1
|
Khor WB, Lakshminarayanan R, Periayah MH, Prajna VN, Garg P, Sharma N, Mehta JS, Young A, Goseyarakwong P, Puangsricharern V, Tan AL, Beuerman RW, Tan DTH. The antibiotic resistance profiles of Pseudomonas aeruginosa in the Asia Cornea Society Infectious Keratitis Study. Int Ophthalmol 2024; 44:361. [PMID: 39215853 PMCID: PMC11365837 DOI: 10.1007/s10792-024-03270-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2024] [Accepted: 07/29/2024] [Indexed: 09/04/2024]
Abstract
PURPOSE To describe the prevalence and antibiotic resistance profiles of Pseudomonas aeruginosa isolated from the Asia Cornea Society Infectious Keratitis Study (ACSIKS). METHODS All bacterial isolates from ACSIKS underwent repeat microbiological identification in a central repository in Singapore. Minimum inhibitory concentration (MIC) determination was conducted for isolates of P. aeruginosa against thirteen antibiotics from 6 different classes, and categorized based on Clinical Laboratory Standard Institutes' reference ranges. The percentage rates of resistance (non-susceptibility) to each antibiotic included isolates of both intermediate and complete resistance. Multi-drug resistance (MDR) was defined as non-susceptibility to at least one agent in three or more antimicrobial classes. RESULTS Of the 1493 unique bacterial specimens obtained from ACSIKS, 319 isolates were of P. aeruginosa. The majority of isolates were from centers in India (n = 118, 37%), Singapore (n = 90, 28.2%), Hong Kong (n = 31, 9.7%) and Thailand (n = 30, 9.4%). The cumulative antibiotic resistance rate was the greatest for polymyxin B (100%), ciprofloxacin (17.6%) and moxifloxacin (16.9%), and lowest for cefepime (11.6%) and amikacin (13.5%). Isolates from India demonstrated the highest antibiotic resistance rates of all the centers, and included moxifloxacin (47.5%) and ciprofloxacin (39.8%). Forty-eight of the 59 MDR isolates also originated from India. Antibiotic resistance rates were significantly lower in the other ACSIKS centers, and were typically less than 10%. CONCLUSIONS The antibiotic resistance profiles of P. aeruginosa varied between different countries. While it was low for most countries, substantial antibiotic resistance and a significant number of multi-drug resistant isolates were noted in the centers from India.
Collapse
Affiliation(s)
- Wei-Boon Khor
- Singapore National Eye Centre, Singapore, Singapore
- Singapore Eye Research Institute, Singapore, Singapore
- Duke-NUS Graduate Medical School, Singapore, Singapore
| | - Rajamani Lakshminarayanan
- Singapore Eye Research Institute, Singapore, Singapore
- Duke-NUS Graduate Medical School, Singapore, Singapore
- Department of Pharmacy, National University of Singapore, Singapore, Singapore
| | | | | | - Prashant Garg
- LV Prasad Eye Institute, Hyderabad, Telangana, India
| | - Namrata Sharma
- Dr. Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, Ansari Nagar, New Delhi, India
| | - Jodhbir S Mehta
- Singapore National Eye Centre, Singapore, Singapore
- Singapore Eye Research Institute, Singapore, Singapore
- Duke-NUS Graduate Medical School, Singapore, Singapore
| | - Alvin Young
- The Department of Ophthalmology and Visual Sciences, The Chinese University of Hong Kong, Hong Kong SAR, China
- Prince of Wales Hospital & Alice Ho Miu Ling Nethersole Hospital, Hong Kong SAR, China
| | - Panida Goseyarakwong
- Department of Ophthalmology, Faculty of Medicine, Siriraj Hospital, Mahidol University, Bangkok, Thailand
| | - Vilavun Puangsricharern
- Department of Ophthalmology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Ai Ling Tan
- Department of Microbiology, Singapore General Hospital, Singapore, Singapore
| | - Roger W Beuerman
- Singapore Eye Research Institute, Singapore, Singapore
- Duke-NUS Graduate Medical School, Singapore, Singapore
| | - Donald Tiang-Hwee Tan
- Singapore National Eye Centre, Singapore, Singapore.
- Singapore Eye Research Institute, Singapore, Singapore.
- Camden Medical Centre, 1 Orchard Blvd, #13-03, Singapore, 248649, Singapore.
| |
Collapse
|
2
|
Goss R, Adams VJ, Heinrich C, Grundon R, Linn-Pearl R, Scurrell E, Hamzianpour N. Progressive ulcerative keratitis in dogs in the United Kingdom: Microbial isolates, antimicrobial sensitivity, and resistance patterns. Vet Ophthalmol 2024; 27:330-346. [PMID: 37933885 DOI: 10.1111/vop.13160] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2023] [Revised: 10/17/2023] [Accepted: 10/24/2023] [Indexed: 11/08/2023]
Abstract
OBJECTIVES The objective of the study was to identify bacterial pathogens and their antimicrobial sensitivity profile associated with cases of canine progressive ulcerative keratitis. MATERIALS AND METHODS Analysis of microbial culture and sensitivity results from dogs with progressive ulcerative keratitis presenting to a UK referral practice between December 2018 and August 2020. RESULTS Positive bacterial cultures were obtained from 80/148 (54%) of the canine ulcers sampled with 99 bacterial isolates cultured. Streptococcus canis (n = 29), Pseudomonas aeruginosa (n = 19), and Staphylococcus pseudintermedius (n = 16) were the most common isolates. Pseudomonas aeruginosa was more likely to be isolated whether the ulcer was clinically malacic at the time of sampling (OR = 10.1, p < .001). Ulcers treated prior to culture with fusidic acid were 7.6 times more likely to be positive than those treated with any other antimicrobial(s). Bacterial isolates demonstrated resistance against neomycin (85%), fusidic acid (78%), and tetracycline (68%). Conversely, isolates were most likely to be sensitive to gentamicin (88%), ofloxacin (77%), ciprofloxacin (73%), and chloramphenicol (64%). Antimicrobial combinations of chloramphenicol or gentamicin with a fluoroquinolone (ofloxacin or ciprofloxacin) or chloramphenicol combined with gentamicin were the most effective on in vitro analysis (over 90% susceptibility of all isolates). CONCLUSION The most common bacterial species associated with canine progressive ulcerative keratitis in a UK referral population were S. canis, P. aeruginosa, and S. pseudintermedius. Combination antimicrobial therapy is recommended pending culture and sensitivity results given the varied antimicrobial susceptibility profiles and significant bacterial in vitro resistance to antimicrobial monotherapy.
