Ocular delivery of Amphotericin B: current challenges and future perspectives

INTRODUCTION

Amphotericin B is a polyene antibiotic that is used as an off-label eye drop to treat fungal keratitis. Poor solubility, permeability and high susceptibility to hydrolytic degradation make it challenging to formulate a drug delivery system. Despite its drawbacks, it is a potent antifungal drug against Candida and other fungal species. However, it has not been explored much in ocular drug delivery. Hence, this review brings into focus the potential and increasing significance of Amphotericin B in ocular drug delivery.

AREAS COVERED

In this review, we have systematically summarized the use of Amphotericin B in ocular diseases, the various formulation challenges for Amphotericin B, along with its off-label ocular usage, and stability concerns. The degradation mechanism of Amphotericin B in different conditions was discussed in this article as well.

EXPERT OPINION

In the last few decades, several nanocarriers have been explored to improve the formulation challenges associated with Amphotericin B. Also, due to insufficient clinical studies and unknown toxicity profile, there is no US Food and Drug Administration (FDA) approved Amphotericin B formulation for ocular drug delivery. This review aims to offer thorough information about Amphotericin B in ocular drug delivery.

The antibiotic resistance profiles of Pseudomonas aeruginosa in the Asia Cornea Society Infectious Keratitis Study

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.

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.

Impact of digital cataract workflow on time and resource efficiencies in cataract surgery: time and motion study

PURPOSE

To compare time and resource-saving with integration of digital cataract workflow to the existing workflow in high-volume cataract surgery clinics.

SETTING

L V Prasad Eye Institute, Hyderabad, India (Site 1) and Narayana Nethralaya, Bengaluru, India (Site 2).

DESIGN

Prospective, time-and-motion.

METHODS

The total time to complete each step (preoperative measurements, surgical planning, and surgical procedures) of the cataract workflow, number of data fields entered, and support staff required for both workflows were recorded. All study measurements were determined first for existing EMR cataract workflow followed by digital workflow (integrated data management system with data reviewer, surgical planner, and data transfer to OR) at both sites.

RESULTS

A total of 85 (Site 1, 44; Site 2, 41) cataract workflows were analyzed. The integration of digital workflow into the site's existing EMR workflow reduced the mean time for preoperative measurements by 25.3% (P = .006), surgical planning by 55.1% (P = .008), and surgical procedures by 22.6% (P = .002). The mean±SD overall time for the surgery was significantly shorter in the digital group (887.3±103.3 vs 1271.3±300.7 seconds; P < .0001). For both sites, the number of data fields recorded and the number of support staff needed was significantly lesser for the digital workflow (P < .0001, for both).

CONCLUSIONS

Integration of digital workflow significantly reduced the overall cataract surgery time, variability of overall time, number of data fields recorded, and resource utilization. Complete digitalization has important implications for improving the efficiency and standardization of cataract surgery workflow.

Functionalized chitosan based antibacterial hydrogel sealant for simultaneous infection eradication and tissue closure in ocular injuries

Management of infections at ocular injury often requires prolonged and high dose of antibiotic, which is associated with challenges of antibiotic resistance and bacterial biofilm formation. Tissue glues are commonly used for repairing ocular tissue defects and tissue regeneration, but they are ineffective in curing infection. There is a critical need for antibacterial ocular bio-adhesives capable of both curing infection and aiding wound closure. Herein, we present the development of an imine crosslinked N-(2-hydroxypropyl)-3-trimethylammonium chitosan chloride (HTCC)‑silver chloride nanocomposites (QAm1-Agx) and poly-dextran aldehyde (PDA) based bactericidal sealant (BacSeal). BacSeal exhibited potent bactericidal activity against a broad spectrum of bacteria including their planktonic and stationary phase within a short duration of 4 h. BacSeal effectively reduced biofilm-embedded MRSA and Pseudomonas aeruginosa by ∼99.99 %. In ex-vivo human cornea infection model, BacSeal displayed ∼99 % reduction of ocular infection. Furthermore, the hydrogel exhibited excellent sealing properties by maintaining ocular pressure up to 75 mm-Hg when applied to human corneal trauma. Cytotoxicity assessment and hydrogel-treated human cornea with a retained tissue structure, indicate its non-toxic nature. Collectively, BacSeal represents a promising candidate for the development of an ocular sealant that can effectively mitigate infections and may assist in tissue regeneration by sealing ocular wounds.

