Contact lenses (CL) have become an immensely popular means of vision correction, offering comfort to millions worldwide. However, the persistent issue of biofilm formation on lenses raises significant problems, leading to various ocular complications and discomfort. The aim of this review is to develop safer and more effective strategies for preventing and managing microbial biofilms on CL, improving the eye health and comfort of wearers. Taking these into consideration, the present study investigates the intricate mechanisms of biofilm formation, by exploring the interplay between microbial adhesion, the production of extracellular polymeric substances, and the properties of the lens material itself. Moreover, it emphasizes the diverse range of microorganisms involved, encompassing bacteria, fungi, and other opportunistic pathogens, elucidating their implications within lenses and other medical device-related infections and inflammatory responses. Going beyond the challenges posed by biofilms on CL, this work explores the advancements in biofilm detection techniques and their clinical relevance. It discusses diagnostic tools like confocal microscopy, genetic assays, and emerging technologies, assessing their capacity to identify and quantify biofilm-related infections. Finally, the paper delves into contemporary strategies and innovative approaches for managing and preventing biofilms development on CL. In Conclusion, this review provides insights for eye care practitioners, lens manufacturers, and microbiology researchers. It highlights the intricate interactions between biofilms and CL, serving as a foundation for the development of effective preventive measures and innovative solutions to enhance CL safety, comfort, and overall ocular health. Research into microbial biofilms on CL is continuously evolving, with several future directions being explored to address challenges and improve eye health outcomes as far as CL wearers are concerned.

Endophytic bacteria, living inside plants, are competent plant colonizers, capable of enhancing immune responses in plants and establishing a symbiotic relationship with them. Endophytic bacteria are able to control phytopathogenic fungi while exhibiting plant growth-promoting activity. Here, we discussed the mechanisms of phytopathogenic fungi control and plant growth-promoting actions discovered in some major groups of beneficial endophytic bacteria such as Bacillus, Paenibacillus, and Pseudomonas. Most of the studied strains in these genera were isolated from the rhizosphere and soils, and a more extensive study of these endophytic bacteria is needed. It is essential to understand the underlying biocontrol and plant growth-promoting mechanisms and to develop an effective screening approach for selecting potential endophytic bacteria for various applications. We have suggested a screening strategy to identify potentially useful endophytic bacteria based on mechanistic phenomena. The discovery of endophytic bacteria with useful biocontrol and plant growth-promoting characteristics is essential for developing sustainable agriculture.

