Epidemiology and diagnosis of acute conjunctivitis at an inner-city hospital

Microbiological spectrum and antibiotic susceptibility patterns of non-viral conjunctivitis over 16 years at a tertiary eye care center in Southern India

PURPOSE

To determine the trends in the microbial spectrum and antibacterial susceptibility patterns of non-viral conjunctivitis over 16 years.

METHODS

Microbiology data were reviewed from 2006-2021 for all the patients with clinically and culture-proven infectious conjunctivitis. Conjunctival swabs and/or conjunctival scrapings were collected for microbiological workup, and the demographic and antibiotic susceptibility data were extracted from the EMR (Electronic Medical Record). For statistical analysis, χ2-test was performed.

RESULTS

Of the 1711 patients, 814 (47.57%) were culture positive and 897 (52.43%) were culture negative. Of the total culture-proven conjunctivitis cases, 775/814 (95.20%) were bacteria, and 39/814 (4.80%) were fungi. Among these bacterial isolates, 75.74% were gram-positive bacteria, while 24.26% were gram negative. The predominant gram-positive pathogens isolated were S. epidermidis (16.7%), S. aureus (17.9%) (p < 0.05), and S. pneumoniae (18.2%), while Haemophilus spp. (36.2%) (p < 0.05) was the most often isolated gram-negative bacteria (36.2%), and Aspergillus spp. was the most commonly isolated fungus (50%). The susceptibility of gram-positive bacteria to cefazoline increased from 90.46 to 98% (p = 0.01), whereas the susceptibility for gatifloxacin decreased in both gram-positive (81-41%; p < 0.0001) and gram-negative bacteria (73-58%; p = 0.02).

CONCLUSIONS

Increasing resistance of ocular isolates to mainstay antibiotics is a concern, and this data can assist healthcare practitioners in making informed choices regarding the treatment of ocular infections with ophthalmic antibiotics.

Topical Pharmacologic Interventions Versus Active Control, Placebo, or No Treatment for Epidemic Keratoconjunctivitis: Findings From a Cochrane Systematic Review

PURPOSE

To summarize key findings from a Cochrane systematic review of the effectiveness and safety of topical pharmacologic interventions compared with active control or placebo for epidemic keratoconjunctivitis (EKC).

DESIGN

Systematic review.

METHODS

We included randomized controlled trials that compared antiseptic agents, virustatic agents, or immune-modulating topical therapies with placebo or an active control. We adhered to Cochrane methods for trial selection, data extraction, risk of bias evaluation, and data synthesis.

RESULTS

Ten randomized controlled trials with 892 participants with acute or chronic EKC were included. Eight trials compared interventions with artificial tears or saline (n = 4) or with steroids (n = 4); two 3-arm trials contributed data to both comparisons. Estimates suggested that compared with tears, after povidone-iodine (PVP-I) alone (2 studies, 409 participants) more participants with acute EKC had resolution of symptoms (risk ratio [RR] 1.15 [95% confidence interval {CI} 1.07-1.24]) and signs (RR 3.19 [95% CI 2.29-4.45]) within 10 days. In 2 trials comparing treatments with steroid alone or steroid with levofloxacin, fewer eyes treated with PVP-I or polyvinyl alcohol iodine (PVA-I) plus steroid developed subepithelial infiltrates within 21 days (RR 0.08 [95% CI 0.01-0.55]; 69 eyes). No treatment was shown to improve resolution of infiltrates.

CONCLUSIONS

Low- to very low-level certainty of evidence suggested that PVP-I or PVA-I with steroid may confer some benefit in acute EKC, but imprecision from small sample sizes, the potential risk of bias from inadequate reporting or trial design, and variability in participant selection, outcome measurement, and reporting limit the amount and quality of evidence.

Does This Patient With Acute Infectious Conjunctivitis Have a Bacterial Infection?: The Rational Clinical Examination Systematic Review

IMPORTANCE

Acute infectious conjunctivitis is characterized by ocular redness and discharge, and is a common clinical entity. Evidence-based tools to aid the clinical diagnosis of viral vs bacterial conjunctivitis are lacking and may contribute to overprescribing of topical antibiotics.

OBJECTIVE

To determine the relative prevalence of viral vs bacterial conjunctivitis in adults and children, and to determine which symptoms or signs are suggestive of a viral vs bacterial etiology.

DATA SOURCES

A MEDLINE search (January 1946-March 2022) yielded 1891 articles. Included articles were rated using a quality score based on a modified Rational Clinical Examination grading system. Methodological quality levels 1 through 4 required a microbiological reference standard for diagnosis, whereas quality level 5 (the lowest quality) used a clinical reference standard for diagnosis.

STUDY SELECTION

Consecutive series of patients presenting with acute infectious conjunctivitis and case series of viral or bacterial conjunctivitis alone. Thirty-two studies were included in a meta-analysis to determine prevalence and diagnostic accuracy measures; 27 used a microbiological reference standard for diagnosis and 5 used a clinical reference standard for diagnosis.

RESULTS

In studies involving children (5 studies; 881 patients; mean age, 4.7 years [age range, 1 month-18 years]), the prevalence of bacterial conjunctivitis was higher than viral conjunctivitis (71% vs 16%, respectively, P = .01). In the only study of adults (n = 207 patients; mean age, 25.7 years), the prevalence of viral conjunctivitis was higher than bacterial conjunctivitis (78% vs 16%, respectively, P < .001). For the primary analysis of level 1 (n = 6) and level 2 (n = 5) studies (1725 patients total), the clinical findings that best distinguished a viral etiology for conjunctivitis from a bacterial etiology included pharyngitis (sensitivity range, 0.55-0.58; specificity range, 0.89-0.94; positive likelihood ratio [LR] range, 5.4-9.9), preauricular lymphadenopathy (sensitivity range, 0.17-0.31; specificity range, 0.93-0.94; positive LR range, 2.5-5.6), and contact with another person with red eye (sensitivity, 0.18 [95% CI, 0.14-0.22]; specificity, 0.93 [95% CI, 0.90-0.95]; positive LR, 2.5 [95% CI, 1.6-3.7]). Mucopurulent ocular discharge (sensitivity, 0.76 [95% CI, 0.60-0.87); specificity, 0.66 [95% CI, 0.58-0.73]; positive LR, 2.1 [95% CI, 1.7-2.6]) and otitis media (sensitivity, 0.24 [95% CI, 0.20-0.29]; specificity, 0.91 [95% CI, 0.85-0.94]; positive LR, 2.5 [95% CI, 1.5-4.4]) were associated with the presence of bacterial conjunctivitis.

