Models of experimental pseudomonas keratitis: microbiological and clinical aspects

Annotation. Over the last ten years, there has been an increase in the incidence of bacterial keratitis caused by Pseudomonas aeruginosa, associated with contact lenses use. Certain features of the course of such keratitis, the mechanisms of corneal damage, the factors that affect the severity and depth of tissue destruction remain unclear. Therefore, the aim of our work was to model experimental pseudomonal keratitis in rabbits using different methods of infection and to investigate the microbiological and clinical aspects of keratitis depending on the method of infection. As a result of the study, we were able to reproduce superficial and deep keratitis with different methods of infection. Our proposed method cornea infection with bacterial films on a contact lens allowed to reproduce severe keratitis with a longer release of the pathogen from the surface of the affected cornea. It was also found that the results of microbiological examination of the material from the affected eye do not correlate with the course of severe keratitis: negative results of microbiological examination did not demonstrate the elimination of the pathogen from eye tissues, which deepens into corneal tissues, that was proved with microbiological examination of the cornea autopsy samples. These models of experimental keratitis can be used to study the pathomorphology, and pathophysiology of the keratitis caused by Pseudomonas aeruginosa, as well as to conduct experimental research of new antimicrobials and improve current guidelines for treatment of this pathology.

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Pseudomonas aeruginosa Keratitis: Protease IV and PASP as Corneal Virulence Mediators

Microorganisms ◽

10.3390/microorganisms7090281 ◽

2019 ◽

Vol 7 (9) ◽

pp. 281 ◽

Cited By ~ 4

Author(s):

Richard O’Callaghan ◽

Armando Caballero ◽

Aihua Tang ◽

Michael Bierdeman

Keyword(s):

Pseudomonas Aeruginosa ◽

Contact Lenses ◽

Corneal Tissue ◽

Deficient Mutant ◽

Interleukin 22 ◽

Mammalian Lung ◽

Corneal Damage ◽

Extensive Degradation ◽

Protease Iv

Pseudomonas aeruginosa is a leading cause of bacterial keratitis, especially in users of contact lenses. These infections are characterized by extensive degradation of the corneal tissue mediated by Pseudomonas protease activities, including both Pseudomonas protease IV (PIV) and the P. aeruginosa small protease (PASP). The virulence role of PIV was determined by the reduced virulence of a PIV-deficient mutant relative to its parent strain and the mutant after genetic complementation (rescue). Additionally, the non-ocular pathogen Pseudomonas putida acquired corneal virulence when it produced active PIV from a plasmid-borne piv gene. The virulence of PIV is not limited to the mammalian cornea, as evidenced by its destruction of respiratory surfactant proteins and the cytokine interleukin-22 (IL-22), the key inducer of anti-bacterial peptides. Furthermore, PIV contributes to the P. aeruginosa infection of both insects and plants. A possible limitation of PIV is its inefficient digestion of collagens; however, PASP, in addition to cleaving multiple soluble proteins, is able to efficiently cleave collagens. A PASP-deficient mutant lacks the corneal virulence of its parent or rescue strain evidencing its contribution to corneal damage, especially epithelial erosion. Pseudomonas-secreted proteases contribute importantly to infections of the cornea, mammalian lung, insects, and plants.

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Evaluation of the Carba NP Test for Rapid Detection of Carbapenemase-Producing Enterobacteriaceae and Pseudomonas aeruginosa

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00878-13 ◽

2013 ◽

Vol 57 (9) ◽

pp. 4578-4580 ◽

Cited By ~ 147

Author(s):

Nathalie Tijet ◽

David Boyd ◽

Samir N. Patel ◽

Michael R. Mulvey ◽

Roberto G. Melano

Keyword(s):

Pseudomonas Aeruginosa ◽

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Rapid Detection ◽

False Negative ◽

Bacterial Extract ◽

Content Type ◽

Negative Results ◽

False Negative Results

ABSTRACTThe Carba NP test was evaluated against a panel of 244 carbapenemase- and non-carbapenemase-producingEnterobacteriaceaeandPseudomonas aeruginosaisolates. We confirmed the 100% specificity and positive predictive value of the test, but the sensitivity and negative predictive value were 72.5% and 69.2%, respectively, and increased to 80% and 77.3%, respectively, using a more concentrated bacterial extract. False-negative results were associated with mucoid strains or linked to enzymes with low carbapenemase activity, particularly OXA-48-like, which has emerged globally in enterobacteria.