Nanomicelles empower natamycin in treating fungal keratitis: An in vitro, ex vivo and in vivo study

Fungal infections of cornea are important causes of blindness especially in developing nations with tropical climate. However, the challenges associated with current treatments are responsible for poor outcome. Natamycin is the only FDA-approved antifungal drug to treat fungal keratitis, but unfortunately due to its poor water solubility, it is available as suspension. The marketed suspension (5% Natamycin) has rapid precorneal clearance, poor corneal permeability, a higher frequency of administration, and corneal irritation due to undissolved suspended drug particles. In our study, we developed clear and stable natamycin-loaded nanomicelles (1% Natcel) to overcome the above challenges. We demonstrated that 1% Natcel could permeate the cornea better than 5% suspension. The developed 1% Natcel was able to provide sustained release for up to 24 h. Further, it was found to be biocompatible and also improved the mean residence time (MRT) than 5% suspension in tears. Therefore, the developed 1% Natcel could be a potential alternative treatment for fungal keratitis.

Tetraspanin CD9-derived peptides inhibit Pseudomonas aeruginosa corneal infection and aid in wound healing of corneal epithelial cells

Pseudomonas aeruginosa is a leading cause of corneal infection both within India and globally, often causing a loss of vision. Increasing antimicrobial resistance among the bacteria is making its treatment more difficult. Preventing initial bacterial adherence to the host membrane has been explored here to reduce infection of the cornea. Synthetic peptides derived from human tetraspanin CD9 have been shown to reduce infection in corneal cells both in vitro, ex vivo and in vivo. We found constitutive expression of CD9 in immortalized human corneal epithelial cells by flow cytometry and immunocytochemistry. The synthetic peptides derived from CD9 significantly reduced bacterial adherence to cultured corneal epithelial cells and ex vivo human cadaveric corneas as determined by colony forming units. The peptides also significantly reduced bacterial burden in a murine model of Pseudomonas keratitis and lowered the cellular infiltration in the corneal stroma. Additionally, the peptides aided corneal wound healing in uninfected C57BL/6 mice compared to control mice. These potential therapeutics had no effect on cell viability or proliferation of corneal epithelial cells and have the potential to be developed as an alternative therapeutic intervention.

Assessment of CT perfusion indices of the clinicoradiological response to anti-tubercular therapy in patients with intestinal tuberculosis

AIM

To explore the possibility of using a novel technique, CT perfusion imaging, to monitor the response to anti-tubercular therapy (ATT) in patients with intestinal tuberculosis.

MATERIALS AND METHODS

A prospective observational study was performed in adults with treatment naive-intestinal tuberculosis. Clinical, endoscopic, and conventional radiological findings of patients were compared at baseline and post-ATT. CT perfusion imaging was performed with recording of six perfusion parameters (blood flow, blood volume, mean transit time, time to peak, maximum peak intensity, and permeability/blood flow extraction).

RESULTS

Twenty-two patients (13 women, 59%) with a median age of 25 years were recruited. The terminal ileum and ileocaecal junction were the most frequent sites of involvement (59%), with multiple segments of the intestine being involved in 16 patients (73%). Median duration of ATT was 6 months (range 6-10 months). Complete clinical response was observed in 22/22 (100%) patients, endoscopic response in 12/12 (100%) patients, and radiological response in 10/13 (76%) patients. There was a significant decrease in mean blood flow, blood volume, maximum peak intensity, and an increase in mean transit time and time to peak on follow-up CT perfusion imaging performed after 6 months of ATT.