CONCLUSIONS AND RELEVANCE

In this review, bacterial conjunctivitis was more common than viral conjunctivitis in children and viral conjunctivitis was more common than bacterial conjunctivitis in adults, although the prevalence estimates were based on limited evidence. Symptoms and signs associated with a higher likelihood of viral conjunctivitis in adults and children included concomitant pharyngitis, an enlarged preauricular node, and contact with another person with red eye, and signs associated with a higher likelihood of bacterial conjunctivitis included the presence of mucopurulent discharge and otitis media, but no single symptom or sign differentiated the 2 conditions with high certainty.

Survey of state conjunctivitis policies for school-age students

PURPOSE

To examine state policies regarding school-age students with conjunctivitis.

METHODS

Analysis included the following evidence: publicly available policies for disposition of affected students; indications for exclusion and return to classroom; and completeness of information, including mention of different etiologies of conjunctivitis; signs and symptoms of viral versus bacterial conjunctivitis; student disposition and treatment based on etiology; internally consistent recommendations; reference to credible resources; and mention of the possibility of a conjunctivitis outbreak.

RESULTS

Fifteen of 50 states have no policies. Ten states allow students to remain in school, 5 allow return 24 hours after initiation of antibiotic treatment, and 5 require physician approval. Seventeen states and Washington, DC, offer little detail or internally inconsistent recommendations, such as choice of antibiotic use or provider note. Twelve policies are thoroughly presented. Twenty-three states refer to sources like the Centers for Disease Control and Prevention and the American Academy of Pediatrics. No policy references the American Academy of Ophthalmology.

CONCLUSIONS

State policies on conjunctivitis in students vary widely. Antibiotic use as a prerequisite for return to school has drawbacks of cost to parents, increasing antibiotic resistance, and lack of efficacy against nonbacterial etiologies, for example, viral conjunctivitis. Publicly available information and guidelines could be improved, aiming for fewer absentee days, reduced outbreak risk, and reduced risk of antibiotic resistance.

Evaluation of knowledge, attitude, and behaviour of ophthalmologists about adenoviral conjunctivitis transmission and treatment : An online survey for Turkish ophthalmologists

PURPOSE

To determine the prevalence of adenoviral conjunctivitis in Turkish ophthalmologists, to provide an overview of the treatment and prophylaxis of adenoviral conjunctivitis, and to analyze the data in the context of evidence-based treatment recommendations.

METHODS

An online questionnaire consisting of 20 multiple-choice questions about the characteristics of the respondents, the individual adenoviral conjunctivitis history of the ophthalmologists, their practice's approaches, and prescription preferences were emailed to Turkish ophthalmologists.

RESULTS

The survey was emailed to 500 ophthalmologists; 45% of them returned the questionnaire. According to the responses, the history of adenoviral conjunctivitis infections was positive in 46.7% (n: 120), recurrent attack prevalence was 16.2% in ophthalmologists. Lubricants (67.6%) are the most preferred first-line treatment options for adenoviral conjunctivitis, followed by povidone-iodine (59.6%), topical antibiotics (51.1%), topical antivirals (29.3%), topical corticosteroids (26.7%), and topical nonsteroidal anti-inflammatory agents (19.6%). A total of 98.2% preferred to dismiss infected patients. The preferred prophylaxis options were frequent hand washing/use of gloves (97.8%), disinfection of medical devices (95.1%), isolation of infected patients (79.1%), hand hygiene with gemicides (58.7%). The percentage of single-dose eye drop selection was 46.2.

CONCLUSIONS

The findings of this survey showed that most Turkish ophthalmologists generally follow international guidelines for the treatment of adenoviral conjunctivitis. The treatment algorithm is still controversial, so ophthalmologists should be aware of treatment guideline updates in line with evidence-based recommendations. Having sufficient knowledge of the basic characteristics of viruses is important to control the spread of the disease.

Topical pharmacologic interventions versus placebo for epidemic keratoconjunctivitis

BACKGROUND

Viruses cause about 80% of all cases of acute conjunctivitis. Human adenoviruses are believed to account for 65% to 90% of cases of viral conjunctivitis, or 20% to 75% of all causes of infectious keratoconjunctivitis worldwide. Epidemic keratoconjunctivitis (EKC) is a highly contagious subset of adenoviral conjunctivitis that has been associated with large outbreaks at military installations and at medical facilities. It is accompanied by severe conjunctival inflammation, watery discharge, and light sensitivity, and can lead to chronic complications such as corneal and conjunctival scarring with discomfort and poor quality of vision. Due to a lack of consensus on the efficacy of any pharmacotherapy to alter the clinical course of EKC, no standard of care exists, therefore many clinicians offer only supportive care.

OBJECTIVES

To assess the efficacy and safety of topical pharmacological therapies versus placebo, an active control, or no treatment for adults with EKC.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL, which contains the Cochrane Eyes and Vision Trials Register; 2021, Issue 4); Ovid MEDLINE; Ovid Embase; Latin American and Caribbean Health Sciences database (LILACS); ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP), with no restrictions on language or year of publication. The date of the last search was 27 April 2021.

SELECTION CRITERIA

We included randomized controlled trials in which antiseptic agents, virustatic agents, or topical immune-modulating therapy was compared with placebo, an active control, or no treatment.

DATA COLLECTION AND ANALYSIS

We used standard Cochrane methodology.