In contrast to \"frank\" pathogens, like Salmonella entrocolitica, Shigella dysenteriae, and Vibrio cholerae, that always have a probability of disease, \"opportunistic\" pathogens are organisms that cause an infectious disease in a host with a weakened immune system and rarely in a healthy host. Historically, drinking water treatment has focused on control of frank pathogens, particularly those from human or animal sources (like Giardia lamblia, Cryptosporidium parvum, or Hepatitis A virus), but in recent years outbreaks from drinking water have increasingly been due to opportunistic pathogens. Characteristics of opportunistic pathogens that make them problematic for water treatment include: (1) they are normally present in aquatic environments, (2) they grow in biofilms that protect the bacteria from disinfectants, and (3) under appropriate conditions in drinking water systems (e.g., warm water, stagnation, low disinfectant levels, etc.), these bacteria can amplify to levels that can pose a public health risk. The three most common opportunistic pathogens in drinking water systems are Legionella pneumophila, Mycobacterium avium, and Pseudomonas aeruginosa. This report focuses on these organisms to provide information on their public health risk, occurrence in drinking water systems, susceptibility to various disinfectants, and other operational practices (like flushing and cleaning of pipes and storage tanks). In addition, information is provided on a group of nine other opportunistic pathogens that are less commonly found in drinking water systems, including Aeromonas hydrophila, Klebsiella pneumoniae, Serratia marcescens, Burkholderia pseudomallei, Acinetobacter baumannii, Stenotrophomonas maltophilia, Arcobacter butzleri, and several free-living amoebae including Naegleria fowleri and species of Acanthamoeba. The public health risk for these microbes in drinking water is still unclear, but in most cases, efforts to manage Legionella, mycobacteria, and Pseudomonas risks will also be effective for these other opportunistic pathogens. The approach to managing opportunistic pathogens in drinking water supplies focuses on controlling the growth of these organisms. Many of these microbes are normal inhabitants in biofilms in water, so the attention is less on eliminating these organisms from entering the system and more on managing their occurrence and concentrations in the pipe network. With anticipated warming trends associated with climate change, the factors that drive the growth of opportunistic pathogens in drinking water systems will likely increase. It is important, therefore, to evaluate treatment barriers and management activities for control of opportunistic pathogen risks. Controls for primary treatment, particularly for turbidity management and disinfection, should be reviewed to ensure adequacy for opportunistic pathogen control. However, the major focus for the utility\'s opportunistic pathogen risk reduction plan is the management of biological activity and biofilms in the distribution system. Factors that influence the growth of microbes (primarily in biofilms) in the distribution system include, temperature, disinfectant type and concentration, nutrient levels (measured as AOC or BDOC), stagnation, flushing of pipes and cleaning of storage tank sediments, and corrosion control. Pressure management and distribution system integrity are also important to the microbial quality of water but are related more to the intrusion of contaminants into the distribution system rather than directly related to microbial growth. Summarizing the identified risk from drinking water, the availability and quality of disinfection data for treatment, and guidelines or standards for control showed that adequate information is best available for management of L. pneumophila. For L. pneumophila, the risk for this organism has been clearly established from drinking water, cases have increased worldwide, and it is one of the most identified causes of drinking water outbreaks. Water management best practices (e.g., maintenance of a disinfectant residual throughout the distribution system, flushing and cleaning of sediments in pipelines and storage tanks, among others) have been shown to be effective for control of L. pneumophila in water supplies. In addition, there are well documented management guidelines available for the control of the organism in drinking water distribution systems. By comparison, management of risks for Mycobacteria from water are less clear than for L. pneumophila. Treatment of M. avium is difficult due to its resistance to disinfection, the tendency to form clumps, and attachment to surfaces in biofilms. Additionally, there are no guidelines for management of M. avium in drinking water, and one risk assessment study suggested a low risk of infection. The role of tap water in the transmission of the other opportunistic pathogens is less clear and, in many cases, actions to manage L. pneumophila (e.g., maintenance of a disinfectant residual, flushing, cleaning of storage tanks, etc.) will also be beneficial in helping to manage these organisms as well.

Pseudomonas can lead to peritoneal dialysis-associated peritonitis, which is characterized by a poor prognosis, such as a substantial failure rate and a high death rate. This study aimed to provide an overview of Pseudomonas peritonitis\'s clinical features, the regimens of antibiotic, antibiotic resistance, and outcomes in peritoneal dialysis (PD) patients. This study observed patients with Pseudomonas peritonitis in two large PD centers in South China from January 2008 to December 2022. The demographics, symptomatology, antibiotics regimens, resistance to common antibiotics, and clinical outcomes of all included patients were reviewed. A total of 3,459 PD patients were included, among them 57 cases of peritonitis caused by Pseudomonas, including 48 cases (84.2%) of Pseudomonas aeruginosa. The incidence rate of Pseudomonas peritonitis was 0.0041 episode per patient-year. Of them, 28.1% (16 cases) of the patients were accompanied by exit site infection (ESI), and all had abdominal pain and turbid ascites at the time of onset. The most commonly used antibiotic combination was ceftazidime combined with amikacin. Approximately 89% of Pseudomonas species were sensitive to ceftazidime, and 88% were sensitive to amikacin. The overall primary response rate was 28.1% (16 patients), and the complete cure rate was 40.4% (23 patients). There was no significant difference in the complete cure rate of peritonitis using three and other antibiotic treatment regimens (44.8% vs 46.4%; P = 0.9). The successful treatment group had higher baseline albumin level (35.9 ± 6.2; P = 0.008) and residual urine volume (650.7 ± 375.5; P = 0.04). Although the incidence of peritonitis caused by Pseudomonas was low, the symptoms were serious, and prognosis was very poor. Pseudomonas was still highly susceptible to first-line antibiotics currently in use against Gram-negative bacteria. Patients with successful treatment had higher albumin levels and higher urine output.
OBJECTIVE: Although the incidence of peritoneal dialysis-associated peritonitis caused by Pseudomonas is very low, it seriously affects the technique survival of peritoneal dialysis patients. However, there are few studies and reports on Pseudomonas peritonitis in the Chinese mainland area. Therefore, the purpose of this study is to describe the clinical characteristics, the regimens of antibiotic, drug resistance, and outcome of peritoneal dialysis patients in southern China in the past 15 years and summarize the clinical experience in the treatment of Pseudomonas peritonitis.