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Efficacy of Ophthalmic Solutions to Detach Adhering Pseudomonas aeruginosa from Contact Lenses

Cornea ◽

10.1097/00003226-199805000-00010 ◽

1998 ◽

Vol 17 (3) ◽

pp. 293-300 ◽

Cited By ~ 14

Author(s):

Andrew S. Landa ◽

Henny C. van der Mei ◽

Gabriel van Rij ◽

Henk J. Busscher

Keyword(s):

Pseudomonas Aeruginosa ◽

Contact Lenses ◽

Ophthalmic Solutions

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Microbiological Examination of Bandage Soft Contact Lenses Used in Laser Refractive Surgery

Journal of Refractive Surgery ◽

10.3928/1081-597x-19981101-10 ◽

1998 ◽

Vol 14 (6) ◽

pp. 631-635

Author(s):

Efstathios T Detorakis ◽

Dimitrios S Siganos ◽

Vasilios M Houlakis ◽

Vasilios P Kozobolis ◽

Ioannis G Pallikaris

Keyword(s):

Refractive Surgery ◽

Contact Lenses ◽

Soft Contact ◽

Soft Contact Lenses ◽

Microbiological Examination ◽

Laser Refractive Surgery

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Characterization of the New Metallo-β-Lactamase VIM-13 and Its Integron-Borne Gene from a Pseudomonas aeruginosa Clinical Isolate in Spain

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00465-08 ◽

2008 ◽

Vol 52 (10) ◽

pp. 3589-3596 ◽

Cited By ~ 52

Author(s):

Carlos Juan ◽

Alejandro Beceiro ◽

Olivia Gutiérrez ◽

Sebastián Albertí ◽

Margalida Garau ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Pcr Amplification ◽

Class 1 Integron ◽

Negative Results ◽

New Variant ◽

Class B ◽

Class 1 ◽

Encoding Gene ◽

Good Agreement

ABSTRACT During a survey conducted to evaluate the incidence of class B carbapenemase (metallo-β-lactamase [MBL])-producing Pseudomonas aeruginosa strains from hospitals in Majorca, Spain, five clinical isolates showed a positive Etest MBL screening test result. In one of them, strain PA-SL2, the presence of a new bla VIM derivative (bla VIM-13) was detected by PCR amplification with bla VIM-1-specific primers followed by sequencing. The bla VIM-13-producing isolate showed resistance to all β-lactams (except aztreonam), gentamicin, tobramycin, and ciprofloxacin. VIM-13 exhibited 93% and 88% amino acid sequence identities with VIM-1 and VIM-2, respectively. bla VIM-13 was cloned in parallel with bla VIM-1, and the resistance profile conferred was analyzed both in Escherichia coli and in P. aeruginosa backgrounds. Compared to VIM-1, VIM-13 conferred slightly higher levels of resistance to piperacillin and lower levels of resistance to ceftazidime and cefepime. VIM-13 and VIM-1 were purified in parallel as well, and their kinetic parameters were compared. The k cat/K m ratios for the antibiotics mentioned above were in good agreement with the MIC data. Furthermore, EDTA inhibited the activity of VIM-13 approximately 25 times less than it inhibited the activity of VIM-1. VIM-13 was harbored in a class 1 integron, along with a new variant (Ala108Thr) of the aminoglycoside-modifying enzyme encoding gene aacA4, which confers resistance to gentamicin and tobramycin. Finally, the VIM-13 integron was apparently located in the chromosome, since transformation and conjugation experiments consistently yielded negative results and the bla VIM-13 probe hybridized only with the genomic DNA.

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In vitro deposition of lysozyme on etafilcon A and balafilcon A hydrogel contact lenses: Effects on adhesion and survival of Pseudomonas aeruginosa and Staphylococcus aureus

Contact Lens and Anterior Eye ◽

10.1016/j.clae.2005.06.003 ◽

2005 ◽

Vol 28 (3) ◽

pp. 113-119 ◽

Cited By ~ 40

Author(s):

Shangtong Zhang ◽

Roya N. Borazjani ◽

Joseph C. Salamone ◽

Donald G. Ahearn ◽

Sidney A. Crow ◽

...

Keyword(s):

Staphylococcus Aureus ◽

Pseudomonas Aeruginosa ◽

Contact Lenses ◽

And Staphylococcus Aureus

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Antimicrobial Activity of Ceftazidime-Avibactam Tested against Multidrug-Resistant Enterobacteriaceae and Pseudomonas aeruginosa Isolates from U.S. Medical Centers, 2013 to 2016

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01045-17 ◽

2017 ◽

Vol 61 (11) ◽

Cited By ~ 52

Author(s):

Helio S. Sader ◽

Mariana Castanheira ◽

Dee Shortridge ◽

Rodrigo E. Mendes ◽

Robert K. Flamm

Keyword(s):

