Research on bacteria isolated from ocular infections, their antibiotic susceptibility patterns and impact on selection of appropriate therapy.

Bacterial ocular infections represent a common public health problem affecting people of all age groups. These infections can lead to damage of ocular structures or even a loss of vision. The spectrum of isolated bacteria and their susceptibilities to antibiotics, however, shows geographical variabilities, which can affect the success of most empirically-administered antimicrobial therapies. The aim of this study was thus to analyse bacterial aetiology in culture-positive acute and chronic ocular infections and its antimicrobial susceptibility profile in a large cohort of patients in the Czech Republic. The study also focused on corynebacteria identification, particularly on the prevalence of Corynebacterium macginleyi. A total of 2500 bacterial isolates obtained from 2015 to 2020 in University Hospital Hradec Kralove were included in the study. A total of 2320 (92.8%) bacterial isolates were Gram-positive and 180 (7.2%) were Gram-negative. Staphylococcus aureus was the predominant pathogen, isolated from 15.3% of ocular infections, followed by Enterobacterales, Streptococcus pneumoniae and Haemophilus influenzae, isolated in 2.9%, 1.6% and 1.0%, respectively. Corynebacterium macginleyi was confirmed as the most prevalent species of corynebacteria. Most bacteria showed good susceptibility to fluoroquinolones, chloramphenicol, and aminoglycosides. Gram-positive bacteria were also susceptible to tetracycline. To conclude, this study presents a 5-year assessment of bacterial aetiology of ocular infections in the East Bohemian region. The survey showed clear differences in the susceptibilities of several bacteria to select antibiotics compared to studies from other geographical regions in Europe. This clearly shows that local surveillance of the aetiology and antimicrobial susceptibility of bacteria is essential for adequate empirical therapy of ocular infections.

Influence of gender on clinical presentation, management practices and outcomes of ocular syphilis.

Ocular syphilis is a re-emerging inflammatory eye disease with a clear gender imbalance, disproportionately affecting men. We investigated the impact of gender on the presentation, management practices and clinical outcomes of this condition. Data generated from a study of patients consecutively diagnosed with ocular syphilis who attended a subspecialist uveitis service at one of four hospitals in Brazil over a 30-month period were disaggregated for analysis by gender. Two-hundred and fourteen eyes (161 men and 53 women) of 127 patients (96 men and 31 women) were included. Posterior uveitis was the most common presentation in both men and women (80.1% vs. 66.7%, p > 0.05), but men were significantly more likely to have vitritis as a feature of their disease (49.4% versus 28.8%, p = 0.019). Three eyes of women had nodular anterior scleritis (p = 0.015). Men were more likely to undergo a lumbar puncture to assess for neurosyphilis (71.9% vs. 51.6%, p = 0.048), but men and women undergoing a lumbar puncture were equally likely to have a cerebrospinal fluid abnormality (36.2% vs. 25.0%, p = 0.393). All patients were treated with aqueous penicillin G or ceftriaxone, and there was a trend towards more men receiving adjunctive systemic corticosteroid treatment as part of their management (65.2% vs. 46.7%, p = 0.071). There were no significant differences in the age of presentation, bilaterality of disease, anatomical classification of uveitis, initial or final visual acuity, and rates of ocular complications between men and women. Our findings indicate that ocular syphilis has comparable outcomes in men and women, but that there are differences in the type of ocular inflammation and management practices between the genders.

Microbiology of acute bacterial dacryocystitis: a tertiary institutional experience in South Australia.