CONCLUSION

Significant alterations in CT perfusion parameters were demonstrated following treatment, consistent with a decline in inflammation and vascularity. CT perfusion imaging of the bowel is a novel means to assess the radiological response to ATT in intestinal tuberculosis, although at the cost of a higher dose of radiation exposure.

A survey of Asian Eye Institutions on perioperative antibiotic prophylaxis in cataract surgery

PURPOSE

To determine current institutional practice patterns for the use of perioperative antibiotics and other measures to prevent infection after cataract surgery in Asia.

METHODS

An online survey-based study of leading eye institutions in China, Hong Kong, India, Indonesia, Japan, Malaysia, Pakistan, Philippines, Singapore, South Korea, Taiwan, Thailand and Vietnam was conducted. The survey was administered to 26 representative key opinion leaders from prominent tertiary eye institutions that are also national academic teaching institutions in Asia. Survey responses were collated and anonymized during analysis.

RESULTS

All surveyed institutions used povidone iodine for the preoperative antiseptic preparation of the eye, with notable variations in the concentration of povidone iodine used for conjunctival sac instillation. Preoperative topical antibiotics were prescribed by 61.5% and 69.2% of institutions in low-risk and high-risk cases, respectively. Regarding the use of intra-operative antibiotics, 60.0% and 66.7% of institutions administered intracameral antibiotics in low-risk and high-risk patients, respectively. Postoperative topical antibiotics use patterns were generally very similar in low-risk and high-risk patients. Over half of the institutions (52.2% and 68.0% in low-risk and high-risk patients, respectively) also indicated prolonged postoperative use of topical antibiotics (> 2 weeks). Not all surveyed institutions had established policies/protocols for perioperative antibiotic use in cataract surgery, endophthalmitis surveillance, and/or a monitoring program for emerging antimicrobial resistance.

CONCLUSION

There are variations in antimicrobial prophylaxis approaches to preoperative, intra-operative and postoperative regimens in cataract surgery in Asia. More evidence-based research is needed to support the development of detailed guidelines for perioperative antibiotic prophylaxis to reduce postoperative infections.

Measurement of Direct-Photon Cross Section and Double-Helicity Asymmetry at sqrt[s]=510 GeV in p[over →]+p[over →] Collisions

We present measurements of the cross section and double-helicity asymmetry A_{LL} of direct-photon production in p[over →]+p[over →] collisions at sqrt[s]=510  GeV. The measurements have been performed at midrapidity (|η|<0.25) with the PHENIX detector at the Relativistic Heavy Ion Collider. At relativistic energies, direct photons are dominantly produced from the initial quark-gluon hard scattering and do not interact via the strong force at leading order. Therefore, at sqrt[s]=510  GeV, where leading-order-effects dominate, these measurements provide clean and direct access to the gluon helicity in the polarized proton in the gluon-momentum-fraction range 0.02<x<0.08, with direct sensitivity to the sign of the gluon contribution.

Trachipleistophora hominis: molecular characterization of a rare pathogen causing microsporidial stromal keratitis

The authors report the clinical and microbiological findings of a unique case of stromal keratitis caused by a rare microsporidium, Trachipleistophora hominis. This case of stromal keratitis was in a 49-year-old male with a history of COVID-19 infection and diabetes mellitus. Corneal scraping specimens revealed numerous microsporidia spores upon microscopic examination. PCR of the corneal button revealed the presence of T. hominis infection, which could be controlled by penetrating keratoplasty surgery. The graft was clear with no recurrence of infection until the last follow-up 6 weeks postsurgery. This is the first case of human stromal keratitis caused by this organism in a post-COVID infection, confirmed by molecular diagnosis.

