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Chihching Huang - One of the best experts on this subject based on the ideXlab platform.
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dual functional gelatin capped silver nanoparticles for antiBacterial and antiangiogenic treatment of Bacterial Keratitis
Journal of Colloid and Interface Science, 2019Co-Authors: Lijyuan Luo, Tzuyu Lin, Chunhsu Yao, Peiyin Kuo, Michiya Matsusaki, Scott G Harroun, Chihching Huang, Juiyang LaiAbstract:Abstract Staphylococcus aureus (S. aureus) is a leading cause of Keratitis worldwide and a significant threat to healthy vision. Pathological manifestations of Bacterial Keratitis (BK) caused by S. aureus involve stromal opacity, edema and neovascularization of an inflamed cornea, requiring immediate medical attention. Thus, S. aureus-induced Keratitis is a devastating ocular infection that can lead to blindness if effective and timely treatment is not initiated. In this study, we demonstrate gelatin-capped silver nanoparticles (G-Ag NPs) as anti-infective therapeutics for the treatment of S. aureus-induced Keratitis. G-Ag NPs were prepared by simple mixing of silver nitrate, maltose and gelatin. The gelatin molecules are capped in situ on the Ag NPs (∼14 nm). Compared to uncapped Ag NPs, the G-Ag NPs possess superior stability and antiBacterial activity against S. aureus. We further demonstrate that G-Ag NPs possess effective inhibition of the proliferation, migration and tube formation of human umbilical vein endothelial cells, as well as strong disturbance of the angiogenesis in chick chorioallantoic membrane and rabbit corneal neovascularization. Furthermore, intrastromal administration of highly biocompatible G-Ag NPs alleviates S. aureus-induced Bacterial Keratitis in rabbit eyes and Bacterial infection-induced corneal neovascularization. Our results demonstrate G-Ag NPs as a promising dual functional (antimicrobial and antiangiogenic) nanotherapeutic for preclinical treatment of eye-related microbial infections.
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super cationic carbon quantum dots synthesized from spermidine as an eye drop formulation for topical treatment of Bacterial Keratitis
ACS Nano, 2017Co-Authors: Hongjyuan Jian, Scott G Harroun, Rensiang Wu, Yujia Li, Chihching HuangAbstract:We have developed a one-step method to synthesize carbon quantum dots (CQDPAs) from biogenic polyamines (PAs) as an antiBacterial agent for topical treatment of Bacterial Keratitis (BK). CQDs synthesized by direct pyrolysis of spermidine (Spd) powder through a simple dry heating treatment exhibit a solubility and yield much higher than those from putrescine and spermine. We demonstrate that CQDs obtained from Spds (CQDSpds) possess effective antiBacterial activities against non-multidrug-resistant Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella enterica serovar Enteritidis bacteria and also against the multidrug-resistant bacteria, methicillin-resistant S. aureus. The minimal inhibitory concentration (MIC) of CQDSpds is ∼2500-fold lower than that of spermidine alone, demonstrating their strong antiBacterial capabilities. Investigation of the possible mechanisms behind the antiBacterial activities of the as-synthesized CQDSpds indicates that the super-cationic CQDSpds with s...
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super cationic carbon quantum dots synthesized from spermidine as an eye drop formulation for topical treatment of Bacterial Keratitis
ACS Nano, 2017Co-Authors: Hongjyuan Jian, Tzuyu Lin, Scott G Harroun, Chihching Huang, Juiyang Lai, Hanjia LinAbstract:We have developed a one-step method to synthesize carbon quantum dots (CQDPAs) from biogenic polyamines (PAs) as an antiBacterial agent for topical treatment of Bacterial Keratitis (BK). CQDs synthesized by direct pyrolysis of spermidine (Spd) powder through a simple dry heating treatment exhibit a solubility and yield much higher than those from putrescine and spermine. We demonstrate that CQDs obtained from Spds (CQDSpds) possess effective antiBacterial activities against non-multidrug-resistant Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella enterica serovar Enteritidis bacteria and also against the multidrug-resistant bacteria, methicillin-resistant S. aureus. The minimal inhibitory concentration (MIC) of CQDSpds is ∼2500-fold lower than that of spermidine alone, demonstrating their strong antiBacterial capabilities. Investigation of the possible mechanisms behind the antiBacterial activities of the as-synthesized CQDSpds indicates that the super-cationic CQDSpds with s...