Collapse
|
3
|
Romanowski EG, Mumper SM, Shanks HQ, Yates KA, Mandell JB, Zegans ME, Shanks RM. Cefiderocol Is an Effective Topical Monotherapy for Experimental Extensively Drug-Resistant Pseudomonas aeruginosa Keratitis. OPHTHALMOLOGY SCIENCE 2024; 4:100452. [PMID: 38560275 PMCID: PMC10973669 DOI: 10.1016/j.xops.2023.100452] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/30/2023] [Accepted: 12/04/2023] [Indexed: 04/04/2024]
Abstract
Purpose To test cefiderocol, a siderophore-cephalosporin antibiotic for topical monotherapy treatment of experimental extensively drug-resistant (XDR) Pseudomonas aeruginosa keratitis. Design Preclinical study. Subjects and Controls Deidentified P. aeruginosa keratitis isolates, XDR P. aeruginosa from eye drop outbreak, rabbits, saline, cefiderocol 50 mg/ml, ciprofloxacin 0.3%, and tobramycin 14 mg/ml. Methods Intervention or Testing Cefiderocol antibacterial activity against P. aeruginosa keratitis isolates (n = 135) was evaluated by minimum inhibitory concentration (MIC) testing. Ocular toxicity/tolerability and antibacterial efficacy were tested in vivo with experimental rabbit models. Corneal concentrations and stability were assessed using a bioassay. Main Outcome Measures Minimum inhibitory concentration analysis for susceptibility, graded tests for ocular toxicity/tolerability, colony-forming unit (CFU) analysis for bacterial burden, corneal cefiderocol concentrations. Results One hundred percent of P. aeruginosa keratitis isolates were susceptible to cefiderocol (n = 135), the MIC90 was 0.125 μg/ml including the XDR isolate (MIC = 0.125 μg/ml). Topical cefiderocol 50 mg/ml was minimally toxic to the ocular surface and was well tolerated. For the XDR P. aeruginosa isolate, topical cefiderocol 50 mg/ml, significantly decreased corneal CFU compared with ciprofloxacin 0.3%, tobramycin 14 mg/ml, and saline. In addition, tobramycin 14 mg/ml was more effective than the saline control. Mean cefiderocol corneal concentrations were 191× greater than the MIC90 of the P. aeruginosa keratitis isolates. Refrigerated cefiderocol maintained antimicrobial activity over a 1-month period. Conclusions These results demonstrate that cefiderocol is well tolerated on rabbit corneas and is effective against P. aeruginosa keratitis isolates in vitro and was effective in vivo against an XDR isolate in a rabbit keratitis model. Given the recent outbreak of keratitis caused by this XDR P. aeruginosa, cefiderocol is a promising additional antibiotic that should be further evaluated for topical treatment of keratitis caused by antibiotic resistant P. aeruginosa. Financial Disclosures Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.
Collapse
Affiliation(s)
- Eric G. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Sonya M. Mumper
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Hazel Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Kathleen A. Yates
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Jonathan B. Mandell
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| | - Michael E. Zegans
- Department of Surgery, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, New Hampshire
| | - Robert M.Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania
| |
Collapse
|
4
|
Romanowski EG, Mumper SM, Shanks HQ, Yates KA, Mandell JB, Zegans ME, Shanks RMQ. Cefiderocol is an effective topical monotherapy for experimental extensively-drug resistant Pseudomonas aeruginosa keratitis. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.08.31.555778. [PMID: 37693441 PMCID: PMC10491197 DOI: 10.1101/2023.08.31.555778] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/12/2023]
Abstract
Purpose To test cefiderocol, a siderophore-cephalosporin antibiotic for topical monotherapy treatment of experimental extensively drug resistant (XDR) Pseudomonas aeruginosa keratitis. Design Preclinical study. Subjects and Controls Deidentified P. aeruginosa keratitis isolates, XDR P. aeruginosa from eye drop outbreak, rabbits, saline, cefiderocol 50 mg/ml, ciprofloxacin 0.3%, and tobramycin 14 mg/ml. Methods Intervention or Testing Cefiderocol antibacterial activity against P. aeruginosa keratitis isolates (n=135) was evaluated by minimum inhibitory concentration (MIC) testing. Ocular toxicity/tolerability and antibacterial efficacy were tested in vivo with experimental rabbit models. Corneal concentrations and stability were assessed using a bioassay. Main Outcome Measures MIC analysis for susceptibility, graded tests for ocular toxicity/tolerability, CFU analysis for bacterial burden, corneal cefiderocol concentrations. Results 100% of P. aeruginosa keratitis isolates were susceptible to cefiderocol (n=135), the MIC90 was 0.125 μg/ml including the XDR isolate (MIC = 0.125 μg/ml). Topical cefiderocol 50 mg/ml was minimally toxic to the ocular surface and was well tolerated. For the XDR P. aeruginosa isolate, topical cefiderocol 50 mg/ml, significantly decreased corneal CFU compared to ciprofloxacin 0.3%, tobramycin 14 mg/ml, and saline. In addition, tobramycin 14 mg/ml was more effective than the saline control. Mean cefiderocol corneal concentrations were 191x greater than the MIC90 of the P. aeruginosa keratitis isolates. Refrigerated cefiderocol maintained antimicrobial activity over a one-month period. Conclusions These results demonstrate that cefiderocol is well tolerated on rabbit corneas and is effective against P. aeruginosa keratitis isolates in vitro and was effective in vivo against an XDR isolate in a rabbit keratitis model. Given the recent outbreak of keratitis caused by this XDR P. aeruginosa, cefiderocol is a promising additional antibiotic that should be further evaluated for topical treatment of keratitis caused by antibiotic resistant P. aeruginosa.