PURPOSE: To provide a comprehensive microbiological profile of bacterial dacryocystitis in South Australia. By identifying the specific microorganism and antibiotic susceptibility, this study intends to aid ophthalmologists in choosing appropriate empirical antibiotic therapies and development of evidence-based clinical guidelines. METHOD: A retrospective study was conducted at the Royal Adelaide Hospital (RAH) over five years (2018-2023) of patients with acute dacryocystitis. The study included 43 patients, and data encompassed demographic information, clinical presentation, microbiological analysis, management, and outcomes. Patients with chronic dacryocystitis were excluded. RESULTS: Among the 43 patients included in the study (female 28 (65%), mean age: 64 years old), the most common clinical features were pain (74%) and swelling (70%). Organisms were identified in 49% of patients, with the predominant bacteria being Staphylococcus aureus (42%), Streptococcus species (19%), and Escherichia coli (8%). Aggregatibacter species (8%), Morganella morganii (4%), Enterobacter cloaceae (4%), Hafnia alvei (4%), mixed anaerobes (4%), E coliforms (4%) and Pseudomonas aeruginosa (4%) were also identified. The most frequently prescribed empirical antibiotics were amoxicillin-clavulanic acid (50%), flucloxacillin (33%) and cefalexin (18%). CONCLUSION: The microbiological trends of acute dacryocystitis have largely remained consistent, with a predominance of Gram positive organisms. This is the most recent profile analysis of acute dacryocystitis in South Australia and will help form evidence-based clinical guidelines.

Endogenous bacterial endophthalmitis in an HIV patient with uncontrolled diabetes: A case of rare ocular complication.

Endogenous bacterial endophthalmitis (EE) is an intraocular infection with a poor prognosis. Timely diagnosis and prompt treatment are crucial to prevent vision loss. In this communication, we describe a case of EE caused by Streptococcus pyogenes (Group A Streptococcus [GAS]) in an HIV-positive patient with poorly controlled type 2 diabetes mellitus (DM). A 60-year-old man with a history of HIV and poorly controlled type 2 diabetes, presented with progressive blurry vision, left eye pain, redness, and headache. EE was diagnosed based on the clinical presentation and gram stain analysis of blood culture. Treatment with vitreous tap, intravitreal, topical antibiotics, and systemic antibiotics significantly improved the patient's symptoms. The case highlights the rarity of GAS as a causative agent of EE, particularly in patients with risk factors such as HIV infection and DM.

Clinical characteristics and outcomes of people living with HIV and ocular syphilis during the COVID-19 health emergency.

BACKGROUND: The global shift in healthcare during the COVID-19 pandemic led to challenges in the care of people living with HIV. METHODS: We conducted a retrospective study that aimed to delineate sociodemographic, clinical characteristics and outcomes, of people living with HIV diagnosed with ocular syphilis. RESULTS: Fifty-three people living with HIV were identified with ocular syphilis. Thirty-eight (71.6%) presented ocular symptoms. Twenty-three (43.3%) underwent lumbar puncture, 5 (9.4%) were positive for neurosyphilis. Forty-seven (88.6%) received treatment, 32 (68%) received standard treatment with aqueous crystalline penicillin G, and 15 (31.9%) were treated with alternative regimens due to the impossibility of hospitalization. Six (11.3%) individuals were lost to follow-up and/or did not receive treatment. Eighteen (56.2%) out of 32 individuals in the aqueous crystalline penicillin G group experienced serological response, 5 (15.6%) experienced treatment failure, and 9 (28.1%) were lost to follow-up. In the alternative therapy group, 12 out of 15 individuals (80%) experienced serological response. One (6.7%) experienced treatment failure, and 2 (13.3%) were lost to follow-up. CONCLUSIONS: During the COVID-19 health emergency in Mexico, alternative treatments for ocular syphilis demonstrated favorable clinical outcomes amid challenges in accessing hospitalization.

Secondary bacterial corneal infection caused by Myroides species in primary fungal keratitis.

A middle-aged male patient presented with a central corneal perforation in a deep stromal infiltrate in his left eye. An emergency therapeutic penetrating keratoplasty was performed. Microbiological evaluation of the corneal scraping specimen revealed septate fungal filaments on stains. However, culture reports after 24 hours from the scraping sample and the excised half corneal button showed growth of gram-negative bacilli. This pathogen was identified as an aerobic, non-fermentative, gram-negative, bacillus by conventional microbiology and confirmed as Myroides species by the VITEK 2 Compact system (bioMérieux, Marcy l'Etoile, France). Susceptibility to chloramphenicol was noted based on which the patient was treated with topical chloramphenicol 0.5%. No recurrence of the infection was noted. This is the first reported case of corneal infection with the Myroides species of bacteria which, heretofore, have been known to cause endocarditis and urinary tract infections.

