Draft Genome Sequence of Mycobacterium tuberculosis Strain SNMICRO 2047-20, Isolated from Intraocular Infection.

Here, we communicate the draft genome sequence of an ocular Mycobacterium tuberculosis strain (SNMICRO 2047-20) that was isolated from the vitreous fluid of a patient diagnosed with endophthalmitis. The genome sequence was 4,391,538 bp long with 3,898 protein-encoding genes and clustered to the East African-Indian lineage.

The Role of Ectodysplasin A on the Ocular Surface Homeostasis.

Ectodysplasin A (EDA), a ligand of the TNF family, plays an important role in maintaining the homeostasis of the ocular surface. EDA is necessary for the development of the meibomian gland, the lacrimal gland, as well as the proliferation and barrier function of the corneal epithelium. The mutation of EDA can induce the destruction of the ocular surface resulting in keratopathy, abnormality of the meibomian gland and maturation of the lacrimal gland. Experimental animal studies showed that a prenatal ultrasound-guided intra-amniotic injection or postnatal intravenous administration of soluble recombinant EDA protein can efficiently prevent the development of ocular surface abnormalities in EDA mutant animals. Furthermore, local application of EDA could restore the damaged ocular surface to some extent. Hence, a recombinant EDA-based therapy may serve as a novel paradigm to treat ocular surface disorders, such as meibomian gland dysfunction and corneal epithelium abnormalities.

Microbiological profile of canaliculitis and their antibiotic susceptibility patterns: A 11-year review at a referral eye care centre.

PURPOSE: To analyze the microbiological profile and in vitro antibiotic susceptibility patterns of bacterial isolates in canaliculitis, an infection of the lacrimal drainage system of the eye. METHODS: The laboratory records of patients presenting with canaliculitis from whom specimens were obtained for microbiological investigations at our tertiary eye care centre in South India from January 2010 to December 2020, were reviewed. RESULTS: A total of 130 canalicular pus samples were collected from 112 patients and submitted for microbiological studies during the study period. A total of 183 micro-organisms were isolated from 115 culture-positive specimens. The micro-organisms isolated were predominantly aerobic Gram-positive bacteria (83.44%), with Coagulase-negative Staphylococci (CoNS/Other Staphylococcus spp) (31.69%), Corynebacterium spp (15.3%), Staphylococcus aureus (9.84%) and Viridans Streptococci (9.84%) accounting for a majority of the isolates. Actinomycesspp (6.56%) was the most common anaerobic bacterium isolated. Our study revealed several bacteria not previously associated with canaliculitis namely Ottowia spp, Elizabethkingiameningoseptica, Aeromonassalmonicida, Capnocytophagaochracea and Campylobacter gracilis. Polymicrobial aetiology was observed in 39.13% of culture-positive samples. Analysis of antibiotic susceptibility patterns of the isolates revealed a high proportion of Gram-positive bacteria susceptible to chloramphenicol (90.16%) compared to fluoroquinolones including ciprofloxacin (74.42%), norfloxacin (64.15%) and gatifloxacin (60.49%). CONCLUSION: This study represents the largest series of canaliculitis reporting the microbiological profile and antibiotic susceptibilities of the isolated micro-organisms, till date. Gram-positive bacteria accounted for a majority of isolates, predominated by Staphylococcus spp. The increasing resistance of Gram-positive bacteria to fluoroquinolones warrants antibiotic treatment in canaliculitis is based on in vitro antimicrobial susceptibility patterns.

An Update on the Laboratory Diagnosis of Neuromyelitis Optica Spectrum Disorders.

Neuromyelitis optica spectrum disorder (NMOSD) is an autoimmune disorder of the central nervous system that is specifically associated with demyelination of spinal cord and optic nerves. The discovery of specific autoantibody markers such as aquaporin-4 IgG and myelin oligodendrocyte glycoprotein IgG has led to several methodologies being developed and validated. There have been numerous investigations of the clinical and radiological presentations used in the clinical diagnosis of NMOSD. However, although various laboratory diagnostic techniques have been standardized and validated, a gold-standard test has yet to be finalized due to uncertain sensitivities and specificities of the methodologies. For this review, the literature was surveyed to compile the standardized laboratory techniques utilized for the differential diagnosis of NMOSD. Enzyme-linked immunosorbent assays enable screening of NMOSD, but they are considered less sensitive than cell-based assays (CBAs), which were found to be highly sensitive and specific. However, CBAs are laborious and prone to batch variations in their results, since the expression levels of protein need to be maintained and monitored meticulously. Standardizing point-of-care devices and peptide-based assays would make it possible to improve the turnaround time and accessibility of the test, especially in resource-poor settings.

Therapeutic Effect of Corneal Crosslinking on Fungal Keratitis: Efficacy of Corneal Collagen Crosslinking as an Adjuvant Therapy for Fungal Keratitis in a Tertiary Eye Hospital in South India.

PURPOSE: To evaluate the efficacy of CXL in treating fungal keratitis as an adjuvant therapy. METHODS: Detailed clinical examination microbiological investigation was performed. Twenty fungal keratitis patients were recruited and randomized into two groups: group 1 (n= 11, standard antifungal), group 2 (n=9, corneal collagen crosslinking with standard antifungal). Corneal scraping and tear samples collected were subjected to real-time PCR targeting ITS, TLR analysis and cytokine analysis. RESULTS: The mean time for complete resolution of ulcer for group 2 was significantly shorter compared to group 1 and the final mean BCVA was better for group 2. Expression of IL-1ß, IL-8, IFN-γ significantly decreased immediately post CXL in group 2 patients. Significant downregulation of TLR 6, TLR-3, TLR-4 was observed 3-days post CXL compared to group 1 patients. CONCLUSION: Adjuvant effect of CXL was significant in treating fungal keratitis compared to standalone antifungal treatment.