Collapse
Affiliation(s)
- Eric G. Romanowski
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Sonya M. Mumper
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Hazel Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Kathleen A. Yates
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Jonathan B. Mandell
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| | - Michael E. Zegans
- Department of Surgery, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH, USA
| | - Robert M. Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, Pennsylvania, USA
| |
Collapse
|
5
|
Romanowski EG, Yates KA, Romanowski JE, Shanks RMQ, Kowalski RP. The in vitro Evaluation of the Activity of COVID-19 Antiviral Drugs Against Adenovirus. Clin Ophthalmol 2022; 15:4787-4793. [PMID: 35221670 PMCID: PMC8866980 DOI: 10.2147/opth.s340576] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 12/03/2021] [Indexed: 12/02/2022] Open
Abstract
Purpose Presently, there is no approved antiviral therapy for adenovirus (HAdV) ocular infections. During the COVID-19 pandemic, increased attention has been focused on antiviral treatments. Remdesivir, hydroxychloroquine, ivermectin, and umifenovir (Arbidol) have been touted as potential antiviral treatments for COVID-19. The goal of the current study was to determine whether these potential COVID-19 antivirals produce in vitro antiviral activity against a panel of ocular adenovirus types. Methods The 50% effective concentrations (EC50) of remdesivir (REM), hydroxychloroquine (HCQ), ivermectin (IVM), umifenovir (UMF) and cidofovir (CDV) (positive antiviral control) were determined for the human HAdV types HAdV3, HAdV4, HAdV5, HAdV7a, HAdV8, HAdV19/64 and HAdV37 using standard plaque-reduction assays in A549 cells. Results The range of mean in vitro EC50 concentrations for each antiviral across the range of HAdV types is as follows: The positive antiviral control, CDV, ranged from 0.47 to 9.62 µM; REM ranged from 0.21 to 11.27 µM; UMF ranged from 3.72 to 64.8 µM; IVR ranged from 2.60 to 201.3 µM; and HCQ was >10 µM for all Ad types because of toxicity to the A549 cells. REM produced lower EC50 concentrations than CDV for 6 of 7 HAdV types. Potency increases with lower EC50 concentrations. Conclusion REM demonstrated anti-adenovirus activity in a range similar to that demonstrated by cidofovir. UMF and IVR demonstrated larger ranges of antiviral activity than CDV and REM across the panel of HAdV types. The anti-adenovirus activity of HCQ could not be determined due to cytotoxicity. Further investigation of REM, UMF, and IVR as antivirals for adenovirus is indicated.
Collapse
Affiliation(s)
- Eric G Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Kathleen A Yates
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - John E Romanowski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Robert M Q Shanks
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Regis P Kowalski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, UPMC Eye Center, Ophthalmology and Visual Sciences Research Center, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| |
Collapse
|
6
|
Kowalski RP, Nayyar SV, Romanowski EG, Jhanji V. Anti-Infective Treatment and Resistance Is Rarely Problematic with Eye Infections. Antibiotics (Basel) 2022; 11:antibiotics11020204. [PMID: 35203807 PMCID: PMC8868068 DOI: 10.3390/antibiotics11020204] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 02/01/2022] [Accepted: 02/03/2022] [Indexed: 11/16/2022] Open
Abstract
The treatment of eye infections is very different than treating other body infections that require systemic anti-infectives. Endophthalmitis, keratitis, conjunctivitis, and other ocular infections are treated with direct injection and with topical drops directly to the infection site. There are no anti-infective susceptibility standards to interpret treatment success, but the systemic standards can be used to guide ocular therapy if the concentration of anti-infective in the ocular tissue is assumed to be higher than the concentration in the blood serum. This Perspective describes: (1) eye infections, (2) diagnostics of eye infections, (3) anti-infective treatment of eye infections, (4) anti-infective resistance of ocular pathogens, and (5) alternative anti-infective delivery and therapy. The data, based on years of clinical and laboratory research, support the premise that ocular infections are less problematic if etiologic agents are laboratory-diagnosed and if prompt, potent, anti-infective therapy is applied. Anti-infective susceptibility should be monitored to assure continued therapeutic success and the possibility of new-found resistance. New delivery systems and therapies may be helpful to better treat future ocular infections.
Collapse
Affiliation(s)
- Regis P. Kowalski
- Department of Ophthalmology, The Eye and Ear Institute, School of Medicine, University of Pittsburgh, 203 Lothrop Street, Pittsburgh, PA 15213, USA; (E.G.R.); (V.J.)
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center, The Eye and Ear Institute, University of Pittsburgh School of Medicine, 203 Lothrop Street, Room 642, Pittsburgh, PA 15213, USA;
- Correspondence: ; Tel.: +1-412-647-7211
| | - Shannon V. Nayyar
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center, The Eye and Ear Institute, University of Pittsburgh School of Medicine, 203 Lothrop Street, Room 642, Pittsburgh, PA 15213, USA;
| | - Eric G. Romanowski
- Department of Ophthalmology, The Eye and Ear Institute, School of Medicine, University of Pittsburgh, 203 Lothrop Street, Pittsburgh, PA 15213, USA; (E.G.R.); (V.J.)
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center, The Eye and Ear Institute, University of Pittsburgh School of Medicine, 203 Lothrop Street, Room 642, Pittsburgh, PA 15213, USA;
| | - Vishal Jhanji
- Department of Ophthalmology, The Eye and Ear Institute, School of Medicine, University of Pittsburgh, 203 Lothrop Street, Pittsburgh, PA 15213, USA; (E.G.R.); (V.J.)
- The Charles T. Campbell Eye Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh Medical Center, The Eye and Ear Institute, University of Pittsburgh School of Medicine, 203 Lothrop Street, Room 642, Pittsburgh, PA 15213, USA;
| |
Collapse
|
7
|
RP-HPLC-UV validation method for levofloxacin hemihydrate estimation in the nano polymeric ocular preparation. ARAB J CHEM 2022. [DOI: 10.1016/j.arabjc.2021.103582] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
|
8
|
Harshaw NS, Stella NA, Lehner KM, Romanowski EG, Kowalski RP, Shanks RMQ. Antibiotics Used in Empiric Treatment of Ocular Infections Trigger the Bacterial Rcs Stress Response System Independent of Antibiotic Susceptibility. Antibiotics (Basel) 2021; 10:antibiotics10091033. [PMID: 34572615 PMCID: PMC8470065 DOI: 10.3390/antibiotics10091033] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2021] [Revised: 08/18/2021] [Accepted: 08/21/2021] [Indexed: 12/02/2022] Open
Abstract
The Rcs phosphorelay is a bacterial stress response system that responds to envelope stresses and in turn controls several virulence-associated pathways, including capsule, flagella, and toxin biosynthesis, of numerous bacterial species. The Rcs system also affects antibiotic tolerance, biofilm formation, and horizontal gene transfer. The Rcs system of the ocular bacterial pathogen Serratia marcescens was recently demonstrated to influence ocular pathogenesis in a rabbit model of keratitis, with Rcs-defective mutants causing greater pathology and Rcs-activated strains demonstrating reduced inflammation. The Rcs system is activated by a variety of insults, including β-lactam antibiotics and polymyxin B. In this study, we developed three luminescence-based transcriptional reporters for Rcs system activity and used them to test whether antibiotics used for empiric treatment of ocular infections influence Rcs system activity in a keratitis isolate of S. marcescens. These included antibiotics to which the bacteria were susceptible and resistant. Results indicate that cefazolin, ceftazidime, polymyxin B, and vancomycin activate the Rcs system to varying degrees in an RcsB-dependent manner, whereas ciprofloxacin and tobramycin activated the promoter fusions, but in an Rcs-independent manner. Although minimum inhibitory concentration (MIC) analysis demonstrated resistance of the test bacteria to polymyxin B and vancomycin, the Rcs system was activated by sub-inhibitory concentrations of these antibiotics. Together, these data indicate that a bacterial stress system that influences numerous pathogenic phenotypes and drug-tolerance is influenced by different classes of antibiotics despite the susceptibility status of the bacterium.