Do not stumble over the same "stone" twice: a case series of endogenous endophthalmitis secondary to severe systemic diseases.

BACKGROUND: Endogenous endophthalmitis (EE) is a rare but highly destructive eye emergency secondary to systemic infection. Acute endophthalmitis can lead to irreversible vision impairment or even loss of the whole eye, unless being diagnosed and treated promptly. CASE PRESENTATION: This study reports three typical EE cases of endogenous endophthalmitis secondary to different severe systemic diseases. Patients were recruited from the Department of ophthalmology at Zhongnan hospital of Wuhan University and the Department of ophthalmology at the Second Affiliated Hospital of Fujian Medical University. Patients were followed up for up to 60 days. Among these cases, the eye symptoms is the initial manifestations while secondary to original different special systemic conditions. Patients have been treated under dynamically prompt response undergoing systemic treatment and eye treatment at the same time. Best corrected visual acuity were 20/40, 20/60 and light perception during follow-up evaluation. CONCLUSIONS: Our observation suggest that prompt identification and treatment could save patients' vision from EE.

Syphilitic scleritis and episcleritis: A review.

Scleritis and episcleritis are rare, but potentially sight-threatening forms of syphilis. To provide a full description of this neglected subset of ocular syphilis, we evaluated the English literature for reports of syphilitic scleritis and episcleritis, recording the demographics, clinical characteristics, serological data, management practices, treatment responses, and visual outcomes. Previously published descriptions of 44 patients with syphilitic scleritis (50 eyes) and 9 patients with syphilitic episcleritis (14 eyes) were identified. The predominant type of scleritis was anterior scleritis, accounting for 92.9% of cases, with nodular anterior scleritis being the most frequent subtype at 58.1%. Almost one-quarter of patients were co-infected with human immunodeficiency virus (HIV). Initial misdiagnosis was common and led to delays in initiating treatment with appropriate antibiotics. Visual outcomes were often good in both scleritis and episcleritis, irrespective of HIV infection status, although complications including scleral thinning, keratitis, and uveitis, along with permanent visual loss and an association with neurosyphilis, were reported. Response to antibiotic treatment was typically rapid, often within 1 week. With the rising global incidence of syphilis, testing patients with scleritis or episcleritis for this infectious disease is important to ensure prompt diagnosis and treatment for best ocular and systemic outcomes.

Nocardia keratitis after small incision lenticule extraction (SMILE).

We report the case of a female patient in her late 20s who visited the clinic with concerns about poor vision, redness, watering and a burning sensation in her left eye 2 weeks after undergoing a small incision lenticule extraction. She had no history of systemic illness or immunosuppressed status. On slit lamp examination, she was found to have corneal stromal infiltrates in the interface at multiple locations. Given the clinical diagnosis of microbial keratitis, corneal scraping of the interface infiltrate was performed and sent for microbiological examination revealing gram-positive, thin, beaded filaments that were acid-fast positive and later identified by growth in culture media as Nocardia species. This case was managed successfully with the use of topical amikacin and systemic trimethoprim-sulfamethoxazole with complete resolution of infection.

Microbial keratitis in Southern Malawi: a microbiological pilot study.