Juiyang Lai - One of the best experts on this subject based on the ideXlab platform.
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dual functional gelatin capped silver nanoparticles for antiBacterial and antiangiogenic treatment of Bacterial Keratitis
Journal of Colloid and Interface Science, 2019Co-Authors: Lijyuan Luo, Tzuyu Lin, Chunhsu Yao, Peiyin Kuo, Michiya Matsusaki, Scott G Harroun, Chihching Huang, Juiyang LaiAbstract:Abstract Staphylococcus aureus (S. aureus) is a leading cause of Keratitis worldwide and a significant threat to healthy vision. Pathological manifestations of Bacterial Keratitis (BK) caused by S. aureus involve stromal opacity, edema and neovascularization of an inflamed cornea, requiring immediate medical attention. Thus, S. aureus-induced Keratitis is a devastating ocular infection that can lead to blindness if effective and timely treatment is not initiated. In this study, we demonstrate gelatin-capped silver nanoparticles (G-Ag NPs) as anti-infective therapeutics for the treatment of S. aureus-induced Keratitis. G-Ag NPs were prepared by simple mixing of silver nitrate, maltose and gelatin. The gelatin molecules are capped in situ on the Ag NPs (∼14 nm). Compared to uncapped Ag NPs, the G-Ag NPs possess superior stability and antiBacterial activity against S. aureus. We further demonstrate that G-Ag NPs possess effective inhibition of the proliferation, migration and tube formation of human umbilical vein endothelial cells, as well as strong disturbance of the angiogenesis in chick chorioallantoic membrane and rabbit corneal neovascularization. Furthermore, intrastromal administration of highly biocompatible G-Ag NPs alleviates S. aureus-induced Bacterial Keratitis in rabbit eyes and Bacterial infection-induced corneal neovascularization. Our results demonstrate G-Ag NPs as a promising dual functional (antimicrobial and antiangiogenic) nanotherapeutic for preclinical treatment of eye-related microbial infections.
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super cationic carbon quantum dots synthesized from spermidine as an eye drop formulation for topical treatment of Bacterial Keratitis
ACS Nano, 2017Co-Authors: Hongjyuan Jian, Tzuyu Lin, Scott G Harroun, Chihching Huang, Juiyang Lai, Hanjia LinAbstract:We have developed a one-step method to synthesize carbon quantum dots (CQDPAs) from biogenic polyamines (PAs) as an antiBacterial agent for topical treatment of Bacterial Keratitis (BK). CQDs synthesized by direct pyrolysis of spermidine (Spd) powder through a simple dry heating treatment exhibit a solubility and yield much higher than those from putrescine and spermine. We demonstrate that CQDs obtained from Spds (CQDSpds) possess effective antiBacterial activities against non-multidrug-resistant Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, and Salmonella enterica serovar Enteritidis bacteria and also against the multidrug-resistant bacteria, methicillin-resistant S. aureus. The minimal inhibitory concentration (MIC) of CQDSpds is ∼2500-fold lower than that of spermidine alone, demonstrating their strong antiBacterial capabilities. Investigation of the possible mechanisms behind the antiBacterial activities of the as-synthesized CQDSpds indicates that the super-cationic CQDSpds with s...
Muthiah Srinivasan - One of the best experts on this subject based on the ideXlab platform.
