive, 100% (20/20) specific, and 70% (28/40) efficient. CONCLUSIONS: This study indicates that the Kodak Surecell Chlamydia test, though highly specific, is less sensitive in its ability to diagnose chlamydial conjunctivitis in adults than has been reported previously in infants.

Incidence of adenoviral and chlamydial coinfection in acute follicular conjunctivitis.

PURPOSE/METHODS: After we studied a case of chlamydial and adenoviral coinfection in a 20-year-old woman, we determined the incidence of chlamydial infection in patients with acute adenoviral conjunctivitis. In a randomized retrospective study, we evaluated 100 specimens of patients with culture-proven adenoviral conjunctivitis. RESULTS/CONCLUSIONS: Three of 100 (3%) specimens tested positive for chlamydial DNA using polymerase chain reaction. Adenoviral and chlamydial coinfection is rare, yet should be considered in patients with prolonged follicular keratoconjunctivitis.