Collapse
|
9
|
McKeever JM, Ward DA, Hendrix DVH. Comparison of antimicrobial resistance patterns in dogs with bacterial keratitis presented to a veterinary teaching hospital over two multi-year time periods (1993-2003 and 2013-2019) in the Southeastern United States. Vet Ophthalmol 2021; 24:653-658. [PMID: 34037320 DOI: 10.1111/vop.12897] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/24/2021] [Accepted: 04/27/2021] [Indexed: 01/14/2023]
Abstract
OBJECTIVE To report clinical characteristics of dogs with bacterial keratitis, identify the most common bacterial isolates within this population, characterize the bacterial isolates' antimicrobial resistance patterns, and compare those resistance patterns to previously reported resistance patterns. ANIMAL STUDIED Dogs diagnosed with bacterial keratitis between 2013 and 2019. PROCEDURES Data pertaining to breed; Schirmer tear test I results; use of cyclosporine, tacrolimus, or corticosteroids at time of ulcer diagnosis; bacterial genus or species isolated; and resistance to selected antimicrobials as measured by Kirby-Bauer disk diffusion were collected. Resistance patterns were compared to those reported by Tolar et al. (2006). RESULTS One hundred seventy bacterial isolates were cultured from 138 eyes from 130 dogs. Of these dogs, 45% were brachycephalic, 62% had STT <15 mm/min, and 28% were receiving a corticosteroid at the time of examination. The most common isolates were Staphylococcus pseudintermedius (31%), β-hemolytic Streptococcus spp. (28%), and Pseudomonas aeruginosa (18%). Compared to the 1993-2003 study period, there were significant increases in resistance to cephalothin and polymyxin B among S. pseudintermedius isolates. β-hemolytic Streptococcus spp. and P. aeruginosa isolates had no significant changes in resistance to the tested antimicrobials. CONCLUSION Isolates of S. pseudintermedius, β-hemolytic Streptococcus spp., and P. aeruginosa had minimal changes in resistance between the two study periods. In this population, monotherapy with ciprofloxacin or combination therapy of tobramycin and a first-generation cephalosporin continue to be appropriate for use in cases of suspected bacterial keratitis while awaiting results of susceptibility testing.
Collapse
Affiliation(s)
- Jeremy M McKeever
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN, USA.,Animal Clinic Inc. of Chattanooga, Chattanooga, TN, USA
| | - Daniel A Ward
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN, USA
| | - Diane V H Hendrix
- Department of Small Animal Clinical Sciences, College of Veterinary Medicine, University of Tennessee, Knoxville, TN, USA
| |
Collapse
|
10
|
Topical Vancomycin 5% Is More Efficacious Than 2.5% and 1.25% for Reducing Viable Methicillin-Resistant Staphylococcus aureus in Infectious Keratitis. Cornea 2020; 39:250-253. [PMID: 31658169 DOI: 10.1097/ico.0000000000002186] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE Topical vancomycin 5% (50 mg/mL) has been used for the treatment of methicillin-resistant Staphylococcus aureus (MRSA) keratitis, but patient comfort has many clinicians using lower concentrations. We compared the efficacy of different concentrations of vancomycin in the treatment of experimental MRSA keratitis. METHODS The corneas of 45 rabbits were infected with 2000 colony-forming units (CFUs) of MRSA. Corneal epithelium was abraded in the left eyes to mimic corneal ulceration. After 4 hours, the corneal CFUs were determined at the onset of treatment. The remaining rabbits were divided into 4 treatment groups (n = 9): 1) vancomycin 5%, 2) vancomycin 2.5%, 3) vancomycin 1.25%, and 4) saline. The rabbits were treated topically in both eyes every 15 minutes for 5 hours. One hour after treatment, the rabbits were clinically examined and euthanized, corneas were removed, and CFUs were determined to analyze vancomycin penetration, treatment efficacy, and bactericidal effect. RESULTS Ocular toxicity was concentration dependent from mild to moderate. For the abraded corneas, the CFUs of the vancomycin 5% group were lower than 2.5% and 1.25%, and all vancomycin groups were lower than saline. The CFUs of 2.5% were lower but similar to 1.25%. The vancomycin 5% group demonstrated a bactericidal effect and the best penetration. The CFUs of the abraded corneas treated with saline were lower than those of the intact corneas, indicating a possible antibacterial effect from the ocular surface. CONCLUSIONS Vancomycin 5% was most potent for treating experimental MRSA keratitis. The clinician may need to reassess treatment regarding antibacterial efficacy and patient comfort.
Collapse
|
11
|
Kokuti R. Medical treatment of keratomalacia in a cat. VETERINARY RECORD CASE REPORTS 2019. [DOI: 10.1136/vetreccr-2019-000820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
|
12
|
Brothers KM, Callaghan JD, Stella NA, Bachinsky JM, AlHigaylan M, Lehner KL, Franks JM, Lathrop KL, Collins E, Schmitt DM, Horzempa J, Shanks RMQ. Blowing epithelial cell bubbles with GumB: ShlA-family pore-forming toxins induce blebbing and rapid cellular death in corneal epithelial cells. PLoS Pathog 2019; 15:e1007825. [PMID: 31220184 PMCID: PMC6586354 DOI: 10.1371/journal.ppat.1007825] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2018] [Accepted: 05/07/2019] [Indexed: 12/18/2022] Open
Abstract
Medical devices, such as contact lenses, bring bacteria in direct contact with human cells. Consequences of these host-pathogen interactions include the alteration of mammalian cell surface architecture and induction of cellular death that renders tissues more susceptible to infection. Gram-negative bacteria known to induce cellular blebbing by mammalian cells, Pseudomonas and Vibrio species, do so through a type III secretion system-dependent mechanism. This study demonstrates that a subset of bacteria from the Enterobacteriaceae bacterial family induce cellular death and membrane blebs in a variety of cell types via a type V secretion-system dependent mechanism. Here, we report that ShlA-family cytolysins from Proteus mirabilis and Serratia marcescens were required to induce membrane blebbling and cell death. Blebbing and cellular death were blocked by an antioxidant and RIP-1 and MLKL inhibitors, implicating necroptosis in the observed phenotypes. Additional genetic studies determined that an IgaA family stress-response protein, GumB, was necessary to induce blebs. Data supported a model where GumB and shlBA are in a regulatory circuit through the Rcs stress response phosphorelay system required for bleb formation and pathogenesis in an invertebrate model of infection and proliferation in a phagocytic cell line. This study introduces GumB as a regulator of S. marcescens host-pathogen interactions and demonstrates a common type V secretion system-dependent mechanism by which bacteria elicit surface morphological changes on mammalian cells. This type V secretion-system mechanism likely contributes bacterial damage to the corneal epithelial layer, and enables access to deeper parts of the tissue that are more susceptible to infection.