MAIN RESULTS

We identified 10 studies conducted in Asia, Europe, the Middle East, and North Africa with a total of 892 participants who were treated for 7 days to 6 months and followed for 7 days up to 1.5 years. Study characteristics and risk of bias In most studies participants were predominantly men (range: 44% to 90%), with an age range from 9 to 82 years. Three studies reported information on trial registration, but we found no published study protocol. The majority of trials had small sample sizes, ranging from 18 to 90 participants enrolled per study; the only exception was a trial that enrolled 350 participants. We judged most studies to be at high or unclear risk of bias across risk of bias domains. Findings We included 10 studies of 892 EKC participants and estimated combined intervention effects in analyses stratified by steroid-containing control treatment or artificial tears. Six trials contributed to the comparisons of topical interventions (povidone-iodine [PVP-I], trifluridine, ganciclovir, dexamethasone plus neomycin) with artificial tears (or saline). Very low certainty evidence from two trials comparing trifluridine or ganciclovir with artificial tears showed inconsistent effects on shortening the mean duration of cardinal symptoms or signs of EKC. Low certainty evidence based on two studies (409 participants) indicated that participants treated with PVP-I alone more often experienced resolution of symptoms (risk ratio (RR) 1.15, 95% confidence interval (CI) 1.07 to 1.24) and signs (RR 3.19, 95% CI 2.29 to 4.45) during the first week of treatment compared with those treated with artificial tears. Very low certainty evidence from two studies (77 participants) suggested that PVP-I or ganciclovir prevented the development of subepithelial infiltrates (SEI) when compared with artificial tears within 30 days of treatment (RR 0.24, 95% CI 0.10 to 0.56). Four studies compared topical interventions (tacrolimus, cyclosporin A [CsA], trifluridine, PVP-I + dexamethasone) with topical steroids, and one trial compared fluorometholone (FML) plus polyvinyl alcohol iodine (PVA-I) with FML plus levofloxacin. Evidence from one trial showed that more eyes receiving PVP-I 1.0% plus dexamethasone 0.1% had symptoms resolved by day seven compared with those receiving dexamethasone alone (RR 9.00, 95% CI 1.23 to 66.05; 52 eyes). In two trials, fewer eyes treated with PVP-I or PVA-I plus steroid developed SEI within 15 days of treatment compared with steroid alone or steroid plus levofloxacin (RR 0.08, 95% CI 0.01 to 0.55; 69 eyes). One study found that CsA was no more effective than steroid for resolving SEI within four weeks of treatment (RR 0.84, 95% CI 0.67 to 1.06; N = 88). The evidence from trials comparing topical interventions with steroids was overall of very low level certainty. Adverse effects Antiviral or antimicrobial agents plus steroid did not differ from artificial tears in terms of ocular discomfort upon instillation (RR 9.23, 95% CI 0.61 to 140.67; N = 19). CsA and tacrolimus eye drops were associated with more cases of severe ocular discomfort, and sometimes intolerance, when compared with steroids (RR 4.64, 95% CI 1.15 to 18.71; 2 studies; N = 141). Compared with steroids, tacrolimus did not increase the risk of elevated intraocular pressure (RR 0.07, 95% CI 0 to 1.13; 1 study; N = 80), while trifluridine conferred no additional risk compared to tear substitute (RR 5.50, 95% CI 0.31 to 96.49; 1 study; N = 97). Overall, bacterial superinfection was rare (one in 23 CsA users) and not associated with use of the intervention steroid (RR 3.63, 95% CI 0.15 to 84.98; N = 51). The evidence for all estimates was of low or very low certainty.

AUTHORS' CONCLUSIONS

The evidence for the seven specified outcomes was of low or very low certainty due to imprecision and high risk of bias. The evidence that antiviral agents shorten the duration of symptoms or signs when compared with artificial tears was inconclusive. Low certainty evidence suggests that PVP-I alone resolves signs and symptoms by seven days relative to artificial tears. PVP-I or PVA-I, alone or with steroid, is associated with lower risks of SEI development than artificial tears or steroid (very low certainty evidence). The currently available evidence is insufficient to determine whether any of the evaluated interventions confers an advantage over steroids or artificial tears with respect to virus eradication or its spread to initially uninvolved fellow eyes. Future updates of this review should provide evidence of high-level certainty from trials with larger sample sizes, enrollment of participants with similar durations of signs and symptoms, and validated methods to assess short- and long-term outcomes.

A Systematic Review of Clinical Practice Guidelines for Infectious and Non-infectious Conjunctivitis

PURPOSE

To systematically review and critically appraise clinical practice guidelines (CPGs) and summarise the recommendations for non-infectious and infectious conjunctivitis.

METHODS

CPGs published on non-infectious and infectious conjunctivitis between 2010 and March 2020 were reviewed, evaluated, and selected using nine items from the Appraisal of Guidelines for Research and Evaluation II tool (4, 7, 8, 10, 12, 13, 15, 22 and 23). CPGs with an average score for items 4, 7, 8, 12, or 22 below 3 and/or a sum of the two researchers' average score for all nine items less than 45 were excluded. Two authors independently extracted and validated the data using standardised forms.

RESULTS

Fifteen CPGs from five sources remained for data extraction. CPGs consistently recommended non-pharmacological interventions (artificial tears, cold compress, avoidance or removal of allergens) for non-infectious conjunctivitis and pharmacological interventions (topical anti-histamine, mast-cell stabiliser and dual-acting agent) for allergy types. Observation without treatment was strongly recommended for non-herpetic viral and bacterial infections. Systemic and topical anti-viral was consistently recommended for herpetic viral conjunctivitis, while systemic and topical antibiotics were recommended for chlamydial and gonorrhoeal conjunctivitis. The methods used to assess the level of evidence and the strength of recommendation varied among CPGs.

CONCLUSIONS

There are a number of high-quality CPGs for non-infectious and infectious conjunctivitis. While there were a number of consistencies in the recommendations provided within these CPGs, several inconsistencies were also identified. Many of which related to the scope of practise of the targeted end-user of the particular guideline.

Predictive Accuracy and Densitometric Analysis of Point-of-Care Immunoassay for Adenoviral Conjunctivitis

Purpose

Accurate diagnosis of adenoviral conjunctivitis (Ad-Cs) is important for timely and appropriate patient management to reduce disease transmission. This study assessed the diagnostic accuracy of a commercially available point-of-care adenovirus immunoassay and determined whether its predictive accuracy is influenced by signal intensities of test result bands.

Methods

Point-of-care immunoassay (AdenoPlus) testing and quantitative polymerase chain reaction (qPCR) testing was performed on conjunctival swab samples obtained from eyes of 186 eligible adult participants with presumed infectious conjunctivitis and symptoms of ≤4 days. Masked observers assessed signal intensities of the immunoassay test and control bands using densitometry.

Results

Ad-Cs was confirmed by qPCR in 28 of the 56 eyes that tested positive on the AdenoPlus, a 50% positive predictive value (95% confidence interval [CI] = 36.9, 63.1). No adenovirus was detected by qPCR in 128 of 130 eyes that tested negative on AdenoPlus, a 98.5% negative predictive value (CI = 96.3, 100). Sensitivity and specificity were 93% (CI = 84.4, 100) and 82% (CI = 76.0, 88.1), respectively. Viral titers significantly correlated with ratio of test band signal intensities (R² = 0.32, P = 0.002). Higher positive predictive value was associated with higher densitometry ratios (receiver operating characteristic [ROC] area = 0.71; 95% CI = 0.59, 0.83).

Conclusions

Densitometric analyses suggest that the diagnostic accuracy of AdenoPlus is influenced by the signal intensity of the test result bands. Visual comparison of the test band intensities by clinicians could reduce the false positive rate of point-of-care immunoassays and aid in the diagnosis of viral infections.

Translational Relevance

Ratiometric densitometry of point-of-care immunoassays could aid clinicians’ decision making in diagnosing infectious diseases, including Ad-Cs.