OBJECTIVE: Microbial keratitis (MK) is a significant cause of blindness in sub-Saharan Africa. We investigated the feasibility of using a novel corneal impression membrane (CIM) for obtaining and processing samples by culture, PCR and whole-genome sequencing (WGS) in patients presenting with suspected MK in Malawi. METHODS AND ANALYSIS: Samples were collected from patients presenting with suspected MK using a 12 mm diameter polytetrafluoroethylene CIM disc. Samples were processed using culture and PCR for Acanthamoeba, herpes simplex virus type 1 (HSV-1) and the bacterial 16S rRNA gene. Minimum inhibitory concentrations of isolates to eight antimicrobials were measured using susceptibility strips. WGS was used to characterise Staphylococcus aureus isolates. RESULTS: 71 eyes of 71 patients were included. The overall CIM isolation rate was 81.7% (58 positive samples from 71 participants). 69 (81.2%) of isolates were Gram-positive cocci. Coagulase-negative Staphylococcus 31.8% and Streptococcus species 14.1% were the most isolated bacteria. Seven (9.9%) participants were positive for HSV-1. Fungi and Acanthamoeba were not detected. Moxifloxacin and chloramphenicol offered the best coverage for both Gram-positive and Gram-negative isolates when susceptibility was determined using known antimicrobial first quartile concentrations and European Committee on Antimicrobial Susceptibility Testing breakpoints, respectively. WGS identified known virulence genes associated with S. aureus keratitis. CONCLUSIONS: In a resource-poor setting, a CIM can be used to safely sample the cornea in patients presenting with suspected MK, enabling identification of causative microorganisms by culture and PCR. Although the microbiological spectrum found was limited to the dry season, these preliminary results could be used to guide empirical treatment.

Choroidal and central macular thickness before and after treatment in post fever retinitis.

PURPOSE: To study the choroidal thickness (CT) and central macular thickness (CMT) in post-fever retinitis (PFR) and their correlation with visual acuity and treatment. METHODS: A retrospective, observational study of patients presenting with PFR from 2013 to 2021 and with spectral domain optical coherence tomography (SD-OCT) (Heidelberg®, SpectralisTM, Heidelberg, Germany) images were included. The CT and CMT were measured at presentation and at the final visit. The CT was measured subfoveally and at points 2000 µm superior, inferior, medial, and lateral from the fovea using the caliper tool. RESULTS: Seventy-nine eyes of 65 patients were included for this study. The mean age was 39.03 (±16.00) years with female preponderance of 53.84% (n = 35). Mean follow-up duration was 30 days. Mean CT at presentation and at follow-up was 254.12 µm and 241.51 µm, respectively. CT was decreased in majority of the eyes 67.1% (n = 53) from their baseline value. Mean CMTs at presentation and final visit were 454.8 µm and 223.7 µm, respectively. Best corrected visual acuity had a positive correlation with CMT (r = 0.340; P = 0.002) and negligible correlation with CT. A significant decrease in the mean CT was noted in patients who received doxycycline either alone or in combination with a steroid as compared to those who did not receive any treatment (P < 0.001). The significance of which is unknown presently. CONCLUSION: CMT has a greater role in determining the final visual outcome than CT. CT can be reduced post-treatment with no effect on vision.

An adaptive drug-releasing contact lens for personalized treatment of ocular infections and injuries.

This research introduces an innovative solution to address the challenges of bacterial keratitis and alkali burns. Current treatments for bacterial keratitis and alkali burns rely on the frequent use of antibiotics and anti-inflammatory eye drops. However, these approaches suffer from poor bioavailability and fluctuating concentrations, leading to limited efficacy and potential drug resistance. Our approach presents an adaptive drug-releasing contact lens responsive to reactive oxygen species (ROS) at ocular inflammation sites, synchronously releasing Levofloxacin and Diclofenac. During storage, minimal drug release occurred, but over 7 days of wear, the lens maintained a continuous, customizable drug release rate based on disease severity. This contact lens had strong antibacterial activity and biofilm prevention, effectively treating bacterial keratitis. When combined with autologous serum, this hydrophilic, flexible lens aids corneal epithelial regeneration, reducing irritation and promoting healing. In summary, this ROS-responsive drug-releasing contact lens combines antibacterial and anti-inflammatory effects, offering a promising solution for bacterial keratitis and alkali burns.

Efficacy of a Novel Antibiotic Drug Combination Toward Multidrug-Resistant Ocular Pathogens.

