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An Approach to Visual Loss in a Child
Published in Vivek Lal, A Clinical Approach to Neuro-Ophthalmic Disorders, 2023
Muhammad Hassaan Ali, Stacy L. Pineles
Refractive errors are common in infants but are only treated with spectacles if they are greater than 3–4 D or are causing strabismus or asthenopic symptoms. Young patients may also present with complaints of severe itching and redness in the eyes. Consider vernal keratoconjunctivitis in such cases and check for signs of keratoconus which develops as a consequence of repeated rubbing of eyes.
Ocular surface as mucosal immune site
Published in Phillip D. Smith, Richard S. Blumberg, Thomas T. MacDonald, Principles of Mucosal Immunology, 2020
Rachel R. Caspi, Anthony St. Leger
Most types of allergic conjunctivitis are fairly benign, if unpleasant. However, there are exceptions. Vernal keratoconjunctivitis is a relatively rare but serious allergic response that can leave permanent scarring and visual deficit. It occurs most often in spring (vernal) in young boys around 8 years of age and usually resolves spontaneously at puberty, indicating a hormonal influence. It is characterized by conjunctival giant papillae, hyperemia, and frequent involvement of the cornea. Although allergic mechanisms, including presence of typical TH2-type immunity and IgE, are well documented in vernal keratoconjunctivitis, up to 50% of patients do not have a family or medical history of allergic diseases and do not show IgE sensitization, suggesting that this disease is not solely IgE mediated. Recent studies have also pointed out the role of resident conjunctival nonlymphoid cells in the pathogenetic processes of vernal keratoconjunctivitis. Thus, the pathogenesis of the condition is likely to be multifactorial and complex, involving not only the ocular mucosal immune system but also, similarly to Sjögren's syndrome, the nervous and endocrine systems.
Ophthalmology
Published in Stephan Strobel, Lewis Spitz, Stephen D. Marks, Great Ormond Street Handbook of Paediatrics, 2019
Although seasonal allergic conjunctivitis is extremely common, vernal keratoconjunctivitis with corneal involvement is much less common. It is a severe allergic form of eye disease. It presents with mucoid discharge and lumps on the superior tarsal conjunctiva (papillae) (Fig. 7.22), which cause trauma to the superior half of the cornea leading to corneal epithelial erosions, shield ulcers (5% of patients) and corneal vascularisation (micropannus).
Presentation, diagnosis, and the role of subcutaneous and sublingual immunotherapy in the management of ocular allergy
Published in Clinical and Experimental Optometry, 2021
Amruta Trivedi, Constance Katelaris
Vernal keratoconjunctivitis represents 0.5 per cent of allergic eye disease, affects mainly children and young adolescents, has a male predominance, and occurs more commonly in warm climates.28,29 Vernal keratoconjunctivitis is characterised by the presence of corneal epithelial stromal lesions, as well as conjunctival proliferative changes, with giant papillae in the upper conjunctiva, giving it a cobblestone appearance on the surface of the everted eyelid (Figure 2C). Additionally, patients can develop gelatinous eosinophilic and neutrophilic mounds (Trantas dots) (Figure 2D‐E). These changes cause intense itch, tearing, mucous discharge, ocular pain due to corneal involvement, severe photophobia, and intense foreign body sensation due to the irregularity of the conjunctival surface and copious mucous production.18 The massive eosinophilic infiltration and activation in the conjunctiva is responsible for corneal complications. Chronic eye rubbing contributes to keratoconus and other corneal ectasias, and corneal ulcers may form in severe cases.30 If left untreated, corneal involvement causes permanent scarring and visual impairment.
Density and Morphology of Corneal Epithelial Dendritic Cells are Different in Allergy
Published in Current Eye Research, 2020
Zahra Tajbakhsh, Isabelle Jalbert, Sailesh Kolanu, Fiona Stapleton, Blanka Golebiowski
A key finding is the presence of CEDC with a higher-grade morphology in the central and mid-peripheral cornea of the allergic group. This is in agreement with previous studies which qualitatively described corneal dendritic cell morphology in patients with severe vernal keratoconjunctivitis.6,7 Higher-grade cells may represent a more mature phenotype and indicate the activation of inflammation and immunity in the ocular surface of allergic participants.16,17 In the non-allergic participants, CEDC with long dendrites were not observed at either corneal location. An earlier study of CEDC in the normal human cornea found the corneal centre to be devoid of cells with long dendrites and observed the more mature morphology in the peripheral cornea only.18 These results are consistent with ex vivo studies in animals.19
Influence of gut microbiota on eye diseases: an overview
Published in Annals of Medicine, 2021
Pasquale Napolitano, Mariaelena Filippelli, Sergio Davinelli, Silvia Bartollino, Roberto dell’Omo, Ciro Costagliola
Several studies have suggested that osmolarity (OSM) alterations, seen in dry eye and blepharitis, could be related to gut microbiota dysregulation. In addition, they explored the bacteria found in Meibomian gland secretions in an effort to find a stronger relationship between microbial composition and MGD severity. Data collected by the authors were based on clinical signs, such as conjunctival injection, upper and lower tear meniscus height (TMH), tear breakup time (TBUT), corneal staining, lid margin, orifice, tear foam, and Meibomian gland assessment. According to the literature, the commensal microbiome changes with the severity of MGD. In particular, the abundance and complexity of the microbiome have increased. However, the low-mild pattern of MGD presented an increased number of bacterial species compared to the control, as Microbacteriaceae and Bacillus were missing. On the contrary, in mild MGD, the percentage of bacterial population was higher than that in the control, which indicated an altered microenvironment. One of the most representative samples detected in the severe MGD group was Corynebacterium, particularly C. macginleyi. In contrast, S. epidermidis was found in the normal controls. In conclusion, Bonini et al. found a relationship between vernal keratoconjunctivitis and probiotic eye drops [72]. In their study, they administered Lactobacillus acidophilus eye drops in patients with Vernal keratoconjunctivitis, prepared using freeze-dried inactivated L. acidophilus, four times a day in both eyes for one month after three days of washout. They demonstrated that a 4-week treatment relieved the signs and symptoms of vernal keratoconjunctivitis in the active phase. Thus, we can assert that many associations exist between the microbiota and ocular surface disease, and further studies are needed to characterise the precise mechanisms responsible for these associations.