Unmasking of systemic lupus erythematosus in a patient with hemophagocytic lymphohistiocytosis- macrophage activation syndrome (HLA-MAS) and diffuse alveolar hemorrhage

Hemophagocytic lymphohistiocytosis (HLH) is a hyperinflammatory syndrome caused by macrophages and cytotoxic T cells with aberrant activation. The primary (genetic) form, which is caused by mutations that affect lymphocyte cytotoxicity and immune regulation, is most prevalent in children, whereas the secondary (acquired) form is prevalent in adults. Secondary HLH is commonly caused by infections or cancers, but it can also be caused by autoimmune disorders, in which case it is known as macrophage activation syndrome (MAS; or MAS-HLH). A 25-year-old female presented with a high-grade fever that lasted for two weeks. His laboratory results revealed pancytopenia, neutropenia, hypertriglyceridemia, hypofibrinogenemia, and hyperferritinemia. Based on the clinical presentation and laboratory findings, a provisional diagnosis of HLH has been made. A HLH protocol was utilized to treat the patient. During the course of hospitalization, systemic lupus erythematosus (SLE) was identified as the underlying cause. She improved dramatically after receiving an immunosuppressive regimen of etoposide, cyclosporine, and dexamethasone according to HLH protocol-2004 with individualized modifications. The clinician should be aware that HLH may be the initial manifestation of underlying SLE. Early diagnosis and aggressive, individualized treatment are the key to improving outcomes.

Association of Single-Nucleotide Polymorphisms in Interleukin Genes with Microbial Keratitis in a South Indian Population

BACKGROUND

To examine the relationship between single-nucleotide polymorphisms (SNPs) in interleukin (IL) genes and keratitis and its clinical manifestations.

METHODS

SNPs in IL1B, IL6, CXCL8, IL10, and IL12B were analysed. Differences in frequencies of alleles, genotypes and haplotypes between cases and controls as well as associations between SNPs and clinical variables were calculated by χ2 tests with odds ratios.

RESULTS

The minor homologous genotype in IL1B rs16944 (p = 0.036; odds ratio (OR) = 2.063, 95% confidence interval (CI): 1.048-4.061) and CXCL8 rs4073 (p = 0.041; OR = 0.463, 95% CI: 0.224-0.956) and the heterologous genotypes in IL6 rs1800795 (p = 0.046; OR = 0.563, 95% CI: 0.326-0.972) and IL12B rs2569254 (p = 0.0446; OR = 0.557, 95% CI: 0.314-0.989) or rs730691 (p = 0.0051; OR = 0.451, 95% CI: 0.260-0.784) were associated with keratitis. The minor genotype of rs16944 was associated with severe infection (p = 0.046). The heterologous genotype in rs2569254 was associated with hospital admission, photophobia, and mode of contact lens wear (p ≤ 0.041). The heterologous genotype in rs730691 was associated with blurred vision, discharge, anterior chamber reaction, and mode of wear (p ≤ 0.047).

CONCLUSIONS

This study demonstrates that SNPs in IL1B and CXCL8 are associated with risk of developing keratitis. The study also found relationships between SNPs and clinical measures of keratitis. The potential for ethnic differences in frequency of SNPs and their association with keratitis should be followed up using different populations.

Embracing technology in cataract surgical training - The way forward

While ophthalmology as a surgical branch itself has evolved technologically with newer instruments, techniques and procedures; ophthalmic surgical training appears to have stagnated in terms of how it is delivered and how trainees' learning and performance are assessed. This collaborative editorial attempts to identify the lacunae in ophthalmic residency training and highlight how technological tools such as surgical simulators can be incorporated into ophthalmic training even in limited-resource settings with good results.

Post-myocardial infarction late diastolic left ventricular blood flow energetics are independently associated with left ventricular remodeling

Background

Post-myocardial infarction (MI) left ventricular (LV) remodeling emerges as a compensatory mechanism and leads to complex pathophysiological changes in LV blood flow hemodynamics. The interplay, if any, between LV blood flow energetics and remodeling remains unknown. We hypothesized that LV blood flow energetics early after MI are independently related to the temporal changes in LV end-diastolic volume (LVEDV).