Conjunctivitis: A Systematic Review

Conjunctivitis is a commonly encountered condition in ophthalmology clinics throughout the world. In the management of suspected cases of conjunctivitis, alarming signs for more serious intraocular conditions, such as severe pain, decreased vision, and painful pupillary reaction, must be considered. Additionally, a thorough medical and ophthalmic history should be obtained and a thorough physical examination should be done in patients with atypical findings and chronic course. Concurrent physical exam findings with relevant history may reveal the presence of a systemic condition with involvement of the conjunctiva. Viral conjunctivitis remains to be the most common overall cause of conjunctivitis. Bacterial conjunctivitis is encountered less frequently and it is the second most common cause of infectious conjunctivitis. Allergic conjunctivitis is encountered in nearly half of the population and the findings include itching, mucoid discharge, chemosis, and eyelid edema. Long-term usage of eye drops with preservatives in a patient with conjunctival irritation and discharge points to the toxic conjunctivitis as the underlying etiology. Effective management of conjunctivitis includes timely diagnosis, appropriate differentiation of the various etiologies, and appropriate treatment.

Chlamydia Conjunctivitis in 2 Prepubertal Children: An Uncommon Presentation of Child Sexual Abuse

Sexually transmitted infection as the result of child sexual abuse in prepubertal children is uncommon. Chlamydia trachomatis conjunctivitis is an even less common entity in prepubertal children outside the newborn period. This report details the presentation of 2 children with conjunctivitis who were subsequently diagnosed as having C. trachomatis conjunctivitis. One child was also diagnosed as having rectal and pharyngeal C. trachomatis infection, and the other also had genital C. trachomatis infection. Even with multisite C. trachomatis infection as an indication of sexual abuse, neither child gave a detailed disclosure of abuse to account for their infections. The absence of a clear disclosure is not uncommon. Previous literature reports that a disclosure in these circumstances occurs in less than half of cases. In this report, we review the recommendations for diagnosis of C. trachomatis using nucleic acid amplification testing and culture as well as treatment. Specific clinical features should alert the clinician to C. trachomatis conjunctivitis and lead to timely diagnosis and protection of the child from further sexual abuse.

A Pyrrhic Victory: The PMN Response to Ocular Bacterial Infections

Some tissues of the eye are susceptible to damage due to their exposure to the outside environment and inability to regenerate. Immune privilege, although beneficial to the eye in terms of homeostasis and protection, can be harmful when breached or when an aberrant response occurs in the face of challenge. In this review, we highlight the role of the PMN (polymorphonuclear leukocyte) in different bacterial ocular infections that invade the immune privileged eye at the anterior and posterior segments: keratitis, conjunctivitis, uveitis, and endophthalmitis. Interestingly, the PMN response from the host seems to be necessary for pathogen clearance in ocular disease, but the inflammatory response can also be detrimental to vision retention. This "Pyrrhic Victory" scenario is explored in each type of ocular infection, with details on PMN recruitment and response at the site of ocular infection. In addition, we emphasize the differences in PMN responses between each ocular disease and its most common corresponding bacterial pathogen. The in vitro and animal models used to identify PMN responses, such as recruitment, phagocytosis, degranulation, and NETosis, are also outlined in each ocular infection. This detailed study of the ocular acute immune response to infection could provide novel therapeutic strategies for blinding diseases, provide more general information on ocular PMN responses, and reveal areas of bacterial ocular infection research that lack PMN response studies.

Resistant Infantile Bacterial Conjunctivitis in Egypt: A Microbiology Study

PURPOSE

To study the microbiological aspects of infantile bacterial conjunctivitis resistant to empirical topical antibiotic therapy in Egypt.

METHODS

Ninety-two eyes of 86 infants with bacterial conjunctivitis were included in this prospective study. They all failed to show evidence of clinical improvement after 2 weeks of empirical topical antibiotic therapy. Conjunctival swabs were obtained from all patients for bacterial culture and antibiotic sensitivity testing.

RESULTS

The age of the participants ranged from 4 to 6 months. Culture results revealed infection with a solitary organism in 48.9% of eyes. Mixed bacterial growth was reported in 47.8% of eyes, whereas 3.3% of eyes showed no bacterial growth. The most commonly isolated organisms were Staphylococcus aureus, Streptococcus pneumoniae, and Pseudomonas aeruginosa. These organisms were highly sensitive to fluoroquinolones (levofloxacin, ciprofloxacin, ofloxacin, and norfloxacin), followed by chloramphenicol, vancomycin, and amikacin, and were resistant to carbapenems (imipenem and meropenem), fusidic acid, and pipracellin.

CONCLUSIONS

Bacterial culture and antibiotic sensitivity testing provides beneficial diagnostic and therapeutic information when dealing with infantile resistant bacterial conjunctivitis. [J Pediatr Ophthalmol Strabismus. 2018;55(2):135-139.].

Molecular identification of viral agents associated with acute conjunctivitis: a prospective controlled study

Background

Viral conjunctivitis are the most frequent infections in ophthalmology clinics. The diagnosis is usually relying on clinical findings and medical history. However, topical antibiotics are often used unnecessarily addition to symptomatic treatment because of unsure agents. We aimed to detect the Adenovirus, Coxsackievirus and Enterovirus from conjunctiva and pharyngeal samples of patients.

Methods

The conjunctiva and pharyngeal samples of the patients with conjunctivitis were taken by Virocult transport media and kept at −80 ̊C up to study day. Adenovirus spp, Enterovirus 70 and Enterovirus 71, Coxsackie A24 and Coxsackie A16 were detected by real-time PCR. Samples from healthy health care workers of ophthalmology clinic were used for control group.

Results

A total of 176 samples (conjunctival and pharyngeal samples of 62 patient and 26 healthy subjects) were included. The mean age of 34 (55.7%) male and 27 (44.3%) female patients was 34 ± 17. Twenty five (40.3%) of the patients were receiving antibiotic drops at first visit. The main etiologic agent in conjunctival samples was found to be Adenovirus (46/62, 74.2%) followed by Enterovirus 70 (4/62, 6.4%) and Enterovirus 71 (4/62, 6.4%). Coxsackievirus 16 and 24 were also found in 2 patients (1/62 each, 1.6%). Pharyngeal samples were also positive for Adenovirus (20/62, 32.3%), Enterovirus 70 and 71 (7/62, 11.3% and 5/62, 8.1% respectively), Coxsackievirus 16 and 24 (2/62, 3.2% and 1/61, 1.6%).

Conclusions

It is very difficult in viral conjunctivitis to make clinical differentiation caused by different agents because of common clinical signs and symptoms. In routine clinical work, the viral conjunctivitis usually related with Adenovirus. But almost one fourth of the patients’ conjunctivitis were not related to Adenovirus, which shows the importance of the laboratory diagnostics. True diagnosis plays an important role on prevention of contamination and unnecessary use of antibiotics in viral conjunctivitis.