Collapse
Affiliation(s)
- Kimberly M. Brothers
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA United States of America
- Charles T. Campbell Laboratory of Ophthalmic Microbiology
| | - Jake D. Callaghan
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA United States of America
- Charles T. Campbell Laboratory of Ophthalmic Microbiology
| | - Nicholas A. Stella
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA United States of America
- Charles T. Campbell Laboratory of Ophthalmic Microbiology
| | - Julianna M. Bachinsky
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA United States of America
- Charles T. Campbell Laboratory of Ophthalmic Microbiology
| | - Mohammed AlHigaylan
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA United States of America
- Charles T. Campbell Laboratory of Ophthalmic Microbiology
| | - Kara L. Lehner
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA United States of America
- Charles T. Campbell Laboratory of Ophthalmic Microbiology
| | - Jonathan M. Franks
- Center for Biological Imaging, University of Pittsburgh, Pittsburgh, PA United States of America
| | - Kira L. Lathrop
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA United States of America
| | - Elliot Collins
- Department of Natural Sciences and Mathematics, West Liberty University, West Liberty, WV United States of America
| | - Deanna M. Schmitt
- Department of Natural Sciences and Mathematics, West Liberty University, West Liberty, WV United States of America
| | - Joseph Horzempa
- Department of Natural Sciences and Mathematics, West Liberty University, West Liberty, WV United States of America
| | - Robert M. Q. Shanks
- Department of Ophthalmology, University of Pittsburgh, Pittsburgh, PA United States of America
- Charles T. Campbell Laboratory of Ophthalmic Microbiology
- * E-mail:
| |
Collapse
|
13
|
In Vitro Evaluation of a Hypochlorous Acid Hygiene Solution on Established Biofilms. Eye Contact Lens 2018; 44 Suppl 2:S187-S191. [PMID: 29369234 DOI: 10.1097/icl.0000000000000456] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
OBJECTIVES The purpose of this study was to determine whether a commercial formulation of hypochlorous acid hygiene solution (0.01%), Avenova, can destroy existing biofilms formed by ocular clinical bacterial isolates, including blepharitis isolates of Staphylococcus aureus and coagulase-negative staphylococci, and a keratitis isolate of Pseudomonas aeruginosa. METHODS Biofilms grown in bacterial growth media on disposable contact lens cases were challenged with hypochlorous acid hygiene solution. At various time points, surviving bacteria were quantified by serial dilution and colony counts. Staphylococcus aureus biofilms formed on glass were challenged using a hypochlorous acid hygiene solution and imaged using vital staining and confocal laser scanning microscopy. RESULTS Bactericidal activity (≥3 Log10; 99.9%) was observed for all tested bacterial species after a 30-min exposure. Staphylococcus aureus biofilms had a bactericidal level of killing by 10 min (P<0.01), Staphylococcus capitis by 5 min (P<0.001), Staphylococcus epidermidis by 30 min (P<0.001), and P. aeruginosa by 10 min (P<0.01). Confocal microscopy and crystal violet staining analysis of bacterial biofilms treated with hypochlorous acid solution both demonstrated that biofilm bacteria were readily killed, but biofilm structure was largely maintained. CONCLUSIONS Hypochlorous acid (0.01%) hygiene solution was able to achieve bactericidal levels of killing of bacteria in biofilms but did not disrupt biofilm structures. Susceptibility of tested staphylococcal blepharitis isolates varied by species, with S. capitis being the most susceptible and S. epidermidis being the least susceptible.
Collapse
|
14
|
Brothers KM, Kowalski RP, Tian S, Kinchington PR, Shanks RMQ. Bacteria induce autophagy in a human ocular surface cell line. Exp Eye Res 2017; 168:12-18. [PMID: 29288646 DOI: 10.1016/j.exer.2017.12.010] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2017] [Accepted: 12/24/2017] [Indexed: 12/18/2022]
Abstract
Autophagy protects cells from intracellular pathogens, but can be exploited by some infectious agents to their benefit. Currently it is not known if bacteria induce autohpagy in cells of the cornea. The goal of this study was to develop an ocular surface autophagy reporter cell line and determine whether ocular bacterial pathogens influence host responses through autophagy induction. The cell line was made using lentivirus transduction of an LC3-GFP fusion protein in human corneal limbal epithelial (HCLE) cells. LC3-GFP puncta in HCLEs were induced by rapamycin and ammonium chloride treatments, and prevented by the autophagy inhibitors 3-methyladenine (3'MA) and bafilomycin. Importantly, secretomes from Escherichia coli, Serratia marcescens, Staphylococcus aureus, methicillin sensitive (MSSA) and resistant (MRSA), were found to induce autophagy, whereas other bacteria, including Acinetobacter baumannii, Achromobacter xylosoxidans, Enterococcus faecalis, Klebsiella pneumoniae, Moraxella sp., and Stenotrophomonas maltophilia, did not. Our data indicates differences between tested ocular isolates of MRSA and MSSA in the activation of autophagy. HCLEs treated with 3'MA were slightly more susceptible to cytotoxic factors produced by S. marcescens and MRSA keratitis isolates, by contrast, bafilomycin A1 treatment caused no difference. This work demonstrates the successful development and validation of an autophagy reporter corneal cell line and indicates differences between ocular bacterial isolates in the activation of autophagy.
Collapse
Affiliation(s)
- Kimberly M Brothers
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Regis P Kowalski
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Shenghe Tian
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Paul R Kinchington
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA
| | - Robert M Q Shanks
- The Charles T. Campbell Ophthalmic Microbiology Laboratory, Department of Ophthalmology, University of Pittsburgh School of Medicine, Pittsburgh, PA, USA.