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trends in antibiotic resistance in Bacterial Keratitis isolates from south india
British Journal of Ophthalmology, 2017Co-Authors: Prajna Lalitha, Jeena Mascarenhas, Muthiah Srinivasan, Namperumalsamy Venkatesh Prajna, Travis C Porco, Geetha Manoharan, Rajaram Karpagam, Manoranjan Das, Thomas M LietmanAbstract:Aims To report trends in antibiotic resistance in cases of Bacterial Keratitis from a large eye hospital in South India. Methods In this retrospective cross-sectional study, the microbiology laboratory records of patients with infectious Keratitis diagnosed at an eye hospital in South India from 2002 to 2013 were reviewed to determine the proportion with antibiotic non-susceptibility. Results 3685 Bacterial isolates had susceptibility testing performed over the 12-year period. The two most common organisms with resistance were Streptococcus pneumoniae (n=1204) and Pseudomonas aeruginosa (n=894). Antibiotic non-susceptibility was generally uncommon for these two organisms and no significant trends were detected over the course of the study. In contrast, Staphylococcus aureus (N=211) isolates demonstrated a significant increase in fluoroquinolone non-susceptibility over the 12-year study period. This coincided with a significant increase in methicillin-resistant S. aureus (MRSA) during the study period, though the increase in fluoroquinolone resistance was likewise seen in methicillin-sensitive S. aureus (MSSA). For example, ofloxacin resistance in MSSA increased from 11.1% in 2002 to 66.7% in 2013 (p=0.002). No trends were apparent for the aminoglycosides, cefazolin or vancomycin, for which in vitro non-susceptibility generally appeared to be low. Conclusion Resistance to antibiotics was generally stable for infectious Keratitis isolates from a large eye hospital in South India, except for S. aureus , which experienced a significant increase in fluoroquinolone resistance from 2002 to 2013. Fluoroquinolone antibiotics currently have poor in vitro activity against both MRSA and MSSA in South India and are therefore not the ideal therapy for Staphylococcal corneal ulcers.
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visual recovery in treated Bacterial Keratitis
Ophthalmology, 2014Co-Authors: Muthiah Srinivasan, Jeena Mascarenhas, Prajna Lalitha, Thomas M Lietman, Revathi Rajaraman, Meenakshi Ravindran, Kathryn J Ray, Michael E Zegans, Nisha R Acharya, Jeremy D KeenanAbstract:Bacterial Keratitis is a leading cause of visual impairment worldwide. However, the natural history of treated Bacterial Keratitis has not been well characterized. We performed a secondary analysis of the Steroids for Corneal Ulcers Trial (SCUT; clinicaltrials.gov #NCT00324168) to better characterize the rate of visual acuity improvement after successful antimicrobial treatment.
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early addition of topical corticosteroids in the treatment of Bacterial Keratitis
JAMA Ophthalmology, 2014Co-Authors: Kathryn J Ray, Jeena Mascarenhas, Muthiah Srinivasan, Catherine E Oldenburg, Revathi Rajaraman, Meenakshi Ravindran, Michael E Zegans, David V Glidden, Catherine Q Sun, Stephen D McleodAbstract:Importance Scarring from Bacterial Keratitis remains a leading cause of visual loss. Objective To determine whether topical corticosteroids are beneficial as an adjunctive therapy for Bacterial Keratitis if given early in the course of infection. Design, Setting, and Participants The Steroids for Corneal Ulcers Trial (SCUT) was a randomized, double-masked, placebo-controlled trial that overall found no effect of adding topical corticosteroids to topical moxifloxacin hydrochloride in Bacterial Keratitis. Here, we assess the timing of administration of corticosteroids in a subgroup analysis of the SCUT. We define earlier administration of corticosteroids (vs placebo) as addition after 2 to 3 days of topical antibiotics and later as addition after 4 or more days of topical antibiotics. Main Outcomes and Measures We assess the effect of topical corticosteroids (vs placebo) on 3-month best spectacle-corrected visual acuity in patients who received corticosteroids or placebo earlier vs later. Further analyses were performed for subgroups of patients with non- Nocardia Keratitis and those with no topical antibiotic use before enrollment. Results Patients treated with topical corticosteroids as adjunctive therapy within 2 to 3 days of antibiotic therapy had approximately 1-line better visual acuity at 3 months than did those given placebo (–0.11 logMAR; 95% CI, –0.20 to –0.02 logMAR; P = .01). In patients who had 4 or more days of antibiotic therapy before corticosteroid treatment, the effect was not significant; patients given corticosteroids had 1-line worse visual acuity at 3 months compared with those in the placebo group (0.10 logMAR; 95% CI, –0.02 to 0.23 logMAR; P = .14). Patients with non- Nocardia Keratitis and those having no topical antibiotic use before the SCUT enrollment showed significant improvement in best spectacle-corrected visual acuity at 3 months if corticosteroids were administered earlier rather than later. Conclusions and Relevance There may be a benefit with adjunctive topical corticosteroids if application occurs earlier in the course of Bacterial corneal ulcers.
