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Concept: Conjunctivitis


Wearing contact lenses has been identified as a risk factor for the development of eye conditions such as giant papillary conjunctivitis and keratitis. We hypothesized that wearing contact lenses is associated with changes in the ocular microbiota. We compared the bacterial communities of the conjunctiva and skin under the eye from 58 subjects and analyzed samples from 20 subjects (9 lens wearers and 11 non-lens wearers) taken at 3 time points using a 16S rRNA gene-based sequencing technique (V4 region; Illumina MiSeq). We found that using anesthetic eye drops before sampling decreases the detected ocular microbiota diversity. Compared to those from non-lens wearers, dry conjunctival swabs from lens wearers had more variable and skin-like bacterial community structures (UniFrac;P value = <0.001), with higher abundances ofMethylobacterium,Lactobacillus,Acinetobacter, andPseudomonasand lower abundances ofHaemophilus,Streptococcus,Staphylococcus, andCorynebacterium(linear discriminant analysis [LDA] score = >3.0). The results indicate that wearing contact lenses alters the microbial structure of the ocular conjunctiva, making it more similar to that of the skin microbiota. Further research is needed to determine whether the microbiome structure provides less protection from ocular infections.

Concepts: Bacteria, Eye, Cornea, Contact lens, Contact lenses, Keratitis, Conjunctiva, Conjunctivitis


OBJECTIVE: To present a novel, minimally invasive technique for everted third eyelid cartilage correction in dogs that employs the use of low-energy cautery to remodel the cartilage. PROCEDURES: Twelve eyes of ten dogs had cautery performed under general anesthesia to correct everted third eyelid cartilage. The tip of a handheld cautery unit or an electrocautery handpiece was applied to the bulbar conjunctival surface of the third eyelid at the central location of cartilage convexity and treated to effect. This resulted in gradual conjunctival contraction and cartilage softening that remodeled the third eyelid to return to a more normal, physiologic position. When the tips of the cartilage bar were also curled, cautery was briefly applied to the convex surface to straighten the cartilage in a similar manner. RESULTS: Blanching of the conjunctiva at the site of treatment occurred. Char was sometimes present and was gently removed with a scalpel blade to improve postoperative patient comfort. Mild conjunctival hyperemia was noted in a few patients for 1-2 days after surgery, but there were no signs of discomfort or eyelid swelling. All dogs had good results in terms of cartilage correction with no recurrence; however, one of the Great Danes that had concurrent third eyelid gland prolapse required gland replacement surgery. CONCLUSIONS: Thermal cautery is a simple, inexpensive means of correcting third eyelid cartilage eversion in dogs with a high rate of success that preserves normal tissue while restoring function.

Concepts: Surgery, Eye, Anesthesia, Conjunctiva, Eyelid, Lacrimal nerve, Conjunctivitis, Scalpel


Antibiotics are seldom necessary to treat acute conjunctivitis. We assessed how frequently patients with newly diagnosed acute conjunctivitis fill prescriptions for topical antibiotics and factors associated with antibiotic prescription fills.

Concepts: Medical terms, United States, Greek loanwords, Antiviral drug, United Kingdom, Antibiotic, Topical, Conjunctivitis


Ophthalmia neonatorum, also called neonatal conjunctivitis, acquired during delivery can occur in the first 28 days of life. Commonly caused by the bacterial pathogen Neisseria gonorrhoeae, infection can lead to corneal scarring, perforation of the eye, and blindness. One approach that can be taken to prevent the disease is the use of an ophthalmic prophylaxis, which kills the bacteria on the surface of the eye shortly after birth. Current prophylaxes are based on antibiotic ointments. However, N. gonorrhoeae is resistant to many antibiotics and alternative treatments must be developed before the condition becomes untreatable. This study focused on developing a fatty acid-based prophylaxis. For this, 37 fatty acids or fatty acid derivatives were screened in vitro for fast antigonococcal activity. Seven candidates were identified as bactericidal at 1 mM. These seven were subjected to irritation testing using three separate methods: the bovine corneal opacity and permeability (BCOP) test; the hen’s egg test-chorioallantoic membrane (HET-CAM); and the red blood cell (RBC) lysis assay. The candidates were also tested in artificial tear fluid to determine whether they were effective in this environment. Four of the candidates remained effective. Among these, two lead candidates, monocaprin and myristoleic acid, displayed the best potential as active compounds in the development of a fatty acid-based prophylaxis for prevention of ophthalmia neonatorum.

Concepts: Bacteria, Fatty acid, Fatty acids, Antibiotic resistance, Ophthalmology, Penicillin, Conjunctivitis, Butyric acid


Trachoma is a conjunctiva scarring disease, which is the leading infectious cause of blindness worldwide. Yet, the molecular mechanisms underlying progressive fibrosis in trachoma are unknown. To investigate the contribution of local resident fibroblasts to disease progression, we isolated conjunctival fibroblasts from patients with scarring trachoma and matching control individuals, and compared their gene expression profiles and functional properties in vitro. We show that scarring trachoma fibroblasts substantially differ from control counterparts, displaying pro-fibrotic and pro-inflammatory features matched by an altered gene expression profile. This pro-inflammatory signature was exemplified by increased IL-6 expression and secretion, and a stronger response to macrophage-mediated stimulation of contraction. We further demonstrate that scarring trachoma fibroblasts can promote Akt phosphorylation in macrophages in an IL-6 -dependent manner. Overall this work has uncovered a distinctive molecular fingerprint for scarring trachoma fibroblasts, and identified IL-6- as a potential contributor to the chronic conjunctival fibrosis, mediating reciprocal pro-fibrotic/pro-inflammatory interactions between macrophages and fibroblasts.