BACKGROUND: Pseudomonas otitidis belongs to the genus Pseudomonas and causes various infections, including ear, skin, and soft tissue infections. P. otitidis has a unique susceptibility profile, being susceptible to penicillins and cephalosporins but resistant to carbapenems, due to the production of the metallo-β-lactamase called POM-1. This revealed genetic similarities with Pseudomonas aeruginosa, which can sometimes lead to misidentification.
METHODS: We report the case of a 70-year-old Japanese male who developed cellulitis and bacteremia during chemotherapy for multiple myeloma. He was initially treated with meropenem, but blood culture later revealed gram-negative bacilli identified as P. otitidis using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS). Carbapenem resistance was predicted from previous reports; therefore, we switched to dual therapy with levofloxacin and cefepime, and favorable treatment results were obtained.
CONCLUSIONS: This is the first reported case of P. otitidis cellulitis and bacteremia in an immunocompromised patient. Carbapenems are typically used in immunocompromised patients and P. otitidis is often resistant to it. However, its biochemical properties are similar to those of Pseudomonas aeruginosa; therefore, its accurate identification is critical. In the present study, we rapidly identified P. otitidis using MALDI-TOF MS and switched from carbapenems to an appropriate antimicrobial therapy, resulting in a successful outcome.

Amphipathic compounds known as biosurfactants are able to reduce surface and interfacial tensions. These substances produced by microbial organisms perform the same functions as chemical surfactants with several enhancements, the most significant of which is biocontrol activity. Lipopeptide is one of the five biosurfactants from natural resources and is identified as the best alternative for chemical surfactants and the major topic of interest for both scientific and industrial communities due to their increasingly growing potential applications in biological and commercial fields. These are the biological compounds with very less toxicity level that increase their importance in the pesticide industry. In this article we summarize the structural diversity of the microbial lipopeptide biosurfactants and focus on their applications as biocontrol agents in plants, covering (1) an intensive study of the structural diversity of lipopeptide biosurfactants originated primarily by the Bacillus, Pseudomonas, Cyanobacteria, and Actinomycetes species is presented, (2) the comparative study of advantages and disadvantages of characterization techniques and physicochemical properties which have a major role in biocontrol activity of microbial lipopeptides, and (3) their wide range biocontrol applications as systemic resistance inducers against different plant diseases, resistance against phytopathogens by alteration of wettability of plant surfaces and antimicrobial activities of important bioactive lipopeptides produced from Bacillus strains.

BACKGROUND: Respiratory infections caused by Staphylococcus aureus and Pseudomonas aeruginosa are a major concern for cystic fibrosis (CF) patients due to increasing antibiotic resistance. Bacteriophages, which are viruses that selectively target and kill bacteria, are being studied as an alternative treatment for these infections. This systematic review evaluates the safety and effectiveness of bacteriophages for the treatment of CF-related infections caused by S. aureus and/or P. aeruginosa. We conducted a search for original, published articles in the English language up to March 2023. Studies that administered bacteriophages via intravenous, nebulised, inhaled, or intranasal routes were included, with no comparators required. In vitro and in vivo studies were eligible for inclusion, and only animal in vivo studies that utilised a CF transmembrane conductance regulator (CFTR) animal model were included. Bacteriophage treatment resulted in a decrease in bacterial load in both humans and animals infected with P. aeruginosa. Complete eradication of P. aeruginosa was only observed in one human subject. Additionally, there was a reduction in biofilm, improvement in resistance profile, and reduced pulmonary exacerbations in individual case reports. Evidence suggests that bacteriophage therapy may be a promising treatment option for CF-related infections caused by P. aeruginosa and S. aureus. However, larger and more robust trials are needed to establish its safety and efficacy and create necessary evidence for global legislative frameworks.