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visual outcomes in treated Bacterial Keratitis four years of prospective follow up
Investigative Ophthalmology & Visual Science, 2014Co-Authors: Scott M Mcclintic, Jeena Mascarenhas, Prajna Lalitha, Muthiah Srinivasan, Catherine E Oldenburg, Revathi Rajaraman, Kathryn J Ray, Namperumalsamy Venkatesh Prajna, Kieran S Obrien, Nisha R AcharyaAbstract:Purpose. We described the change in visual acuity experienced by eyes successfully treated for Bacterial Keratitis.
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acanthamoeba fungal and Bacterial Keratitis a comparison of risk factors and clinical features
American Journal of Ophthalmology, 2014Co-Authors: Jeena Mascarenhas, Prajna Lalitha, Venkatesh N Prajna, Muthiah Srinivasan, Sean S Dsilva, Catherine E Oldenburg, Durga S Borkar, Elizabeth Esterberg, Thomas M Lietman, Jeremy D KeenanAbstract:Purpose To determine risk factors and clinical signs that may differentiate between Bacterial, fungal, and acanthamoeba Keratitis among patients presenting with presumed infectious Keratitis. Design Hospital-based cross-sectional study. Methods We examined the medical records of 115 patients with laboratory-proven Bacterial Keratitis, 115 patients with laboratory-proven fungal Keratitis, and 115 patients with laboratory-proven acanthamoeba Keratitis seen at Aravind Eye Hospital, Madurai, India, from 2006-2011. Risk factors and clinical features of the 3 organisms were compared using multinomial logistic regression. Results Of 95 patients with Bacterial Keratitis, 103 patients with fungal Keratitis, and 93 patients with acanthamoeba Keratitis who had medical records available for review, 287 (99%) did not wear contact lenses. Differentiating features were more common for acanthamoeba Keratitis than for Bacterial or fungal Keratitis. Compared to patients with Bacterial or fungal Keratitis, patients with acanthamoeba Keratitis were more likely to be younger and to have a longer duration of symptoms, and to have a ring infiltrate or disease confined to the epithelium. Conclusions Risk factors and clinical examination findings can be useful for differentiating acanthamoeba Keratitis from Bacterial and fungal Keratitis.
Thomas M Lietman - One of the best experts on this subject based on the ideXlab platform.
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cross linking assisted infection reduction clair a randomized clinical trial evaluating the effect of adjuvant cross linking on Bacterial Keratitis
Cornea, 2021Co-Authors: Venkatesh N Prajna, Prajna Lalitha, Jeremy D Keenan, Revathi Rajaraman, Ariana Austin, Naveen Radhakrishnan, Shivananda Narayana, Zijun Liu, Travis C Porco, Thomas M LietmanAbstract:Purpose To determine whether there is a benefit to adjuvant corneal cross-linking (CXL) for Bacterial Keratitis. Methods This is an outcome-masked, randomized controlled clinical trial. Consecutive patients presenting with a smear-positive Bacterial ulcer at Aravind Eye Hospitals at Madurai, Pondicherry, and Coimbatore in India were enrolled. Study eyes were randomized to topical moxifloxacin 0.5% or topical moxifloxacin 0.5% plus CXL. The primary outcome of the trial was microbiological cure at 24 hours on repeat culture. Secondary outcomes included best spectacle corrected visual acuity at 3 weeks and 3 months, percentage of study participants with epithelial healing at 3 weeks and 3 months, infiltrate and/or scar size at 3 weeks and 3 months, 3-day smear and culture, and adverse events. Results Those randomized to CXL had 0.60 decreased odds of culture positivity at 24 hours (95% confidence interval [CI]: 0.10-3.50; P = 0.65), 0.9 logarithm of the minimum angle of resolution lines worse visual acuity (95% CI: -2.8 to 4.6; P = 0.63), and 0.41-mm larger scar size (95% CI: -0.48 to 1.30; P = 0.38) at 3 months. We note fewer corneal perforations or need for therapeutic penetrating keratoplasty in the CXL group. Conclusions We were unable to confirm a benefit to adjuvant CXL in the primary treatment of moderate Bacterial Keratitis. However, CXL may reduce culture positivity and complication rates; therefore, a larger trial to fully evaluate this is warranted. Trial registration NCT02570321.