Methods

In this prospective cohort study, 69 patients with acute re-perfused ST-segment elevation MI (STEMI) were included. The patients underwent cardiovascular magnetic resonance (CMR) examination within 2 days of the index event and at 3-month. CMR examination included cine, late gadolinium enhancement, and whole-heart 4D flow acquisitions. LV volume-function, infarct size (indexed to body surface area), microvascular obstruction (MVO), mitral inflow, and 4D blood flow kinetic energy (KE) characteristics were obtained. LV mean and peak KEi (indexed to LVEDV) were quantified for all time parameters (entire cardiac cycle, during systole/diastole, at E- and A-waves).

Results

In univariable linear regression analysis, peak KEi (R-R interval), mean systolic KEi, A-wave KEi, MVO presence were all associated with the relative change (%) of LVEDV (p=0.03, p=0.01, p&lt;0.01, P=0.03, respectively). In multivariable linear regression analysis, A-wave KEi was identified as the only independent marker for association with the relative change of LVEDV (p=0.02). In another univariable linear regression analysis, A-wave KEi, infarct size, and MVO presence were all associated with the absolute change of LVEDV (p=0.03, p=0.04, p=0.04, respectively). In multivariable linear regression analysis, A-wave KEi was determined as the only independent marker for association with the absolute change of LVEDV (p=0.02). No significant association was observed between mitral inflow characteristics and relative and absolute change of LVEDV.

Conclusion

Late diastolic LV blood flow energetics early after acute MI are independently associated with both absolute and relative longitudinal changes in LVEDV and may provide incremental value over infarct and mitral inflow characteristics to be associated with post-MI LV remodeling.

Funding Acknowledgement

Type of funding sources: Foundation. Main funding source(s): British Heart Foundation

S9.4a Ocular infections by melanized fungi Curvularia lunata and Lasiodiplodia theobromae: Antifungal susceptibility and clinical outcome

 

S9.4 Free oral presentations (late breaking), September 23, 2022, 4:45 PM - 6:15 PM

Purpose

To report antifungal susceptibility and clinical correlations in melanized fungal isolates of Curvularia lunata and Lasiodiplodia theobromae from ocular infections.

Methods

Antifungal susceptibility testing was performed by broth microdilution testing, following Clinical and Laboratory Standard Institute guidelines, of 17 C. lunata and 13 L. theobromae isolates from monomicrobial infections of microbial keratitis or fungal endophthalmitis patients. Isolates resistant to ≥2 classes of antifungals were considered as multidrug-resistant (MDR). The panel of antifungals tested were amphotericin B, natamycin, voriconazole, ketoconazole, fluconazole, itraconazole, posaconazole, and caspofungin.

Results

Voriconazole showed the highest susceptibility (83.3% isolates) followed by natamycin (80%), fluconazole (80%), itraconazole (76.7%), ketoconazole (70%), posaconazole, and caspofungin (66.7% each) and lastly amphotericin B (63.3%). For treatment, all patients received topical natamycin, and few received additional oral ketoconazole or intraocular voriconazole. MDR isolates led to the poorer clinical outcomes (P=.015) in patients. But natamycin resistance alone did not show unfavorable outcomes (P=.28), though this was the most frequent drug used topically in fungal ocular infections.

Conclusion

Melanized fungi causing ocular infections have varying susceptibility to different antifungal agents. Most effective drug as seen in vitro in our study, was voriconazole. Significant resistance to amphotericin B, which is the most common antifungal used in intravitreal injections, was noted. MDR isolates overall, had poorer clinical outcomes.

Early treatment of corneal abrasions and ulcers-estimating clinical and economic outcomes

Background

In low-and-middle income countries, corneal abrasions and ulcers are common and not always well managed. Previous studies showed better clinical outcomes with early presentation and treatment of minor abrasions, however, there have been no formal studies estimating the financial impact of early treatment of abrasions and ulcers compared to delayed treatment.