UNASSIGNED: Pseudomonas citronellolis is an unusual pathogen in humans and has not been extensively described in the scientific literature. Herein, we present a case of bacteremia and septic shock due to Pseudomonas citronellolis following Campylobacter species gastroenteritis in a patient with immunosuppression.
UNASSIGNED: An 80-year-old man with myeloproliferative disorder on ruxolitinib presented with several days of worsening abdominal pain, which rapidly developed into septic shock with multi-organ failure and explosive diarrhea. Gram-negative bacilli observed on Gram staining of his blood culture broth were later identified as Pseudomonas citronellolis and Bacteroides thetaiotaomicron . Repeated abdominal imaging revealed no evidence of intestinal perforation or megacolon. In addition, stool PCR was positive for Campylobacter species. His clinical course improved after 14 days of meropenem with complete resolution of his symptoms and organ failure.
UNASSIGNED: P. citronellolis is a rare infection in humans. We postulate that Janus Associated Kinase (JAK) inhibition in myeloproliferative disorders heightened this patient\'s risk of bacterial translocation and severe illness in the setting of Campylobacter gastroenteritis. P. citronellolis may be identified more frequently as a pathogen in humans as more advanced diagnostic technologies become increasingly available in clinical microbiology.

Mounting evidence indicates that habitats such as wastewater and environmental waters are pathways for the spread of antibiotic-resistant bacteria (ARB) and mobile antibiotic resistance genes (ARGs). We identified antibiotic-resistant members of the genera Acinetobacter, Aeromonas, and Pseudomonas as key opportunistic pathogens that grow or persist in built (e.g., wastewater) or natural aquatic environments. Effective methods for monitoring these ARB in the environment are needed to understand their influence on dissemination of ARB and ARGs, but standard methods have not been developed. This systematic review considers peer-reviewed papers where the ARB above were cultured from wastewater or surface water, focusing on the accuracy of current methodologies.
Recent studies suggest that many clinically important ARGs were originally acquired from environmental microorganisms. Acinetobacter, Aeromonas, and Pseudomonas species are of interest because their ability to persist and grow in the environment provides opportunities to engage in horizontal gene transfer with other environmental bacteria. Pathogenic strains of these organisms resistant to multiple, clinically relevant drug classes have been identified as an urgent threat. However, culture methods for these bacteria were generally developed for clinical samples and are not well-vetted for environmental samples. The search criteria yielded 60 peer-reviewed articles over the past 20 years, which reported a wide variety of methods for isolation, confirmation, and antibiotic resistance assays. Based on a systematic comparison of the reported methods, we suggest a path forward for standardizing methodologies for monitoring antibiotic resistant strains of these bacteria in water environments.

Background: Gram-negative bacteria are causative agents of endogenous endophthalmitis (EBE). We aim to systematically review the current literature to assess the aetiologies, risk factors, and early ocular lesions in cases of Gram-negative EBE. Methods: All peer-reviewed articles between January 2002 and August 2022 regarding Gram-negative EBE were included. We conducted a literature search on PubMed and Cochrane Controlled Trials. Results: A total of 115 studies and 591 patients were included, prevalently Asian (98; 81.7%) and male (302; 62.9%). The most common comorbidity was diabetes (231; 55%). The main aetiologies were Klebsiella pneumoniae (510; 66.1%), Pseudomonas aeruginosa (111; 14.4%), and Escherichia coli (60; 7.8%). Liver abscesses (266; 54.5%) were the predominant source of infection. The most frequent ocular lesions were vitreal opacity (134; 49.6%) and hypopyon (95; 35.2%). Ceftriaxone (76; 30.9%), fluoroquinolones (14; 14.4%), and ceftazidime (213; 78.0%) were the most widely used as systemic, topical, and intravitreal anti-Gram-negative agents, respectively. The most reported surgical approaches were vitrectomy (130; 24.1%) and evisceration/exenteration (60; 11.1%). Frequently, visual acuity at discharge was no light perception (301; 55.2%). Conclusions: Gram-negative EBEs are associated with poor outcomes. Our systematic review is mainly based on case reports and case series with significant heterogeneity. The main strength is the large sample spanning over 20 years. Our findings underscore the importance of considering ocular involvement in Gram-negative infections.