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empirical treatment of Bacterial Keratitis an international survey of corneal specialists
BMJ Open Ophthalmology, 2017Co-Authors: Ariana Austin, Thomas M Lietman, Julie M Schallhorn, Mike Geske, Mark J Mannis, Jennifer RosenussbaumerAbstract:Background/aims New antibiotic agents and changing susceptibility patterns may have changed the empirical treatment of Bacterial Keratitis. Our objective in this study was to survey cornea specialists’ practice patterns in the initial treatment of Bacterial ulcers. Methods This study consisted of a short online survey emailed to members of the Cornea Society listserv for an international sample of cornea specialists. Data collection began July 2014 and ended October 2014. Results A total of 1009 surveys were emailed, and we received 140 (14%) responses. The majority of US clinicians surveyed (n=83, 80%) chose fortified antibiotics empirically, with 55% (n=57) selecting fortified vancomycin and 16% (n=17) using fluoroquinolone alone. International respondents were twice as likely to use fluoroquinolone monotherapy (31%, n=11, p=0.07) and less likely to use fortified vancomycin (33%, n=12, p=0.03). Forty-five per cent (n=46) of US respondents reported that their initial antibiotic choice covered methicillin-resistant Staphylococcus aureus , compared with 22% (n=8) of international respondents (p Conclusion Practice patterns for the initial treatment of Bacterial Keratitis vary with clinicians in the USA being more likely to use fortified antibiotics versus fluoroquinolone monotherapy and more concerned with resistant organisms than their international peers.
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trends in antibiotic resistance in Bacterial Keratitis isolates from south india
British Journal of Ophthalmology, 2017Co-Authors: Prajna Lalitha, Jeena Mascarenhas, Muthiah Srinivasan, Namperumalsamy Venkatesh Prajna, Travis C Porco, Geetha Manoharan, Rajaram Karpagam, Manoranjan Das, Thomas M LietmanAbstract:Aims To report trends in antibiotic resistance in cases of Bacterial Keratitis from a large eye hospital in South India. Methods In this retrospective cross-sectional study, the microbiology laboratory records of patients with infectious Keratitis diagnosed at an eye hospital in South India from 2002 to 2013 were reviewed to determine the proportion with antibiotic non-susceptibility. Results 3685 Bacterial isolates had susceptibility testing performed over the 12-year period. The two most common organisms with resistance were Streptococcus pneumoniae (n=1204) and Pseudomonas aeruginosa (n=894). Antibiotic non-susceptibility was generally uncommon for these two organisms and no significant trends were detected over the course of the study. In contrast, Staphylococcus aureus (N=211) isolates demonstrated a significant increase in fluoroquinolone non-susceptibility over the 12-year study period. This coincided with a significant increase in methicillin-resistant S. aureus (MRSA) during the study period, though the increase in fluoroquinolone resistance was likewise seen in methicillin-sensitive S. aureus (MSSA). For example, ofloxacin resistance in MSSA increased from 11.1% in 2002 to 66.7% in 2013 (p=0.002). No trends were apparent for the aminoglycosides, cefazolin or vancomycin, for which in vitro non-susceptibility generally appeared to be low. Conclusion Resistance to antibiotics was generally stable for infectious Keratitis isolates from a large eye hospital in South India, except for S. aureus , which experienced a significant increase in fluoroquinolone resistance from 2002 to 2013. Fluoroquinolone antibiotics currently have poor in vitro activity against both MRSA and MSSA in South India and are therefore not the ideal therapy for Staphylococcal corneal ulcers.
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visual recovery in treated Bacterial Keratitis
Ophthalmology, 2014Co-Authors: Muthiah Srinivasan, Jeena Mascarenhas, Prajna Lalitha, Thomas M Lietman, Revathi Rajaraman, Meenakshi Ravindran, Kathryn J Ray, Michael E Zegans, Nisha R Acharya, Jeremy D KeenanAbstract:Bacterial Keratitis is a leading cause of visual impairment worldwide. However, the natural history of treated Bacterial Keratitis has not been well characterized. We performed a secondary analysis of the Steroids for Corneal Ulcers Trial (SCUT; clinicaltrials.gov #NCT00324168) to better characterize the rate of visual acuity improvement after successful antimicrobial treatment.
