Diagnostic armamentarium of infectious keratitis: A comprehensive review

Abstract

Infectious keratitis (IK) represents the leading cause of corneal blindness worldwide, particularly in developing countries. A good outcome of IK is contingent upon timely and accurate diagnosis followed by appropriate interventions. Currently, IK is primarily diagnosed on clinical grounds supplemented by microbiological investigations such as microscopic examination with stains, and culture and sensitivity testing. Although this is the most widely accepted practice adopted in most regions, such an approach is challenged by several factors, including indistinguishable clinical features shared among different causative organisms, polymicrobial infection, long diagnostic turnaround time, and variably low culture positivity rate. In this review, we aim to provide a comprehensive overview of the current diagnostic armamentarium of IK, encompassing conventional microbiological investigations, molecular diagnostics (including polymerase chain reaction and mass spectrometry), and imaging modalities (including anterior segment optical coherence tomography and in vivo confocal microscopy). We also highlight the potential roles of emerging technologies such as next-generation sequencing, artificial intelligence-assisted platforms. and tele-medicine in shaping the future diagnostic landscape of IK.

Alginate-Based Composites for Corneal Regeneration: The Optimization of a Biomaterial to Overcome Its Limits

“…In accordance with the last global report on vision, presented by the World Health Organization, over 2.2 billion people live with a vision impairment; among them, 123.7 million people are affected by unaddressed refractive errors and 4.2 million are suffering from corneal opacities [17]. Keratitis [18], corneal dystrophies [19], wounds [20],…”

“…In accordance with the last global report on vision, presented by the World Health Organization, over 2.2 billion people live with a vision impairment; among them, 123.7 million people are affected by unaddressed refractive errors and 4.2 million are suffering from corneal opacities [ 17 ]. Keratitis [ 18 ], corneal dystrophies [ 19 ], wounds [ 20 ], neovascularization [ 21 ] or structural modifications in thickness [ 22 ] are just some examples among the best-known diseases affecting the cornea. When irreversible damage involves the cornea, a loss of corneal transparency occurs, leading to severe vision impairment or blindness.…”

A Review on Pathogens and Necessary Diagnostic Work for Bleb-Related Infections (BRIs)

“…The advantages of PCR in aqueous and vitreous samples include the delivery of fast results (within 90 min), as well as a much higher specificity and sensitivity compared to standard microbiologic culture [ 40 , 53 , 54 ]. These features make PCR a helpful tool, especially in cases where traditional cultures take weeks to provide results, such as in slow-growing bacteria such as mycobacteria, or in organisms that are difficult to culture, such as Microsporidia , Propionibacterium acnes and Toxoplasma gondii , in all of which the earlier initiation of treatment could provide a better visual outcomes [ 40 , 55 ].…”

Diagnostic Performance of Deep Learning in Infectious Keratitis: A Systematic Review and Meta-Analysis Protocol

“…in vivo confocal microscopy (IVCM)]. [15][16][17] However, these approaches have multiple challenges, including the need for clinical expertise and equipment, low microbiological culture yield, long turnaround time, poorly differentiated clinical features, and polymicrobial infections. 7,15,18,19 Moreover, access to such microbiological and imaging 6 investigations is not available in many ophthalmic units in LMICs, leading to a reliance of empirical treatment.…”

“…[15][16][17] However, these approaches have multiple challenges, including the need for clinical expertise and equipment, low microbiological culture yield, long turnaround time, poorly differentiated clinical features, and polymicrobial infections. 7,15,18,19 Moreover, access to such microbiological and imaging 6 investigations is not available in many ophthalmic units in LMICs, leading to a reliance of empirical treatment. This can lead to a misdiagnosis when based on clinical features alone and the use of incorrect antimicrobial therapy (e.g., fungal keratitis being treated only with anti-bacterial agents).…”