PURPOSE: Antimicrobial resistance is a global health threat, compounded by the reduction in the discovery of new antibiotics. A repurposed drugs-based approach could provide a viable alternative for the treatment of multidrug-resistant (MDR) bacterial infections. In this study, we sought to evaluate the in vitro efficacy of a novel drug combination, polymyxin B/trimethoprim (PT) + rifampin on MDR isolates from patients with bacterial keratitis in India. METHODS: Forty-three isolates, which included 20 Staphylococcus aureus , 19 Pseudomonas aeruginosa , 3 Pseudomonas stutzeri , and 1 Acinetobacter baumannii , were evaluated for their antibiotic resistance by minimum inhibitory concentration (MIC). Fractional Inhibitory Concentration Index (FICI) testing was performed to measure the antimicrobial impact of PT + rifampin in combination. RESULTS: Among S. aureus isolates, 100% were resistant to at least 1 antibiotic class, 12 (60%) were MDR, and 14 (70%) were classified as methicillin-resistant. Among the gram-negative isolates, >90% were classified as MDR. Fractional Inhibitory Concentration (FIC) testing revealed that PT + rifampin was effective in completely inhibiting growth of all isolates while also displaying additive or synergistic activity in approximately 70% of the strains. Mean FICI values were 0.753 ± 0.311 and 0.791 ± 0.369 for S. aureus and gram-negative isolates, respectively, and a >2-fold reduction in MIC was measured for both PT and rifampin when tested in combination versus alone. CONCLUSIONS: Our data demonstrate the ability of PT + rifampin to eliminate all isolates tested, even those conferring MDR, highlighting the promise of this drug combination for the treatment of bacterial keratitis.

In vivo assessment of antimicrobial activity and toxicity of repeated 1% povidone-iodine applications vs a single 5% povidone-iodine application.

PURPOSE: To demonstrate the noninferiority in antimicrobial effectiveness of thrice-repeated applications of 1% povidone-iodine (PI) compared with a single application of 5% PI on the ocular surface in vivo and to evaluate potential toxicity of PI to the corneal epithelium. SETTING: Department of Ophthalmology, Shaare Zedek Medical Center, Jerusalem, Israel. DESIGN: Prospective, randomized, double-blind study. METHODS: Patients randomly received either a single application of 5% PI or repeated irrigations of 1% PI on the ocular surface preoperatively. Bacterial colony counts were quantitatively analyzed by taking standardized conjunctival swabs before and after irrigation, and differences in bacterial colony counts were compared between the 2 groups. The presence of superficial punctate keratopathy was evaluated in all patients by the National Eye Institute grading system. RESULTS: The study comprised 102 eyes of 102 patients. Both 1% and 5% PI yielded a marked decrease in bacterial colonies compared with before application ( P < .001). The repeated application of 1% PI showed a significantly lower bacterial count compared with the single application of 5% PI ( P < .05) and resulted in significantly less damage to the corneal epithelium compared with a single 5% PI application ( P < .001). CONCLUSIONS: Preoperative repeated applications of 1% PI effectively eradicated ocular surface bacteria equal to that of 5% PI with a less deleterious effect on the corneal epithelium. Our findings suggest that 1% PI may be a promising alternative to 5% PI.

Q Fever-Associated Chorioretinitis.

Coxiella burnetii is the causative agent in Q fever, a zoonotic disease. Ocular manifestations of this disease are extremely rare and have been infrequently reported. In this report, we describe a rare case of chorioretinitis in a patient incompletely treated for Q fever. We highlight the unique ocular manifestation with multimodal imaging, and the importance of a thorough history and prompt and correct treatment of the disease with systemic therapy. [Ophthalmic Surg Lasers Imaging Retina 2024;55:412-414.].

Spectrum and antibiotic sensitivity of bacterial keratitis: a retrospective analysis of eight years in a Tertiary Referral Hospital in Southwest China.