Application of Box-Behnken design for preparation of levofloxacin-loaded stearic acid solid lipid nanoparticles for ocular delivery: Optimization, in vitro release, ocular tolerance, and antibacterial activity

The aim of the present study was to develop and optimize levofloxacin loaded solid lipid nanoparticles for the treatment of conjunctivitis. Box-Behnken experimental design was applied for optimization of solid lipid nanoparticles. The independent variables were stearic acid as lipid (X1), Tween 80 as surfactant (X2) and sodium deoxycholate as co-surfactant (X3) while particle size (Y1) and entrapment efficiency (Y2) were the dependent variables. Further in vitro release and antibacterial activity in vitro were also performed. The optimized formulation of levofloxacin provides particle size of 237.82 nm and showed 78.71% entrapment efficiency and achieved flux 0.2,493 μg/cm(2)/h across excised goat cornea. In vitro release study showed prolonged drug release from the optimized formulation following Korsmeyer-Peppas model. Antimicrobial study revealed that the developed formulation possesses antibacterial activity against Staphylococcus aureus, and Escherichia coli equivalent to marketed eye drops. HET-CAM test demonstrated that optimized formulation was found to be non-irritant and safe for topical ophthalmic use. Our results concluded that solid lipid nanoparticles are an efficient carrier for ocular delivery of levofloxacin and other drugs.

The prevalence of adenoviral conjunctivitis at the Clinical Hospital of the State University of Campinas, Brazil

OBJECTIVES

Viral conjunctivitis is a common, highly contagious disease that is often caused by an adenovirus. The aim of this study was to evaluate the prevalence of adenoviral conjunctivitis by analyzing data from a prospective clinical study of 122 consecutively enrolled patients who were treated at the Clinical Hospital of the State University of Campinas (UNICAMP) after a clinical diagnosis of infectious conjunctivitis between November 2011 and June 2012.

METHODS

Polymerase chain reaction was used to evaluate all cases of clinically diagnosed infectious conjunctivitis and based on the laboratory findings, the prevalence of adenoviral infections was determined. The incidence of subepithelial corneal infiltrates was also investigated.

RESULTS

Of the 122 patients with acute infectious conjunctivitis included, 72 had positive polymerase chain reaction results for adenoviruses and 17 patients developed subepithelial corneal infiltrates (13.93%).

CONCLUSIONS

The polymerase chain reaction revealed that the prevalence of adenoviral conjunctivitis was 59% in all patients who presented with a clinical diagnosis of infectious conjunctivitis from November 2011 to June 2012. The prevalence of adenoviral conjunctivitis in the study population was similar to its prevalence in other regions of the world.

Bedside Diagnosis of the 'Red Eye': A Systematic Review

BACKGROUND

In patients with red eye, traditional teachings suggest that photophobia, visual blurring, and eye pain indicate serious eye disease; in patients with presumed conjunctivitis, the finding of purulent drainage traditionally indicates a bacterial cause. The accuracy of these teachings is unknown.

METHODS

A MEDLINE search was performed to retrieve articles published between 1966 and April 2014 relevant to the bedside diagnosis of serious eye disease and bacterial conjunctivitis.

RESULTS

In patients with red eye, the most useful findings indicating serious eye disease are anisocoria (with the smaller pupil in the red eye and difference between pupil diameters >1 mm; likelihood ratio [LR], 6.5; 95% confidence interval [CI], 2.6-16.3) and photophobia, elicited by direct illumination (LR, 8.3; 95% CI, 2.7-25.9), indirect illumination (LR, 28.8; 95% CI, 1.8-459), or near synkinesis test ("finger-to-nose convergence test," LR, 21.4; 95% CI, 12-38.2). In patients with presumed conjunctivitis, complete redness of the conjunctival membrane obscuring tarsal vessels (LR, 4.6; 95% CI, 1.2-17.1), observed purulent discharge (LR, 3.9; 95% CI, 1.7-9.1), and matting of both eyes in the morning (LR, 3.6; 95% CI, 1.9-6.5) increase the probability of a bacterial cause; failure to observe a red eye at 20 feet (LR, 0.2; 95% CI, 0-0.8) and absence of morning gluing of either eye (LR, 0.3; 95% CI, 0.1-0.8) decrease the probability of a bacterial cause.

CONCLUSIONS

Several bedside findings accurately distinguish serious from benign eye disease in patients with red eye and, in patients with presumed conjunctivitis, distinguish bacterial from viral or allergic causes.

Clinical and Antibacterial Efficacy and Safety of Besifloxacin Ophthalmic Suspension Compared With Moxifloxacin Ophthalmic Solution

PURPOSE

To evaluate the efficacy of besifloxacin ophthalmic suspension 0.6% compared with moxifloxacin ophthalmic solution 0.5% in the treatment of bacterial conjunctivitis in an Indian population.

DESIGN

Multicenter, randomized, double-masked, active-controlled, parallel-group, clinical trial, including 6 clinical sites in India.

METHODS

Patients were randomized to receive 1 drop of besifloxacin or moxifloxacin in the infected eye(s), 3 times daily, for 5 days. Primary efficacy end points included clinical resolution and bacterial eradication at day 5. Secondary efficacy end points included clinical resolution and bacterial eradication at day 8, ocular discharge, bulbar conjunctival injection, investigator's global assessment, and bacterial eradication by species. Efficacy was analyzed using the Cochran-Mantel-Haenszel and Pearson χ2 tests. Safety was assessed by the incidence of ocular and nonocular treatment-emergent adverse events (AEs), changes in visual acuity, and biomicroscopy and ophthalmoscopy findings. Data presented are that for the subset of patients from India.

RESULTS

Of the 123 patients randomized at clinical sites in India, 96.7% completed the study. Day 5 differences in microbial eradication (100% besifloxacin vs 96.3% moxifloxacin) and in clinical resolution (78.9% besifloxacin vs 71.4% moxifloxacin) were not statistically significant. No statistically significant between-group differences were observed for secondary end points. All ocular AEs in both groups were mild or moderate in severity. There were no drug-related ocular AEs with besifloxacin.

CONCLUSIONS

Treatment of bacterial conjunctivitis with besifloxacin 0.6% produces similar antibacterial and clinical efficacy as that with moxifloxacin 0.5% in an Indian population, with no clinically meaningful safety concerns.

Conjunctivitis: a systematic review of diagnosis and treatment

IMPORTANCE

Conjunctivitis is a common problem.

OBJECTIVE

To examine the diagnosis, management, and treatment of conjunctivitis, including various antibiotics and alternatives to antibiotic use in infectious conjunctivitis and use of antihistamines and mast cell stabilizers in allergic conjunctivitis.

EVIDENCE REVIEW

A search of the literature published through March 2013, using PubMed, the ISI Web of Knowledge database, and the Cochrane Library was performed. Eligible articles were selected after review of titles, abstracts, and references.