Methods

We used the LV Prasad Eye Institute's (LVPEI's) electronic health record system (eyeSmart) to estimate the impact of early presentation on clinical outcomes associated with abrasions and ulcers. 861 patients with corneal abrasion and 1821 patients with corneal ulcers were studied retrospectively, and 134 patients with corneal abrasion prospectively. A health economic model was constructed based on LVPEI cost data for a range of patient scenarios (from early presentation with abrasion to late presentation with ulcer).

Findings

Our findings suggest that delayed presentation of corneal abrasion results in poor clinical and economic outcomes due to increased risk of ulceration requiring more extensive surgical management, increasing associated costs to patients and the healthcare system. However, excellent results at low cost can be achieved by treatment of patients with early presentation of abrasions at village level health care centres.

Interpretation

Treatment of early minor corneal abrasions, particularly using local delivery of treatment, is effective clinically and economically. Future investment in making patients aware of the need to react promptly to corneal abrasions by accessing local healthcare resources (coupled with a campaign to prevent ulcerations occurring) will continue to improve clinical outcomes for patients at low cost and avoid complex and more expensive treatment to preserve sight.

Funding

This research was funded by the Medical Research Council, grant MR/S004688/1.

The quality of reporting in cardiac MRI artificial intelligence segmentation studies - a systematic review

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): This work was supported by an NIHR AI Award, AI_AWARD01706. This research was also funded in part, by the Wellcome Trust [Grant number 205188/Z/16/Z ].

Background

There has been a rapid increase in the number of Artificial Intelligence (AI) studies of cardiac MRI (CMR) segmentation. AI has huge potential to improve image analysis assessments. However, advancement and clinical translation in this field depend on researchers presenting their work in a transparent and reproducible manner.

Purpose

This systematic review aimed to evaluate the quality of reporting in AI studies involving CMR segmentation.

Methods

MEDLINE and EMBASE databases were searched for AI CMR segmentation studies on 18/11/2021. The flow of study inclusion is shown in Figure 1. Any AI method to segment any cardiac structure on CMR was eligible for inclusion. Each study was assessed for compliance with the Checklist for Artificial Intelligence in Medical Imaging (CLAIM).

Results

70 studies were included in the qualitative analysis. Studies were published between 2015 to 2021, with the majority (71%) published in 2020 and 2021. Most studies were performed in Europe (33%), China (27%) and the USA (26%). Short-axis sections were segmented in 70% of studies and most commonly included both ventricles (51%) or the left ventricle alone (30%). 20 different architecture implementations were represented. Figure 2 summarises the most relevant CLAIM domains to AI segmentation. The training sample eligibility criteria, demographics and clinical characteristics were not reported in 47% and 81% of studies, respectively. Ground truth annotations, source of the annotations and annotation tool were absent in 31%, 36% and 51% of studies respectively. Preprocessing steps and software libraries and packages used in training were not included in 27% and 24%. Details on the training approach including the number of models trained and method of selecting the final model were missing in 20% and 17% of the studies. Methods of validation or testing on external data, inter- and intra- rater variability and failure analysis were unreported in 57%, 63% and 74%, respectively.

Conclusion

This systematic review highlights important gaps in the AI literature of CMR studies. We identified key items missing in the dataset description, model development, validation and testing that limit the transparency, reproducibility and hence validity of published AI studies. This review may support closer adherence to established frameworks for reporting standards.

SGLT2 inhibitors in heart failure with preserved and reduced ejection fraction: a systematic review and meta-analysis

Funding Acknowledgements

Type of funding sources: None.

Background

Over the recent months, the scenery of the pharmacological treatment of heart failure has changed. Sodium-glucose co-transporter 2 inhibitors (SGLT2i) have become the protagonists, as trial after trial is revealing a prognostic benefit of their use for patients with heart failure (HF). While their clear advantage in heart failure with reduced ejection fraction (HFrEF) has resulted in the addition of SGLT2i in the most recent treatment guidelines 1, the magnitude of their impact in heart failure with preserved ejection fraction (HFpEF) is still debated. With the recent results of EMPEROR-Preserved trial shedding more light into this matter 2, concrete evidence is needed now more than ever to ascertain the role of SGLT2i in the management of HFpEF.