Pseudomonas Aeruginosa ◽

Multidrug Resistant ◽

Drug Resistant ◽

Large Collection ◽

Content Type ◽

Negative Results ◽

Medical Centers ◽

Extensively Drug Resistant ◽

Genes Encoding

ABSTRACT The in vitro activity of ceftazidime-avibactam and many comparator agents was determined against various resistant subsets of organisms selected among 36,380 Enterobacteriaceae and 7,868 Pseudomonas aeruginosa isolates. The isolates were consecutively collected from 94 U.S. hospitals, and all isolates were tested for susceptibility by reference broth microdilution methods in a central monitoring laboratory (JMI Laboratories). Enterobacteriaceae isolates resistant to carbapenems (CRE) and/or ceftazidime-avibactam (MIC ≥ 16 μg/ml) were evaluated for the presence of genes encoding extended-spectrum β-lactamases and carbapenemases. Ceftazidime-avibactam inhibited >99.9% of all Enterobacteriaceae at the susceptible breakpoint of ≤8 μg/ml and was active against multidrug-resistant (MDR; n = 2,953; MIC50/90, 0.25/1 μg/ml; 99.2% susceptible), extensively drug-resistant (XDR; n = 448; MIC50/90, 0.5/2 μg/ml; 97.8% susceptible), and CRE (n = 513; MIC50/90, 0.5/2 μg/ml; 97.5% susceptible) isolates. Only 82.2% of MDR Enterobacteriaceae (n = 2,953) and 64.2% of ceftriaxone-nonsusceptible Klebsiella pneumoniae (n = 1,063) isolates were meropenem susceptible. Among Enterobacter cloacae (22.2% ceftazidime nonsusceptible), 99.8% of the isolates, including 99.3% of the ceftazidime-nonsusceptible isolates, were ceftazidime-avibactam susceptible. Only 23 of 36,380 Enterobacteriaceae (0.06%) isolates were ceftazidime-avibactam nonsusceptible, including 9 metallo-β-lactamase producers and 2 KPC-producing strains with porin alteration; the remaining 12 strains showed negative results for all β-lactamases tested. Ceftazidime-avibactam showed potent activity against P. aeruginosa (MIC50/90, 2/4 μg/ml; 97.1% susceptible), including MDR (MIC50/90, 4/16 μg/ml; 86.5% susceptible) isolates, and inhibited 71.8% of isolates nonsusceptible to meropenem, piperacillin-tazobactam, and ceftazidime (n = 628). In summary, ceftazidime-avibactam demonstrated potent activity against a large collection (n = 44,248) of contemporary Gram-negative bacilli isolated from U.S. patients, including organisms resistant to most currently available agents, such as CRE and meropenem-nonsusceptible P. aeruginosa.

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Effect of Tears and Tear Residues on Worn Etafilcon and Polymacon Disposable Contact Lenses on the Adhesion of Pseudomonas Aeruginosa

Lacrimal Gland, Tear Film, and Dry Eye Syndromes 2 - Advances in Experimental Medicine and Biology ◽

10.1007/978-1-4615-5359-5_109 ◽

1998 ◽

pp. 775-784

Author(s):

Miguel F. Refojo ◽

Fee-Lai Leong ◽

Marta Portolés

Keyword(s):

Pseudomonas Aeruginosa ◽

Contact Lenses

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Topical medication as an initial therapeutic option for protruding and non-protruding condylomata acuminata of the distal urethra

BMJ Case Reports ◽

10.1136/bcr-2021-243618 ◽

2021 ◽

Vol 14 (9) ◽

pp. e243618

Author(s):

Tomislav Mestrovic ◽

Mario Sviben ◽

Sanja Zember ◽

Domagoj Drenjancevic

Keyword(s):

Human Papillomavirus ◽

Therapeutic Option ◽

Condylomata Acuminata ◽

Genital Warts ◽

The Other ◽

Urethral Meatus ◽

Tissue Destruction ◽

Topical Medication ◽

Sexually Transmitted ◽

Current Guidelines

Genital warts (also known as condylomata acuminata) caused by the human papillomavirus (HPV) represent one of the most common sexually transmitted infections. Although they are usually found in the outer genital region, a small proportion of men can present with (often unrecognised) intraurethral warts, generally limited to the distal urethra and urethral meatus. This poses a treatment challenge not adequately addressed by the current guidelines. Here, we present two cases of low-risk HPV-positive patients with protruding and non-protruding condylomata acuminata of the distal urethra, which were treated successfully by using two different topical regimens (ie, a combination of policresulen and imiquimod for one patient and 5-fluorouracil monotherapy for the other). Although this type of management results in lower rates of tissue destruction and complications and may be given preference as an initial therapeutic option, additional prospective comparative clinical studies are needed to elucidate its potential in similar cases.

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