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acanthamoeba fungal and Bacterial Keratitis a comparison of risk factors and clinical features
American Journal of Ophthalmology, 2014Co-Authors: Jeena Mascarenhas, Prajna Lalitha, Venkatesh N Prajna, Muthiah Srinivasan, Sean S Dsilva, Catherine E Oldenburg, Durga S Borkar, Elizabeth Esterberg, Thomas M Lietman, Jeremy D KeenanAbstract:Purpose To determine risk factors and clinical signs that may differentiate between Bacterial, fungal, and acanthamoeba Keratitis among patients presenting with presumed infectious Keratitis. Design Hospital-based cross-sectional study. Methods We examined the medical records of 115 patients with laboratory-proven Bacterial Keratitis, 115 patients with laboratory-proven fungal Keratitis, and 115 patients with laboratory-proven acanthamoeba Keratitis seen at Aravind Eye Hospital, Madurai, India, from 2006-2011. Risk factors and clinical features of the 3 organisms were compared using multinomial logistic regression. Results Of 95 patients with Bacterial Keratitis, 103 patients with fungal Keratitis, and 93 patients with acanthamoeba Keratitis who had medical records available for review, 287 (99%) did not wear contact lenses. Differentiating features were more common for acanthamoeba Keratitis than for Bacterial or fungal Keratitis. Compared to patients with Bacterial or fungal Keratitis, patients with acanthamoeba Keratitis were more likely to be younger and to have a longer duration of symptoms, and to have a ring infiltrate or disease confined to the epithelium. Conclusions Risk factors and clinical examination findings can be useful for differentiating acanthamoeba Keratitis from Bacterial and fungal Keratitis.
Prajna Lalitha - One of the best experts on this subject based on the ideXlab platform.
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cross linking assisted infection reduction clair a randomized clinical trial evaluating the effect of adjuvant cross linking on Bacterial Keratitis
Cornea, 2021Co-Authors: Venkatesh N Prajna, Prajna Lalitha, Jeremy D Keenan, Revathi Rajaraman, Ariana Austin, Naveen Radhakrishnan, Shivananda Narayana, Zijun Liu, Travis C Porco, Thomas M LietmanAbstract:Purpose To determine whether there is a benefit to adjuvant corneal cross-linking (CXL) for Bacterial Keratitis. Methods This is an outcome-masked, randomized controlled clinical trial. Consecutive patients presenting with a smear-positive Bacterial ulcer at Aravind Eye Hospitals at Madurai, Pondicherry, and Coimbatore in India were enrolled. Study eyes were randomized to topical moxifloxacin 0.5% or topical moxifloxacin 0.5% plus CXL. The primary outcome of the trial was microbiological cure at 24 hours on repeat culture. Secondary outcomes included best spectacle corrected visual acuity at 3 weeks and 3 months, percentage of study participants with epithelial healing at 3 weeks and 3 months, infiltrate and/or scar size at 3 weeks and 3 months, 3-day smear and culture, and adverse events. Results Those randomized to CXL had 0.60 decreased odds of culture positivity at 24 hours (95% confidence interval [CI]: 0.10-3.50; P = 0.65), 0.9 logarithm of the minimum angle of resolution lines worse visual acuity (95% CI: -2.8 to 4.6; P = 0.63), and 0.41-mm larger scar size (95% CI: -0.48 to 1.30; P = 0.38) at 3 months. We note fewer corneal perforations or need for therapeutic penetrating keratoplasty in the CXL group. Conclusions We were unable to confirm a benefit to adjuvant CXL in the primary treatment of moderate Bacterial Keratitis. However, CXL may reduce culture positivity and complication rates; therefore, a larger trial to fully evaluate this is warranted. Trial registration NCT02570321.