Aims

We performed a systematic review and meta-analysis to evaluate the role of SLGT2i in the management of patients with HF. More specifically, we performed a pre-specified subgroup analysis to assess the impact of this drug class in heart failure with reduced and preserved ejection fraction separately.

Methods

We conducted a systematic search of PubMed, Embase, Cochrane and Web of Science databases from inception to 15th of September. With the primary endpoint being hospitalisation for heart failure (HHF) or cardiovascular death (CVD), we identified 9,493 articles out of which 8 randomised controlled trials and 20,758 patients were included in the meta-analysis 2–9. The hazard ratios (HR) and 95% CI given in each study were used for the meta-analysis. A random-effects model with inverse-variance weights was used to combine the effect measures from all studies on a logarithmic scale. Statistical heterogeneity was assessed using the I² statistic. The statistical analyses were conducted using the Review Manager (RevMan) software (version 5.3. Copenhagen: The Nordic Cochrane Centre, The Cochrane Collaboration, 2014).

Results

The use of SGLT2i was associated with a significant reduction in HHF or CVD both for the patients with heart failure and EF&gt;40% (HR=0.78, 95%CI: 0.69, 0.87; I2 0%) and for the patients with heart failure and EF&lt;40% (HR=0.74, 95%CI: 0.68, 0.81; I2 0%), while for the total population SGLT2i reduced the risk of HHF or CV death by 25% (HR=0.75, 95%CI: 0.70, 0.81; I2 0%) (figure 1). Additionally, a prespecified subanalysis showed that in the specific cohort of patients with heart failure and EF&gt;50%, SGLT2i resulted in 23% lower risk of HHF or CV death (HR=0.77, 95%CI: 0.66, 0.91; I2 22%) (figure 2).

Conclusion

This meta-analysis provides robust evidence that SGLT2i appear to have a prognostic benefit across the spectrum of heart failure subgroups in terms of HHF or CV death. Further large-scale randomised trials examining the role of this drug class in the management of HFpEF would be extremely valuable and might transform the field of therapeutic strategies in this challenging clinical entity.

Mycobiomes of the Ocular Surface in Bacterial Keratitis Patients

Inflammation of the cornea is known as keratitis, and bacteria, fungi, protozoans, and viruses are the etiological agents of this disease. Delayed treatment of keratitis could result in loss of vision and, under certain severity conditions, the removal of an eye and its associated structures. In the current study, the ocular surface (conjunctiva and cornea) mycobiomes of individuals with bacterial keratitis were compared with the ocular mycobiome (conjunctiva) of healthy individuals, free of any ocular morbidity. Mycobiomes were generated through NGS approach using conjunctival swabs and corneal scrapings as the source of DNA from which ITS2 was amplified and sequenced, as a proxy to identify fungi. The results indicated significant changes in the alpha-diversity indices and in the abundance at the phylum and genera level. Hierarchical clustering using a heatmap showed that the mycobiomes were different. Furthermore, NMDS plots also differentiated the mycobiomes in the three cohorts, implying dysbiosis in the mycobiomes of the conjunctivae and corneal scrapings of bacterial keratitis individuals compared to control individuals. A preponderance of negative interactions in the hub genera in the conjunctival swabs of bacterial keratitis individuals compared to healthy controls further re-emphasized the differences in the mycobiomes. The dysbiotic changes at the genera level in conjunctivae and corneal scrapings of bacterial keratitis individuals are discussed with respect to their possible role in causing or exacerbating ocular surface inflammation. These results demonstrate dysbiosis in the ocular mycobiome in bacterial keratitis patients compared to healthy controls for the first time.