Pathogenesis of microbial keratitis

Lakhundi, Sahreena; Siddiqui, Ruqaiyyah; Khan, Naveed Ahmed

doi:10.1016/j.micpath.2016.12.013

Cited by 181 publications

(162 citation statements)

References 190 publications

(206 reference statements)

Supporting

Mentioning

138

Contrasting

Unclassified

Order By: Relevance

“…Filamentous fungal keratitis caused by Fusarium or Aspergillus is more commonly associated with tropical climates and ocular trauma; however, keratitis caused by yeast-like fungi, Candida spp. , are more closely linked to temperate climates and pre-existing conditions like insufficient tear quality, defective eyelid function, diabetes mellitus, or immunosuppression (Lakhundi et al, 2017; Nivenius and Montan, 2015; Oude Lashof et al, 2011; Romano et al, 1976; Thomas and Kaliamurthy, 2013). …”

Section: Discussionmentioning

confidence: 99%

An Ocular Commensal Protects against Corneal Infection by Driving an Interleukin-17 Response from Mucosal γδ T Cells

et al. 2017

View full text Add to dashboard Cite

Summary Mucosal sites such as the intestine, oral cavity, nasopharynx, and vagina all have associated commensal flora. The surface of the eye is also a mucosal site, but proof of a living, resident ocular microbiome remains elusive. Here, we used a mouse model of ocular surface disease to reveal that commensals were present in the ocular mucosa and had functional immunological consequences. We isolated one such candidate commensal, Corynebacterium mastitidis and showed that this organism elicited a commensal-specific interleukin 17 response from γδ T cells in the ocular mucosa that was central to local immunity. The commensal-specfic response drove neutrophil recruitment and the release of antimicrobials into the tears, and protected the eye from pathogenic Candida albicans or Pseudomonas aeruginosa infection. Our findings provide direct evidence that a resident commensal microbiome exists on the ocular surface and identify the cellular mechanisms underlying its effects on ocular immune homeostasis and host defense.

show abstract

Section: Discussionmentioning

confidence: 99%

An Ocular Commensal Protects against Corneal Infection by Driving an Interleukin-17 Response from Mucosal γδ T Cells

et al. 2017

View full text Add to dashboard Cite

show abstract

“…The presence of inflammatory factors indicates both the presence of mechanical trauma and corneal wound healing response. Although healing of the corneal surface is known to be highly efficient, trauma leading to gaps in the surface breaches the ocular defence, allowing the entry of micro‐organisms and potential development of infections …”

Section: Use Of Contact Lensesmentioning

confidence: 99%

Disturbing the balance: effect of contact lens use on the ocular proteome and microbiome

Boost

Cho

Wang

2017

Clinical and Experimental Optometry

View full text Add to dashboard Cite

Contact lens wear is a popular, convenient and effective method for vision correction. In recent years, contact lens practice has expanded to include new paradigms, including orthokeratology; however, their use is not entirely without risk, as the incidence of infection has consistently been reported to be higher in contact lens wearers. The explanations for this increased susceptibility have largely focused on physical damage, especially to the cornea, due to a combination of hypoxia, mechanical trauma, deposits and solution cytotoxicity, as well as poor compliance with care routines leading to introduction of pathogens into the ocular environment. However, in recent years, with the increasing availability and reduced cost of molecular techniques, the ocular environment has received greater attention with in‐depth studies of proteins and other components. Numerous proteins were found to be present in the tears and their functions and interactions indicate that the tears are far more complex than formerly presumed. In addition, the concept of a sterile or limited microbial population on the ocular surface has been challenged by analysis of the microbiome. Ocular microbiome was not considered as one of the key sites for the Human Microbiome Project, as it was thought to be limited compared to other body sites. This was proven to be fallacious, as a wide variety of micro‐organisms were identified in the analyses of human tears. Thus, the ocular environment is now recognised to be more complicated and interference with this ecological balance may lead to adverse effects. The use of contact lenses clearly changes the situation at the ocular surface, which may result in consequences which disturb the balance in the healthy eye.

show abstract

“…Infection usually begins with epithelial defects in the setting of a weakened ocular defense system and proceeds to stromal invasion, necrosis, and corneal ulceration. [1] Ulcers can lead to visual impairment and may lead to corneal perforation and endophthalmitis. Outcomes of these patients depend on timely diagnosis and treatment with close follow-up.…”

Section: Introductionmentioning

confidence: 99%

“…[12][13][14][15][16] Acanthamoeba keratitis is rare but is typically associated with contact lens wear. [1] The purpose of this study was to characterize the etiologies of infectious keratitis presenting to a tertiary teaching hospital system in South Texas to better guide future treatment. We aimed to identify the microbial spectrum in this population and compare these data to reports from other parts of the country as well as around the world.…”

Section: Introductionmentioning

confidence: 99%

Etiology and Risk Factors for Infectious Keratitis in South Texas

Puig

Weiss

Salinas

et al. 2020

JOVR

View full text Add to dashboard Cite

Purpose: To determine the causative organisms and associated risk factors for infectious keratitis in South Texas. Methods: This retrospective study was performed at a tertiary teaching hospital system in South Texas. Medical records of all patients who presented with infectious keratitis from 2012 to 2018 were reviewed. Only patients with culture-proven bacterial, fungal, and Acanthamoeba keratitis were included. Results: In total, 182 eyes of 181 patients had culture-proven bacterial, fungal, or Acanthamoeba keratitis. The age of patients ranged from 3 to 93 years, with a mean of 48.3 ± 20.8 years. The most common etiologic agent was bacteria, with 173 bacterial cultures (95.1%) recovered, followed by 13 fungal cultures (7.1%), and 3 Acanthamoeba cultures (1.6%). Of the 218 bacterial isolates, coagulase-negative Staphylococcus was the most common (25.7%), followed by Pseudomonas aeruginosa (23.4%), Staphylococcus aureus (11.0%), and Moraxella (7.8%). Fusarium was the most common fungal isolate (46.2%). The most common risk factors for infectious keratitis included contact lens wear (32.4%), underlying corneal disease (17.6%), trauma (14.3%), and ocular surface disease (13.7%). Conclusions: Bacteria are the most common cause of infectious keratitis in this patient population, with coagulase-negative Staphylococcus and Pseudomonas as the most common isolates. The prevalence of culture-positive fungal keratitis is significantly lower than that of bacterial keratitis. Contact lens wear is the most common risk factor associated with infectious keratitis in South Texas.

show abstract

Pathogenesis of microbial keratitis

Cited by 181 publications

References 190 publications

An Ocular Commensal Protects against Corneal Infection by Driving an Interleukin-17 Response from Mucosal γδ T Cells

An Ocular Commensal Protects against Corneal Infection by Driving an Interleukin-17 Response from Mucosal γδ T Cells

Disturbing the balance: effect of contact lens use on the ocular proteome and microbiome

Etiology and Risk Factors for Infectious Keratitis in South Texas

Contact Info

Product

Resources

About