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trends in antibiotic resistance in Bacterial Keratitis isolates from south india
British Journal of Ophthalmology, 2017Co-Authors: Prajna Lalitha, Jeena Mascarenhas, Muthiah Srinivasan, Namperumalsamy Venkatesh Prajna, Travis C Porco, Geetha Manoharan, Rajaram Karpagam, Manoranjan Das, Thomas M LietmanAbstract:Aims To report trends in antibiotic resistance in cases of Bacterial Keratitis from a large eye hospital in South India. Methods In this retrospective cross-sectional study, the microbiology laboratory records of patients with infectious Keratitis diagnosed at an eye hospital in South India from 2002 to 2013 were reviewed to determine the proportion with antibiotic non-susceptibility. Results 3685 Bacterial isolates had susceptibility testing performed over the 12-year period. The two most common organisms with resistance were Streptococcus pneumoniae (n=1204) and Pseudomonas aeruginosa (n=894). Antibiotic non-susceptibility was generally uncommon for these two organisms and no significant trends were detected over the course of the study. In contrast, Staphylococcus aureus (N=211) isolates demonstrated a significant increase in fluoroquinolone non-susceptibility over the 12-year study period. This coincided with a significant increase in methicillin-resistant S. aureus (MRSA) during the study period, though the increase in fluoroquinolone resistance was likewise seen in methicillin-sensitive S. aureus (MSSA). For example, ofloxacin resistance in MSSA increased from 11.1% in 2002 to 66.7% in 2013 (p=0.002). No trends were apparent for the aminoglycosides, cefazolin or vancomycin, for which in vitro non-susceptibility generally appeared to be low. Conclusion Resistance to antibiotics was generally stable for infectious Keratitis isolates from a large eye hospital in South India, except for S. aureus , which experienced a significant increase in fluoroquinolone resistance from 2002 to 2013. Fluoroquinolone antibiotics currently have poor in vitro activity against both MRSA and MSSA in South India and are therefore not the ideal therapy for Staphylococcal corneal ulcers.
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visual recovery in treated Bacterial Keratitis
Ophthalmology, 2014Co-Authors: Muthiah Srinivasan, Jeena Mascarenhas, Prajna Lalitha, Thomas M Lietman, Revathi Rajaraman, Meenakshi Ravindran, Kathryn J Ray, Michael E Zegans, Nisha R Acharya, Jeremy D KeenanAbstract:Bacterial Keratitis is a leading cause of visual impairment worldwide. However, the natural history of treated Bacterial Keratitis has not been well characterized. We performed a secondary analysis of the Steroids for Corneal Ulcers Trial (SCUT; clinicaltrials.gov #NCT00324168) to better characterize the rate of visual acuity improvement after successful antimicrobial treatment.
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visual outcomes in treated Bacterial Keratitis four years of prospective follow up
Investigative Ophthalmology & Visual Science, 2014Co-Authors: Scott M Mcclintic, Jeena Mascarenhas, Prajna Lalitha, Muthiah Srinivasan, Catherine E Oldenburg, Revathi Rajaraman, Kathryn J Ray, Namperumalsamy Venkatesh Prajna, Kieran S Obrien, Nisha R AcharyaAbstract:Purpose. We described the change in visual acuity experienced by eyes successfully treated for Bacterial Keratitis.
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acanthamoeba fungal and Bacterial Keratitis a comparison of risk factors and clinical features
American Journal of Ophthalmology, 2014Co-Authors: Jeena Mascarenhas, Prajna Lalitha, Venkatesh N Prajna, Muthiah Srinivasan, Sean S Dsilva, Catherine E Oldenburg, Durga S Borkar, Elizabeth Esterberg, Thomas M Lietman, Jeremy D KeenanAbstract:Purpose To determine risk factors and clinical signs that may differentiate between Bacterial, fungal, and acanthamoeba Keratitis among patients presenting with presumed infectious Keratitis. Design Hospital-based cross-sectional study. Methods We examined the medical records of 115 patients with laboratory-proven Bacterial Keratitis, 115 patients with laboratory-proven fungal Keratitis, and 115 patients with laboratory-proven acanthamoeba Keratitis seen at Aravind Eye Hospital, Madurai, India, from 2006-2011. Risk factors and clinical features of the 3 organisms were compared using multinomial logistic regression. Results Of 95 patients with Bacterial Keratitis, 103 patients with fungal Keratitis, and 93 patients with acanthamoeba Keratitis who had medical records available for review, 287 (99%) did not wear contact lenses. Differentiating features were more common for acanthamoeba Keratitis than for Bacterial or fungal Keratitis. Compared to patients with Bacterial or fungal Keratitis, patients with acanthamoeba Keratitis were more likely to be younger and to have a longer duration of symptoms, and to have a ring infiltrate or disease confined to the epithelium. Conclusions Risk factors and clinical examination findings can be useful for differentiating acanthamoeba Keratitis from Bacterial and fungal Keratitis.