| |
Collapse
|
15
|
Guo L, Kong Q, Dong Z, Dong W, Fu X, Su L, Tan X. NLRC3 promotes host resistance against Pseudomonas aeruginosa-induced keratitis by promoting the degradation of IRAK1. Int J Mol Med 2017; 40:898-906. [DOI: 10.3892/ijmm.2017.3077] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2016] [Accepted: 07/17/2017] [Indexed: 11/06/2022] Open
|
16
|
Suzuki T, Yamamoto T, Ohashi Y. The antibacterial activity of levofloxacin eye drops against staphylococci using an in vitro pharmacokinetic model in the bulbar conjunctiva. J Infect Chemother 2016; 22:360-5. [PMID: 27036073 DOI: 10.1016/j.jiac.2016.01.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2015] [Revised: 01/07/2016] [Accepted: 01/19/2016] [Indexed: 11/18/2022]
Abstract
The incidence of fluoroquinolone-resistant staphylococcal isolates from the conjunctival sac is increasing. We compared pharmacological effects of levofloxacin (LVFX) against Staphylococcus epidermidis using an in vitro pharmacokinetic (PK) model simulating the concentration in the bulbar conjunctiva after applying eye drops of 0.5% and 1.5% LVFX. We used S. epidermidis conjunctival sac isolates [minimum inhibitory concentrations (MICs) of LVFX, 0.125 μg/mL]. LVFX-resistant strains were obtained from parental strains after culture with LVFX. The in vitro PK model simulated the concentration in the bulbar conjunctiva following three topical applications of 0.5% or 1.5% LVFX ophthalmic solution (0, 4, and 8 h) to rabbit eyes. Parental and LVFX-resistant strains were exposed to LVFX in the in vitro PK model, and changes in viable bacterial counts were evaluated for 12 h. The MICs of LVFX for the resistant isolates were 2-32 times higher than the parental strain, and those with MICs ≥2 ug/mL had mutations in the quinolone resistance-determining region. The PK model simulation predicts that 1.5% LVFX exerts bactericidal and bacteriostatic effects against strains with MICs of 0.125-2 and 4 μg/mL, respectively, whereas 0.5% LVFX would only be effective against strains with MICs of 0.125-1 μg/mL. The PK model predicts that the 1.5% LVFX ophthalmic solution exhibits a stronger bactericidal effect against resistant staphylococci in the bulbar conjunctiva than the 0.5% LVFX ophthalmic solution.
Collapse
Affiliation(s)
- Takashi Suzuki
- Department of Ophthalmology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan.
| | - Toshihiro Yamamoto
- Department of Ophthalmology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan
| | - Yuichi Ohashi
- Department of Ophthalmology, Ehime University Graduate School of Medicine, Shitsukawa, Toon, Ehime, 791-0295, Japan
| |
Collapse
|
17
|
Paradiso P, Serro AP, Saramago B, Colaço R, Chauhan A. Controlled Release of Antibiotics From Vitamin E–Loaded Silicone-Hydrogel Contact Lenses. J Pharm Sci 2016; 105:1164-72. [DOI: 10.1016/s0022-3549(15)00193-8] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2015] [Revised: 11/12/2015] [Accepted: 11/20/2015] [Indexed: 11/24/2022]
|
18
|
Chen K, Fu Q, Li D, Wu Y, Sun S, Zhang X. Wnt3a suppresses Pseudomonas aeruginosa-induced inflammation and promotes bacterial killing in macrophages. Mol Med Rep 2016; 13:2439-46. [PMID: 26846714 PMCID: PMC4768980 DOI: 10.3892/mmr.2016.4869] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2015] [Accepted: 01/11/2016] [Indexed: 12/31/2022] Open
Abstract
Pseudomonas aeruginosa (PA) is a common Gram‑negative bacterium and can cause serious infections, including hospital‑acquired pneumonia, suppurative bacterial keratitis and acute burn wound infection. The pathogenesis of PA infections is closely associated with excessive inflammatory responses and bacterial virulence factors. Wingless‑type MMTV integration site family, member 3A (Wnt3a), an upstream mediator in the canonical Wnt signaling pathway, has been implicated as a regulator of inflammation. However, its role in PA‑induced inflammation and bacterial clearance remains unknown. In the present study, the efficacy of Wnt3a conditioned media (Wnt3a‑CM) was assessed using western blotting and immunofluorescence, which showed that β‑catenin, a downstream molecule of Wnt3a, was upregulated and translocated to the nucleus following exposure to 50% Wnt3a‑CM for 6 h. To explore the role of Wnt3a in PA‑induced inflammation, the mRNA levels of pro‑inflammatory cytokines and apoptosis in macrophages were measured using reverse transcription‑quantitative polymerase chain reaction and flow cytometry, respectively. This indicated that Wnt3a suppressed inflammation by reducing the production of pro‑inflammatory cytokines and by promoting apoptosis in macrophages. Furthermore, the mechanism of macrophage‑mediated bacterial killing was investigated, and the results indicated that Wnt3a enhanced macrophage‑mediated intracellular bacterial killing via the induction of the production of cathelicidin‑related antimicrobial peptide and β‑defensins 1. Taken together, the current study explored the role of Wnt3a in inflammation and bacterial invasion, which may provide an improved understanding of host resistance to PA infection.
Collapse
Affiliation(s)
- Kang Chen
- Division of Clinical Laboratory, Zhongshan Hospital of Sun Yat‑Sen University, Zhongshan, Guangdong 528403, P.R. China
| | - Qiang Fu
- Division of Clinical Laboratory, Zhongshan Hospital of Sun Yat‑Sen University, Zhongshan, Guangdong 528403, P.R. China
| | - Dandan Li
- Department of Immunology, Institute of Human Virology, Zhongshan School of Medicine, Sun Yat‑Sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Yongjian Wu
- Department of Immunology, Institute of Human Virology, Zhongshan School of Medicine, Sun Yat‑Sen University, Guangzhou, Guangdong 510080, P.R. China
| | - Shijun Sun
- Division of Clinical Laboratory, Zhongshan Hospital of Sun Yat‑Sen University, Zhongshan, Guangdong 528403, P.R. China
| | - Xiumin Zhang
- Division of Clinical Laboratory, Zhongshan Hospital of Sun Yat‑Sen University, Zhongshan, Guangdong 528403, P.R. China
| |
Collapse
|
19
|
Romanowski EG, Kowalski TA, O'Connor KE, Yates KA, Mah FS, Shanks RMQ, Kowalski RP. The In Vitro Evaluation of Tigecycline and the In Vivo Evaluation of RPX-978 (0.5% Tigecycline) as an Ocular Antibiotic. J Ocul Pharmacol Ther 2015; 32:119-26. [PMID: 26545167 DOI: 10.1089/jop.2015.0095] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
PURPOSE The goals of the current study were to determine the in vitro antibacterial activity of tigecycline against multiple clinically relevant ocular pathogens and to evaluate the in vivo ocular tolerability and efficacy of 0.5% tigecycline in a methicillin-resistant Staphylococcus aureus (MRSA) keratitis model. METHODS In vitro: Minimum inhibitory concentrations (MICs) were determined for 110 clinical conjunctivitis isolates, 26 keratitis isolates of Pseudomonas aeruginosa, and 10 endophthalmitis isolates each of MRSA, methicillin-susceptible S. aureus (MSSA), MR, and MS coagulase-negative Staphylococcus. TOLERABILITY Six uninfected rabbits were topically treated in both eyes with 0.5% tigecycline, vehicle, or saline every 15 min for 3 h. EFFICACY Thirty-two rabbits were intrastromally injected with 700 Colony Forming Units (CFU) of MRSA in both eyes and were separated into 4 groups (n = 8): tigecycline 0.5%; vancomycin 5%; saline; and no treatment (euthanized before treatment for baseline CFU). Four hours after MRSA challenge, topical treatment of 1 drop every 15 min for 5 h was initiated. One hour after treatment, the corneas were harvested for CFU. The data were analyzed nonparametrically. RESULTS In vitro: Tigecycline demonstrated lower MICs than the other tested antibiotics against gram-positive organisms, especially MRSA, while MICs against gram-negative pathogens, including fluoroquinolone-resistant P. aeruginosa, appeared to be in the treatable range with aggressive topical therapy. TOLERABILITY 0.5% tigecycline was graded as minimally irritating. EFFICACY 0.5% tigecycline and vancomycin produced similar reductions in CFU and were less than saline (P < 0.05). Tigecycline and vancomycin demonstrated 99.9% reductions compared with baseline CFU. CONCLUSIONS Tigecycline is a potential candidate for a topical ocular antibiotic.