Concepts: DNA, Gene, Gene expression, Cell, Molecular biology, Fibrosis, Feedback, Conjunctivitis


Parents of children who presented for a pediatrics appointment responded to a clinical vignette that described a child with symptoms consistent with acute viral conjunctivitis. In a 2 × 2 randomized survey design, the physician in the vignette either used the term “pink eye” or “eye infection” to describe the symptoms, and either told parents that antibiotics are likely ineffective at treating the symptoms or did not discuss effectiveness. When the symptoms were referred to as “pink eye,” parents remained interested in antibiotics, despite being informed about their ineffectiveness. By contrast, when the symptoms were referred to as an “eye infection,” information about antibiotic ineffectiveness significantly reduced interest, Mdiff = 1.63, P < .001. Parents who received the "pink eye" label also thought that the symptoms were more contagious and were less likely to believe that their child could go to child care, compared with parents who received the "eye infection" label, Mdiff = 0.37, P = .38.

Concepts: Medicine, Antiviral drug, Ophthalmology, Conjunctivitis, Common cold


Ocular allergy represents one of the most common conditions encountered by allergists and ophthalmologists. Allergic conjunctivitis is often underdiagnosed and consequently undertreated. Basic and clinical research has provided a better understanding of the cells, mediators, and immunologic events, which occur in ocular allergy. New pharmacological agents have improved the efficacy and safety of ocular allergy treatment. An understanding of the immunologic mechanisms, clinical features, differential diagnosis, and treatment of ocular allergy may be useful to all specialists who deal with these patients. The purpose of this review is to systematically review literature underlining all the forms classified as ocular allergy: seasonal allergic conjunctivitis, perennial allergic conjunctivitis, vernal keratoconjunctivitis, atopic keratocongiuntivitis, contact allergy, and giant papillary conjunctivitis.

Concepts: Medicine, Asthma, Hypersensitivity, Allergy, Mast cell, Ophthalmology, Conjunctivitis, Allergic conjunctivitis


Ophthalmic herpes simplex viral keratitis (HSVK) is responsible for a range of ocular manifestations from superficial epithelial disease to stromal keratitis and endotheliitis. The Herpetic Eye Disease Study (HEDS) has guided the management of herpetic eye disease for almost twenty years, but newer medications such as valacyclovir are now available and are considered to have better bioavailability than acyclovir. In this review, we examine the existing evidence on the pathogenesis of different HSVK disease modalities and the role of oral and topically administered antiviral drugs in the treatment of herpes simplex viral keratitis.

Concepts: Virus, Antiviral drug, Herpes simplex, Antibiotic, Antivirals, Keratitis, Conjunctivitis, Valaciclovir


Ebola hemorrhagic fever is a deadly disease caused by several species of ebolavirus. The current outbreak of 2014 is unique in that it has affected a greater number of people than ever before. It also has an unusual geographic distribution. Nonspecific findings such as fever and generalized weakness have traditionally been very common early in the acute phase. Ophthalmic manifestations have also been reported in significant numbers. Conjunctival injection has been identified in both the acute and late phases. Subconjunctival hemorrhage and excessive lacrimation have also been reported. Various forms of uveitis have been associated with the convalescent phase of the disease. When identified in conjunction with other signs such as fever, acute findings such as conjunctivitis may contribute to the diagnosis of Ebola hemorrhagic fever. Ideally, serologic testing should be performed prior to isolation and treatment of these individuals. Considering the prevalence of the current outbreak and the threat of transcontinental spread, ophthalmic health professionals need to be aware of the ocular manifestations of Ebola hemorrhagic fever as well as the associated signs and symptoms in order to prevent further spread.

Concepts: Ophthalmology, Conjunctiva, Conjunctivitis, Ebola, Marburg virus, Viral hemorrhagic fever, Incubation period, Subconjunctival hemorrhage


Olopatadine is an antihistamine and mast cell stabilizer used for treating allergic conjunctivitis. Olopatadine 0.7% has been recently approved for daily dosing in the US, which supersedes the previously approved 0.2% strength. The objective of this analysis was to characterize patients who have better itching relief at 24 h when taking olopatadine 0.7% treatment instead of olopatadine 0.2% (in terms of proportions of responses) and relate this to the severity of baseline itching as an indirect metric of a patient’s sensitivity to antihistamines. A differential odds model was developed using data from two conjunctival allergen challenge (CAC) studies to characterize individual-level and population-level response to ocular itching following olopatadine treatment and the data was analyzed retrospectively. This modeling analysis was designed to predict 24 h ocular itching scores and to quantify the differences in 24 h itching relief following treatment with olopatadine 0.2% versus 0.7% in patients with moderate-to-high baseline itching. A one-compartment kinetic-pharmacodynamic Emax model was used to determine the effect of olopatadine. Impact of baseline itching severity, vehicle effect and the drug effect on the overall itching scores post-treatment were explicitly incorporated in the model. The model quantified trends observed in the clinical data with regards to both mean scores and the proportions of patients responding to olopatadine treatment. The model predicts a higher proportion of patients in the olopatadine 0.7% versus 0.2% group will experience relief within 24 h. This prediction was confirmed with retrospective clinical data analysis. The number of allergy patients relieved with olopatadine 0.7% increased with higher baseline itching severity scores, when compared to olopatadine 0.2%.

Concepts: Scientific method, Asthma, Effectiveness, Allergy, Mast cell, Histamine, Conjunctivitis, Allergic conjunctivitis