FINDINGS

Viral conjunctivitis is the most common overall cause of infectious conjunctivitis and usually does not require treatment; the signs and symptoms at presentation are variable. Bacterial conjunctivitis is the second most common cause of infectious conjunctivitis, with most uncomplicated cases resolving in 1 to 2 weeks. Mattering and adherence of the eyelids on waking, lack of itching, and absence of a history of conjunctivitis are the strongest factors associated with bacterial conjunctivitis. Topical antibiotics decrease the duration of bacterial conjunctivitis and allow earlier return to school or work. Conjunctivitis secondary to sexually transmitted diseases such as chlamydia and gonorrhea requires systemic treatment in addition to topical antibiotic therapy. Allergic conjunctivitis is encountered in up to 40% of the population, but only a small proportion of these individuals seek medical help; itching is the most consistent sign in allergic conjunctivitis, and treatment consists of topical antihistamines and mast cell inhibitors.

CONCLUSIONS AND RELEVANCE

The majority of cases in bacterial conjunctivitis are self-limiting and no treatment is necessary in uncomplicated cases. However, conjunctivitis caused by gonorrhea or chlamydia and conjunctivitis in contact lens wearers should be treated with antibiotics. Treatment for viral conjunctivitis is supportive. Treatment with antihistamines and mast cell stabilizers alleviates the symptoms of allergic conjunctivitis.

Conjunctivitis: systematic approach to diagnosis and therapy

Conjunctivitis is a common problem in primary health care. Inflammation of the conjunctiva may result from infection or noninfectious causes. Microbial conjunctivitis may be caused by bacteria, viruses, or parasites. Although usually a benign, self-limited disease in healthy individuals, serious complications (eg, keratitis) may be sight-threatening. Accurate diagnosis and specific treatment of conjunctivitis remain challenging. History taking and physical examination are occasionally insufficient for correct diagnosis, thus laboratory testing may play a vital role in identification of specific pathogen(s). However, diagnostic testing has several limitations, including time-consuming methods, increased cost, and requirement for expertise in performance and interpretation. Treatment with empirical topical antibiotics for suspected infectious conjunctivitis is controversial. Although antibiotic treatment can diminish risk of adverse events and shorten the course of disease, drug resistance, toxicity, and expense are important considerations in management of acute infectious conjunctivitis.

Acute conjunctivitis: truth and misconceptions

OBJECTIVE

Acute conjunctivitis is an extremely common condition and can be associated with significant morbidity and economic burden. Despite this, considerable controversy exists pertaining to the prevalence, diagnosis, management, and treatment of the condition. A panel of ophthalmology experts was assembled to review and discuss the current evidence based literature as it pertains to each of these persistent controversies.

METHODS AND SCOPE

An acute conjunctivitis round table symposium was convened at the American Academy of Ophthalmology meeting in Atlanta, November 2008. The expert panelists consisted of four academic ophthalmologists in the field of cornea and external disease, whose discussion was informed by an English language literature survey carried out on the PubMed database for the period of January 1972 to October 2008. A narrative summary was generated from the literature review and direct transcription of this event, from which this Review article was developed.

FINDINGS AND CONCLUSIONS

Considerable light has been shed on acute microbial conjunctivitis and especially those cases caused by adenovirus. Many of the myths that have perpetuated for years have been debunked by emerging evidence. The advent and the implementation of better diagnostic tools and anti-viral medications will help clinicians to improve their diagnostic accuracy, improve management and treatment decisions, and ultimately benefit patients while saving overall healthcare costs.

Cost effectiveness of a point-of-care test for adenoviral conjunctivitis

BACKGROUND

Conjunctivitis is a relatively common condition of the eye that can be caused by a number of different pathogens including bacteria and viruses. Clinical differentiation between adenoviral and bacterial conjunctivitis is difficult, often resulting in misdiagnosis and the provision of inappropriate treatment.

METHODS

A cost-effectiveness analysis was performed from a societal perspective using primary, secondary, published literature, and expert opinion data sources. The incremental costs and effects (cases of unnecessary antibiotic treatment avoided) for a rapid point-of-care test for adenoviral conjunctivitis (RPS Adeno Detector) were modeled.

RESULTS

Using base case values, the incremental cost of using no point-of-care test compared with the point-of-care test is $71.30 with 0.1786 cases of unnecessary antibiotic treatment. Extrapolating these costs to the entire U.S. population per annum, society could potentially save nearly $430 million currently spent on unnecessary medical care and avoid over 1 million cases of unnecessary antibiotic treatment. The no-point-of-care test strategy is both more costly and less effective; indicating that the point-of-care test strategy is the most cost-effective option. The results were robust to variation in key model parameters.

CONCLUSIONS

Through the use of a rapid point-of-care test for adenovirus, much of the cost to society caused by acute conjunctivitis can be avoided through more timely and accurate diagnosis.

Acute bacterial conjunctivitis

Acute bacterial conjunctivitis is the eye disease most commonly seen by general practitioners, and is estimated to represent approximately 1% of all consultations in primary care. This article gives a review of the epidemiology, aetiology, clinical picture, complications, differential diagnoses, in vitro examinations and therapy of acute bacterial conjunctivitis. Until now, topical antibacterial therapy has generally been preferred by both physicians and patients because this will usually shorten the course of the disease slightly and allow the early readmittance of children to their kindergarten or school. Recently, several reports from primary care have confirmed the well-known clinical experience that the disorder has an excellent prognosis with a high frequency of spontaneous remission. In accordance, an expectant attitude or delayed prescription policy are now frequently strongly recommended. However, these reports also emphasize the difficulty in making a correct clinical distinction between bacterial and viral conjunctivitis. The effect of a general non-prescription attitude on transmission rates of pathogens also remains to be clarified. This must be born in mind when deciding how these patients should be handled. The socioeconomic and medical pros and cons of different treatment policies are discussed, and a highly personal view on the optimal handling strategy for these patients is also presented.

Management strategies for acute infective conjunctivitis in primary care: a systematic review

A systematic review of the literature on all aspects of the management of acute infective conjunctivitis is undertaken. Acute infective conjunctivitis is a common presentation in primary healthcare. It is usually a mild condition and serious complications are rare. Clinical signs are a poor discriminator of bacterial and viral causes. Studies of treatment show that there is a high rate of clinical cure without any treatment (65% within 2-5 days). Treatment with topical antibiotics improves the rate of clinical recovery and this is more marked in the first 2-5 days after presentation (number needed to treat [NNT] = 6), but less by 6-10 days (NNT = 13). Studies comparing treatment with different antibiotics do not demonstrate that any one antibiotic is superior; the choice of antibiotic should be based on consideration of cost and bacterial resistance. The present practice of prescribing antibiotics to most cases is not necessary.