Collapse
Affiliation(s)
- Eric G Romanowski
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Tyler A Kowalski
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Katherine E O'Connor
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Kathleen A Yates
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Francis S Mah
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Robert M Q Shanks
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| | - Regis P Kowalski
- Department of Ophthalmology, The Charles T. Campbell Ophthalmic Microbiology Laboratory, University of Pittsburgh Medical Center and the UPMC Eye Center, Ophthalmology and Visual Science Research Center, Eye and Ear Institute, University of Pittsburgh School of Medicine , Pittsburgh, Pennsylvania
| |
Collapse
|
20
|
Hindley KE, Groth AD, King M, Graham K, Billson FM. Bacterial isolates, antimicrobial susceptibility, and clinical characteristics of bacterial keratitis in dogs presenting to referral practice in Australia. Vet Ophthalmol 2015; 19:418-26. [PMID: 26522379 DOI: 10.1111/vop.12325] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
OBJECTIVE To identify clinical characteristics, bacterial isolates, and their antimicrobial susceptibility patterns in a prospective study of dogs presenting with suspected bacterial keratitis to aid selection of appropriate therapy. ANIMALS Seventy-one client-owned dogs presenting to two referral hospitals in Australia. PROCEDURE Corneal swabs and clinical information were collected from dogs presenting with suspect bacterial keratitis from April 2012 to December 2014. Cytology and bacteriologic culture were performed on samples with in vitro antimicrobial susceptibility performed on bacterial isolates. RESULTS Positive cultures were obtained from 42 of the 71 ulcers sampled (59%), with 45 bacteria isolated. The most commonly isolated bacteria were β-hemolytic Streptococcus (14/45, 31%), Pseudomonas (14/45, 31%), and Staphylococcus species (8/45, 18%). β-Hemolytic Streptococcus spp. were resistant to neomycin, polymyxin B, gentamicin, framycetin and fusidic acid and >80% were resistant to ciprofloxacin but remained susceptible to chloramphenicol and cephalexin. Pseudomonas aeruginosa isolates were resistant to chloramphenicol, cephalexin, and fusidic acid; however, >90% were susceptible to ciprofloxacin, polymyxin B, and gentamicin. Brachycephalic breed (34/42, 81%), previous ocular surgery (15/42, 36%), prior use of a topical corticosteroid (13/42, 31%), and concurrent ocular surface disease (10/42, 24%) were common in dogs with bacterial keratitis. CONCLUSION Our study identified β-hemolytic Streptococcus and Pseudomonas spp. as the most common bacterial pathogens in canine bacterial keratitis presenting for referral. Many cases exhibited clinical factors known to influence corneal integrity that may predispose them to ulceration and infection. Based on in vitro antimicrobial susceptibility patterns and clinical outcomes, monotherapy with a fluoroquinolone may be ineffective in ulcers caused by β-hemolytic Streptococcus spp.
Collapse
Affiliation(s)
- Kate E Hindley
- Veterinary Ophthalmology, Small Animal Specialist Hospital, Lvl 1, 1 Richardson Place, North Ryde, 2113, NSW, Australia.
| | - Allyson D Groth
- Veterinary Ophthalmology, Small Animal Specialist Hospital, Lvl 1, 1 Richardson Place, North Ryde, 2113, NSW, Australia
| | - Martyn King
- Veterinary Ophthalmology, Rivergum Referral Services, Unit 1/26 Gympie Way, Willeton, 6155, WA, Australia
| | - Kathleen Graham
- Veterinary Ophthalmology, Small Animal Specialist Hospital, Lvl 1, 1 Richardson Place, North Ryde, 2113, NSW, Australia
| | - F Mark Billson
- Veterinary Ophthalmology, Small Animal Specialist Hospital, Lvl 1, 1 Richardson Place, North Ryde, 2113, NSW, Australia
| |
Collapse
|
21
|
EepR Mediates Secreted-Protein Production, Desiccation Survival, and Proliferation in a Corneal Infection Model. Infect Immun 2015; 83:4373-82. [PMID: 26324535 DOI: 10.1128/iai.00466-15] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 08/25/2015] [Indexed: 02/08/2023] Open
Abstract
Serratia marcescens is a soil- and water-derived bacterium that secretes several host-directed factors and causes hospital infections and community-acquired ocular infections. The putative two-component regulatory system composed of EepR and EepS regulates hemolysis and swarming motility through transcriptional control of the swrW gene and pigment production through control of the pigA-pigN operon. Here, we identify and characterize a role for EepR in regulation of exoenzyme production, stress survival, cytotoxicity to human epithelial cells, and virulence. Genetic analysis supports the model that EepR is in a common pathway with the widely conserved cyclic-AMP receptor protein that regulates protease production. Together, these data introduce a novel regulator of host-pathogen interactions and secreted-protein production.