Purpose: The objective of this study was to investigate the epidemiological characteristics, distribution of isolates, prevailing patterns, and antibiotic susceptibility of bacterial keratitis (BK) in a Tertiary Referral Hospital located in Southwest China. Methods: A retrospective analysis was conducted on 660 cases of bacterial keratitis occurring between January 2015 and December 2022. The demographic data, predisposing factors, microbial findings, and antibiotic sensitivity profiles were examined. Results: Corneal trauma emerged as the most prevalent predisposing factor, accounting for 37.1% of cases. Among these cases, bacterial culture results were positive in 318 cases, 68 species of bacteria were identified. The most common Gram-Positive bacteria isolated overall was the staphylococcus epidermis and the most common Gram-Negative bacteria isolated was Pseudomonas aeruginosa. Methicillin-Resistant Staphylococci accounted for 18.1% of all Gram-Positive bacteria. The detection rate of P. aeruginosa showed an increasing trend over time (Rs=0.738, P=0.037). There was a significant decrease in the percentage of Gram-Negative microorganisms over time (Rs=0.743, P=0.035). The sensitivity of Gram-Positive bacteria to linezolid, vancomycin, tigecycline, quinupristin/dalfopristin, and rifampicin was over 98%. The sensitivity rates of Gram-Negative bacteria to amikacin, meropenem, piperacillin/tazobactam, cefoperazone sodium/sulbactam, ceftazidime, and cefepime were all above 85%. In patients with a history of vegetative trauma, the possibility of BK should be taken into account in addition to the focus on fungal keratitis. Conclusion: The microbial composition primarily consists of Gram-Positive cocci and Gram-Negative bacilli. Among the Gram-Positive bacteria, S. epidermidis and Streptococcus pneumoniae are the most frequently encountered, while P. aeruginosa is the predominant Gram-Negative bacteria. To combat Gram-Positive bacteria, vancomycin, linezolid, and rifampicin are considered excellent antimicrobial agents. When targeting Gram-Negative pathogens, third-generation cephalosporins exhibit superior sensitivity compared to first and second-generation counterparts. As an initial empirical treatment for severe cases of bacterial keratitis and those unresponsive to fourth-generation fluoroquinolones in community settings, the combination therapy of vancomycin and tobramycin is a justifiable approach. Bacterial keratitis can be better managed by understanding the local etiology and antibacterial drug susceptibility patterns.

Clinical Features and Treatment Outcomes of Carbapenem-Resistant Pseudomonas aeruginosa Keratitis.

Importance: Evaluation of the microbiological diagnostic profile of multidrug-resistant Pseudomonas aeruginosa keratitis and potential management with rose bengal-photodynamic antimicrobial therapy (RB-PDAT) is important. Objective: To document the disease progression of carbapenemase-resistant P aeruginosa keratitis after an artificial tear contamination outbreak. Design, Setting, and Participants: This retrospective observation case series included 9 patients 40 years or older who presented at Bascom Palmer Eye Institute and had positive test results for multidrug-resistant P aeruginosa keratitis between January 1, 2022, and October 31, 2023. Main Outcomes and Measures: Evaluation of type III secretion phenotype, carbapenemase-resistance genes blaGES and blaVIM susceptibility to antibiotics, and in vitro and in vivo outcomes of RB-PDAT against multidrug-resistant P aeruginosa keratitis. Results: Among the 9 patients included in the analysis (5 women and 4 men; mean [SD] age, 73.4 [14.0] years), all samples tested positive for exoU and carbapenemase-resistant blaVIM and blaGES genes. Additionally, isolates were resistant to carbapenems as indicated by minimum inhibitory concentration testing. In vitro efficacy of RB-PDAT indicated its potential application for treating recalcitrant cases. These cases highlight the rapid progression and challenging management of multidrug-resistant P aeruginosa. Two patients were treated with RB-PDAT as an adjuvant to antibiotic therapy and had improved visual outcomes. Conclusions and Relevance: This case series highlights the concerning progression in resistance and virulence of P aeruginosa and emphasizes the need to explore alternative therapies like RB-PDAT that have broad coverage and no known antibiotic resistance. The findings support further investigation into the potential effects of RB-PDAT for other multidrug-resistant microbes.