The prevalence of adenoviral conjunctivitis at the Wills Eye Hospital Emergency Room

OBJECTIVE

The aim of this study was to evaluate the prevalence of adenoviral conjunctivitis by analyzing data from a prospective clinical study of 50 consecutive patients presenting to the Wills Eye Hospital Emergency Room (WEH ER) with a clinical diagnosis of infectious conjunctivitis from July 2003 to October 2003.

METHODS

The polymerase chain reaction (PCR) was used to evaluate all cases of clinically diagnosed infectious conjunctivitis. Based on the laboratory findings, the prevalence of adenovirus was determined.

RESULTS

Of the 50 consecutive patients with acute infectious conjunctivitis, 31 patients were PCR positive for adenovirus.

CONCLUSIONS

The prevalence of adenoviral conjunctivitis was found by PCR to represent 62% of all patients presenting with a clinical diagnosis of infectious conjunctivitis from July 2003 to October 2003.

The RPS adeno detector for diagnosing adenoviral conjunctivitis

PURPOSE

To compare the sensitivity, specificity, and accuracy of the RPS Adeno Detector (Rapid Pathogen Screening Inc., South Williamsport, PA) against both viral cell culture with confirmatory immunofluorescence staining (CC-IFA) and the polymerase chain reaction (PCR) for diagnosing adenoviral conjunctivitis.

DESIGN

Prospective, nonrandomized, masked, multicenter clinical trial.

PARTICIPANTS

One hundred eighty-six consecutive patients from 5 clinical centers seeking treatment within 1 week of developing a red eye and thought to have acute conjunctivitis.

METHODS

The RPS Adeno Detector is a 10-minute in-office lateral flow immunoassay. Patients were tested with the RPS Adeno Detector, CC-IFA, and PCR to detect the presence of adenovirus.

MAIN OUTCOME MEASURES

The sensitivity, specificity, and accuracy of the RPS Adeno Detector were assessed for identifying cases of adenoviral conjunctivitis.

RESULTS

Compared with CC-IFA, the RPS Adeno Detector was 88% sensitive and 91% specific at detecting adenoviral conjunctivitis. Using PCR as a reference method, the sensitivity of the RPS Adeno Detector increased to 89% and the specificity increased to 94%. Compared with PCR, CC-IFA was found to be 91% as sensitive and 100% as specific.

CONCLUSIONS

The RPS Adeno Detector demonstrated sufficient sensitivity and specificity to be used in the physician's office for the detection of adenoviral conjunctivitis.

Evaluation of sampling technique and transport media for the diagnostics of adenoviral eye infections. Adenovirus sampling and transport

BACKGROUND

Human adenoviruses (HAdV) may cause pharyngoconjunctival fever, follicular conjunctivitis or epidemic keratoconjunctivitis (EKC). Especially, outbreaks of the latter may lead to severe economic losses when preventive measures are implemented too late. Thus, a safe sampling method, proper specimen transport conditions and a fast and sensitive diagnostic technique is mandatory.

METHODS

Two commercially available virus transport systems (VTS) were compared with two NaCl-moisturised sampling devices, one of which comprises Dacron-tipped plastic-shafted swabs and the other a cotton-tipped wood-shafted swab, available in most ophthalmologists' offices. Downstream methods for specific detection of HAdV included direct immunofluorescence assay (IFA) of conjunctival swabs, virus isolation by cell culture and quantitative real-time polymerase chain reaction (qPCR). Furthermore, the influence of application of local anaesthetics prior to swabbing on subsequent detection of HAdV was investigated.

RESULTS

Application of local anaesthetics had a positive influence on the amount of swabbed cells, thus increasing the chance of obtaining positive results by IFA. Neither isolation of HAdV by cell culture nor by qPCR was negatively influenced by this pretreatment. Surprisingly, both commercially available VTS performed significantly worse than the NaCl-moisturised swabs. This was shown with regard to virus recovery rates in cell culture as well as viral genome copy numbers in the qPCR.

CONCLUSIONS

Based on our results, the following recommendations are provided to improve sampling, transport and diagnostic techniques regarding conjunctival swabs for diagnosis of human adenovirus infection: (1) application of local anaesthetics, (2) NaCl-moisturised VTS for shipment of specimens, and (3) detection of HAdV by qPCR. The latter method proved to be superior to virus isolation by cell culture, including subsequent identification by IFA, because it is faster, more sensitive and allows simultaneous handling of a number of samples. Hence, countermeasures to prevent further virus spread in an outbreak situation can be implemented earlier, thus reducing the number of subsequent adenoviral infections.

Evidence for persistence of adenovirus in the tear film a decade following conjunctivitis

Chronic papillary conjunctivitis has been described following adenoviral conjunctivitis. It is unknown however, how long adenovirus is able to persist in the tear film and conjunctiva. To determine if adenovirus persists in the ocular surface following adenoviral conjunctivitis, 304 patients with a history of adenovirus conjunctivitis from whom an adenovirus had been isolated 10 years previously were sent a questionnaire regarding persistent or recurrent symptoms and were invited to attend. Patients were examined and samples of tears and conjunctival cells were collected from both eyes using tear film washes, filter paper, and swabs, the latter for virus isolation. Extracted DNA from the ocular samples was amplified using primers for herpes simplex virus (thymidine kinase) and adenovirus (hexon) genes. Adenovirus amplicons were sequenced and compared to original serotype. Thirty patients attended, 19 of whom had persistent papillary conjunctivitis. Evidence of adenovirus DNA was detected in 17 of 30 patients, 15 of whom also had evidence of a chronic papillary conjunctivitis. Adenovirus DNA was significantly associated with papillary conjunctivitis (P = 0.03). Adenovirus amplicons were successfully sequenced from six patients. Four patients harbored type 3 adenovirus, the same serotype with which they were infected originally 10 years previously. Two patients were infected originally with adenovirus serotype 3 but the current serotype was type 4. Infection of the ocular surface with adenovirus may predispose to the development of a persistent or recurrent conjunctivitis, the presence of which, appears to be associated with evidence of long term persistence of adenovirus DNA.

A comparison of methods for detecting adenovirus type 8 keratoconjunctivitis during a nosocomial outbreak in a Neonatal Intensive Care Unit

BACKGROUND

An outbreak of epidemic keratoconjunctivitis (EKC) due to adenovirus (Ad) type 8 and involving 14 members of the hospital staff and 33 neonates admitted to the Neonatal Intensive Care Unit of the local University Hospital occurred between September and December 2000 in Pavia, Italy. The outbreak was preceded by an outbreak of EKC within the community.

OBJECTIVE

To compare the performance of conventional virus isolation on cell cultures, direct detection of Ad antigens in conjunctival cells by a direct fluorescent assay (DFA) and Ad DNA detection in conjunctival swabs by polymerase chain reaction (PCR) for diagnosis of adenoviral conjunctivitis.