Collapse
|
22
|
Kowalski RP. Is antibiotic resistance a problem in the treatment of ophthalmic infections? EXPERT REVIEW OF OPHTHALMOLOGY 2014. [DOI: 10.1586/eop.13.7] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
|
23
|
Abstract
PURPOSE To compare the intraocular penetration of 4 fluoroquinolone eye drops after topical instillation into rabbit eyes. METHODS The tested drugs were levofloxacin 1.5% (LVFX), gatifloxacin 0.3%, moxifloxacin 0.5% (MFLX), and besifloxacin 0.6% (BFLX). Forty-eight New Zealand white rabbits were randomly assigned into 2 groups. For group 1 (40 rabbits, 80 eyes), single instillation was performed, and tissue samples were acquired after 0.5, 1, 2, 4, and 6 hours. For group 2 (8 rabbits, 16 eyes), repeated instillation was performed (4 times, every 15 minutes), and tissues were acquired 1 hour after the fourth instillation. The drug concentrations in ocular tissues (cornea, aqueous, conjunctiva, and trisected vitreous) were analyzed with high-performance liquid chromatography. RESULTS The AUC 0-6 h (area under the curve, in microgram.hour/gram) in group 1 and the mean concentration (in micrograms/gram) in group 2 for LVFX, gatifloxacin 0.3%, MFLX, and BFLX, respectively, were 22.97, 6.44, 13.54, and 3.29 and 22.60, 6.99, 13.69, and 1.91 in cornea; 5.66, 1.43, 3.38, and 0.42 and 5.52, 1.29, 2.47, and 0.19 in aqueous humor; 2.33, 0.91, 2.17, and 9.83 and 4.51, 0.78, 1.48, and 2.09 in bulbar conjunctiva; 0.243, 0.051, 0.134, and 0.018 and 0.182, 0.055, 0.122, and 0.015 in anterior vitreous; none of the drugs achieved enough concentration in equatorial and posterior vitreous. Repeated instillation resulted in approximately 2.1 times greater penetration than single instillation. CONCLUSIONS LVFX and MFLX demonstrated good intraocular penetration particularly in cornea, aqueous humor, and anterior vitreous, and they may be considered the penetrative fluoroquinolones. BFLX showed high concentration in bulbar conjunctiva and may be considered the retentive fluoroquinolone.
Collapse
|
24
|
β-Catenin promotes host resistance against Pseudomonas aeruginosa keratitis. J Infect 2013; 67:584-94. [PMID: 23911965 DOI: 10.1016/j.jinf.2013.07.025] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2013] [Revised: 06/19/2013] [Accepted: 07/23/2013] [Indexed: 11/24/2022]
Abstract
OBJECTIVE To explore the role of β-catenin in Pseudomonas aeruginosa (PA) keratitis. METHODS Western-blot and immunostaining assay were used to determine the β-catenin protein expression in C57BL/6 (B6) corneas and in in vitro cultured murine cells including macrophage-like RAW264.7 cells, bone marrow-derived neutrophils and A6(1) corneal epithelial cells. B6 mice were subconjunctivally injected with lentivirus expressing active mutant of β-catenin (β-cat-lentivirus) vs appropriate control (Ctl-lentivirus), and then infected with PA. Pro-inflammatory cytokine levels were examined using real-time PCR and ELISA, and bacterial burden was assessed using plate count assays both in vivo and in vitro. RESULTS β-Catenin protein expression was decreased in B6 corneas, murine macrophage-like RAW264.7 cells, mouse bone marrow-derived neutrophils and mouse A6(1) corneal epithelial cells after PA infection. Over-expression of β-catenin in B6 corneas significantly reduced the severity of corneal disease after PA infection, by decreasing pro-inflammatory cytokine expression and bacterial burden. In vitro data further demonstrated that over-expression of β-catenin suppressed pro-inflammatory cytokine production but enhanced bacterial clearance in macrophages and neutrophils. CONCLUSIONS β-Catenin reduces the severity of PA keratitis by decreasing corneal inflammation and bacterial burden.
Collapse
|
25
|
Shanks RMQ, Lahr RM, Stella NA, Arena KE, Brothers KM, Kwak DH, Liu X, Kalivoda EJ. A Serratia marcescens PigP homolog controls prodigiosin biosynthesis, swarming motility and hemolysis and is regulated by cAMP-CRP and HexS. PLoS One 2013; 8:e57634. [PMID: 23469212 PMCID: PMC3585978 DOI: 10.1371/journal.pone.0057634] [Citation(s) in RCA: 40] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2012] [Accepted: 01/24/2013] [Indexed: 11/25/2022] Open
Abstract
Swarming motility and hemolysis are virulence-associated determinants for a wide array of pathogenic bacteria. The broad host-range opportunistic pathogen Serratia marcescens produces serratamolide, a small cyclic amino-lipid, that promotes swarming motility and hemolysis. Serratamolide is negatively regulated by the transcription factors HexS and CRP. Positive regulators of serratamolide production are unknown. Similar to serratamolide, the antibiotic pigment, prodigiosin, is regulated by temperature, growth phase, HexS, and CRP. Because of this co-regulation, we tested the hypothesis that a homolog of the PigP transcription factor of the atypical Serratia species ATCC 39006, which positively regulates prodigiosin biosynthesis, is also a positive regulator of serratamolide production in S. marcescens. Mutation of pigP in clinical, environmental, and laboratory strains of S. marcescens conferred pleiotropic phenotypes including the loss of swarming motility, hemolysis, and severely reduced prodigiosin and serratamolide synthesis. Transcriptional analysis and electrophoretic mobility shift assays place PigP in a regulatory pathway with upstream regulators CRP and HexS. The data from this study identifies a positive regulator of serratamolide production, describes novel roles for the PigP transcription factor, shows for the first time that PigP directly regulates the pigment biosynthetic operon, and identifies upstream regulators of pigP. This study suggests that PigP is important for the ability of S. marcescens to compete in the environment.
Collapse
Affiliation(s)
- Robert M. Q. Shanks
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh Eye Center, Pittsburgh, Pennsylvania, United States of America
| | - Roni M. Lahr
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh Eye Center, Pittsburgh, Pennsylvania, United States of America
| | - Nicholas A. Stella
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh Eye Center, Pittsburgh, Pennsylvania, United States of America
| | - Kristin E. Arena
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh Eye Center, Pittsburgh, Pennsylvania, United States of America
| | - Kimberly M. Brothers
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh Eye Center, Pittsburgh, Pennsylvania, United States of America
| | - Daniel H. Kwak
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Xinyu Liu
- Department of Chemistry, University of Pittsburgh, Pittsburgh, Pennsylvania, United States of America
| | - Eric J. Kalivoda
- Charles T. Campbell Laboratory of Ophthalmic Microbiology, Department of Ophthalmology, University of Pittsburgh Eye Center, Pittsburgh, Pennsylvania, United States of America
| |
Collapse
|
26
|
Animal models of bacterial keratitis. J Biomed Biotechnol 2011; 2011:680642. [PMID: 21274270 PMCID: PMC3022227 DOI: 10.1155/2011/680642] [Citation(s) in RCA: 41] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2010] [Revised: 11/29/2010] [Accepted: 12/09/2010] [Indexed: 11/20/2022] Open
Abstract
Bacterial keratitis is a disease of the cornea characterized by pain, redness, inflammation, and opacity. Common causes of this disease are Pseudomonas aeruginosa and Staphylococcus aureus. Animal models of keratitis have been used to elucidate both the bacterial factors and the host inflammatory response involved in the disease. Reviewed herein are animal models of bacterial keratitis and some of the key findings in the last several decades.
Collapse
|