Role of corneal biopsy in the management of infectious keratitis

Abstract

Purpose of reviewThe aim of this study was to review the existing literature and investigate the role of microbiologic culture and histopathologic examination of corneal biopsies in the management of infectious keratitis.Recent findingsCorneal biopsy continues to be a significantly useful tool in the diagnosis and tailored management of infectious keratitis. Several techniques can be employed for tissue collection, handling and processing to optimize diagnostic yield and maximize safety, including emerging femtosecond laser-assisted biopsy.SummaryCorneal opacities represent a significant cause of global blindness, and infectious keratitis is the most common cause. Organism identification in progressive infectious keratitis is essential for proper management. However, microbiological culture alone has a high rate of false-negative results. Records from the Bascom Palmer Eye Institute were retrospectively searched for patients between 1 January 2015, and 31 December 2019, who underwent corneal biopsy, therapeutic keratoplasty or endothelial graft removal for infectious keratitis and had specimens bisected and submitted for evaluation with both microbiologic culture and histopathologic examination. Detection of bacteria, fungus and mycobacteria was not statistically different between culture and histopathology. Microbiology and histopathology are complementary methods for the identification of causative microorganisms in corneal specimens with presumed infectious keratitis.

Transcriptional profiling specifies the pathogen-specific human host response to infectious keratitis

“…Emergency corneal transplantation is the only way to obtain large amounts of tissue from active corneal infection for histological and microbiological examination. Other complementary diagnostic techniques include corneal epithelial scraping, polymerase chain reaction (PCR) and in vivo confocal microscopy, albeit the latter with low sensitivity ( Hudson et al., 2022 ; Zemba et al., 2022 ).…”

Lasiodiplodia theobromae keratitis: A rare tropical fungal keratitis in a non-tropical climate

“…Biopsy of the sub-endothelial plaque also noted no microbes on culture and microscopy, most likely due to the samples being inflammatory infiltrate devoid of organisms. Possibly, a suture pass through the deep corneal infiltrate 14 together with next generation sequencing and metagenomics analysis 15 , 16 may have diagnosed the infection sooner. 14 , 15 , 16 …”

“…Possibly, a suture pass through the deep corneal infiltrate 14 together with next generation sequencing and metagenomics analysis 15 , 16 may have diagnosed the infection sooner. 14 , 15 , 16 …”

Application of Metagenomic Next-Generation Sequencing in the Diagnosis of Infectious Keratitis

“…After admission, a series of laboratory tests were performed, and the diagnosis was revised. These tests included (1) secretion culture (SC), identification, and drug sensitivity test: secretion of conjunctival sac, ulcer margin tissue, and aqueous humor were collected at the first visit, after admission, and during surgery; (2) corneal scraping microscopy (CS) performed using a potassium hydroxide wet tablet method [ 18 ]; (3) corneal laser confocal microscopy (CM) [ 19 ]: repeat testing was performed when fungal or parasitic infection was highly suspected and all other tests were negative; (4) pathological section (PS) [ 20 ]: lesion cornea was examined using routine hematoxylin-eosin (HE) and periodic acid-schiff (PAS) staining using OCUFACE biological microscopy. (5) mNGS [ 21 , 22 ]: samples were collected during lesion debridement or keratoplasty, including the aqueous humor, ulcerated marginal tissue, and cornea (avoid specimen contamination).…”