STUDY DESIGN

Of conjunctival swabs collected from 47 patients, all were tested by virus isolation, 43 by direct Ad antigen detection, and 37 by Ad DNA detection. Direct Ad antigen detection was carried out by DFA using a group-specific monoclonal antibody. Detection and subgrouping of Ad DNA by nested PCR was performed using two sets of primers complementary to hexon and fiber genes, respectively.

RESULTS

Ad was detected in 24/47 (51.1%), 21/43 (48.8%), and 23/37 (62.1%) samples by virus isolation, direct antigen detection and PCR, respectively. Overall, 30/47 (63.8%) samples were Ad-positive. Of 37 specimens tested in parallel by all three methods, Ad was detected by at least one of the three techniques in 26/37 (70.3%). All Ad isolates were identified as serotype 8 by neutralization, while all PCR-positive samples were identified as belonging to subgroup D. No other virus was isolated from any conjunctival swab. Time required for test completion was 9.6 (4-20) days for virus isolation, 1-2 h for DFA and 24 h for PCR.

CONCLUSIONS

DFA was a sensitive and rapid assay but results depend on the quality of sample and the expertise of the observer. PCR was the most sensitive assay, although it takes longer to perform and requires dedicated facilities; thus, it could be restricted to DFA-negative samples. Virus isolation is still useful from an epidemiological point of view.

Development and use of nested polymerase chain reaction (PCR) for the detection of adenovirus from conjunctivitis specimens

BACKGROUND

The standard virus isolation method for detecting adenovirus is time consuming and direct detection of viral antigens in smears has its limitations. Therefore a rapid and a reliable method to identify virus in clinical specimens is desirable.

OBJECTIVE

To develop and evaluate nested PCR as a tool for detecting adenovirus from conjunctival swabs of patients with acute conjunctivitis during an epidemic.

STUDY DESIGN

A total of 201 patients with acute conjunctivitis were seen between August and November 1996. Conjunctival swabs from the most recently affected eyes were collected from 20 random patients and processed for antigen detection in direct smears, for adenovirus, enterovirus (EV70) and coxsackievirus A24 variant and adenovirus isolation by culture. Nested PCR was performed using oligonucleotides to amplify 1004 basepair (bp) and 956 bp fragments of DNA coding for adenovirus hexon protein. The neutralisation test, to type the adenovirus, was done on four isolates selected at random.

RESULTS

The PCR could detect 0.0032 fg of adenovirus DNA (corresponding to 8.3 x 10(-3) adenovirus particles). The EV70 and coxsackievirus A24 antigens were not detected. The specimens were positive for adenovirus by all three techniques in seven patients: (a) by direct smear and PCR in 2; (b) by virus isolation and PCR in 2; and (c) by PCR alone in five patients. In one patient the direct smear alone was positive. The PCR required 3 days to detect the virus, antigen detection provided diagnosis the same day and virus isolation required 8-27 days. A total of four isolates selected at random were identified as serotype 7a.

CONCLUSION

The nested PCR is a reliable and rapid technique for detection of adenovirus from conjunctival swabs. The adenovirus serotype 7a was the likely causative agent of this epidemic conjunctivitis.

The use of polymerase chain reaction for the detection of chlamydial keratoconjunctivitis

Ocular swabs from 30 consecutive patients with follicular conjunctivitis were screened for Chlamydia trachomatis, herpes simplex virus, and adenovirus by a variety of laboratory techniques. For the detection of C. trachomatis, we compared two polymerase chain reaction methods, McCoy cell culture isolation, and the direct fluorescein-conjugated monoclonal antibody test. Four of 30 patients tested positive for C. trachomatis by using both conventional and biotinylated polymerase chain reaction methods. Two of the four patients were also McCoy cell culture-positive for C. trachomatis and one of four patients tested positive by using a fluorescein-conjugated chlamydial monoclonal antibody test. All four patients responded to oral antibiotic treatment. On follow-up testing, all four patients were polymerase chain reaction-negative, McCoy cell culture-negative, and fluorescein-conjugated antibody test-negative for C. trachomatis. The polymerase chain reaction appears to be an equally specific and more sensitive method than McCoy cell culture or fluorescein-conjugated antibody testing for the detection of C. trachomatis from ocular specimens.

Subpicosecond equilibration of excitation energy in isolated photosystem II reaction centers

Photosystem II reaction centers have been studied by femtosecond transient absorption spectroscopy. We demonstrate that it is possible to achieve good photoselectivity between the primary electron donor P680 and the majority of the accessory chlorins. Energy transfer can be observed in both directions between P680 and these accessory chlorins depending on which is initially excited. After excitation of either P680 or the other chlorins, the excitation energy is observed to equilibrate between the majority of these pigments at a rate of 100 +/- 50 fs-1. This energy-transfer equilibration takes place before any electron-transfer reactions and must therefore be taken into account in studies of primary electron-transfer reactions in photosystem II. We also show further evidence that the initially excited P680 excited singlet state is delocalized over at least two chlorins and that this delocalization lasts for at least 200 fs.

Simulations of the temperature dependence of energy transfer in the PSI core antenna

In order to understand the organization of the PSI core antenna and to interpret results obtained from studies of the temperature and wavelength dependence of energy transfer and trapping in the PSI particles, we have constructed a model for PSI in which spectral heterogeneity is considered via a self-consistent approach based on Forster transport. The temperature dependence of the absorption and emission spectra of the individual Chl molecules in the protein matrix is calculated based on a model Hamiltonian which includes a phonon contribution. Time and wavelength resolved kinetics of PSI at different temperatures are investigated by means of two-dimensional lattice models. We conclude that wavelength-dependent fluorescence decay kinetics result only when two or more bottlenecks exist in the energy transfer and trapping process. A single trap or several pseudo-traps with spectrally identical environments do not lead to wavelength dependent decays. Simple funnel arrangements of the spectral types can be ruled out. At least one pigment with energy lower than the photochemical trap located close to the reaction center is required to produce the trends of the fluorescence lifetimes observed experimentally. The remainder of the core antenna is consistent with a random arrangement of spectral types.

The diagnosis and treatment of chlamydial conjunctivitis

Chlamydial conjunctivitis will usually go unrecognized and therefore untreated unless it is specifically considered. The possibility of chlamydial infection must be borne in mind in neonatal conjunctivitis, in acute conjunctivitis in sexually active adults, and in chronic follicular conjunctivitis. Chlamydial conjunctivitis is often indistinguishable from other forms of conjunctivitis on clinical grounds, and accurate diagnosis is based on laboratory tests. It seems that direct fluorescent antibody (DFA) cytology offers an attractive alternative to the more complicated and time-consuming tissue culture isolation method. Once diagnosed, chlamydial infection should be treated with the appropriate systemic antibiotics, and proper posttreatment follow-up is necessary to assess the efficacy of treatment.