Pseudomonas aeruginosa Endophthalmitis: Clinical Outcomes and Antibiotic Susceptibilities

POSTINTRAVITREAL INJECTION AND POSTCATARACT EXTRACTION ENDOPHTHALMITIS VISUAL OUTCOMES BY ORGANISM: A SYSTEMATIC REVIEW AND META-ANALYSIS

PURPOSE

To compare visual outcomes of endophthalmitis following intravitreal injections (IVIs) and cataract extraction by causative organism.

METHODS

Searches in Cochrane Central Register of Controlled Trials, MEDLINE, and Embase identified articles reporting visual outcomes by causative organisms in post-IVI and cataract extraction endophthalmitis cases from January 2010 to February 2022. A random-effects meta-analysis compared visual improvement among endophthalmitis cases caused by causative organisms.

RESULTS

Eighty-five out of 3,317 retrieved studies were included. The highest degree of visual acuity improvement in both post-IVI and postcataract extraction endophthalmitis was seen in cases caused by coagulase-negative staphylococci, followed by gram-negative organisms and other gram-positive organisms such as streptococci and enterococci. Culture-negative cases showed more visual acuity improvement than culture-positive cases in post-IVI endophthalmitis. These results remained consistent when accounting for endophthalmitis treatment, IVI type, condition requiring IVI treatment, follow-up period, and initial preprocedural visual acuity.

CONCLUSION

Coagulase-negative staphylococci and gram-negative organisms show the most visual acuity improvement in both post-IVI and postcataract extraction endophthalmitis. Other gram-positive organisms such as streptococci and enterococci are associated with less visual improvement. This updated systematic review and meta-analysis revealed that the results of the Endophthalmitis Vitrectomy Study are consistent decades later despite advancements in surgical practices and the evolution of microorganisms over time.

Clinical settings, management and factors affecting outcomes in multi and extensively-drug resistant Pseudomonas endophthalmitis

PURPOSE

To report the clinical settings, management and factors affecting outcomes in multi-drug resistant (MDR) and extensively-drug resistant (XDR) Pseudomonas endophthalmitis.

SETTINGS

Retrospective, consecutive, non-comparative interventional case series. Cases of MDR and XDR Pseudomonas endophthalmitis from January 2012 to December 2020 treated at our tertiary eye care center were included. Data collected included clinical data, anatomic and functional outcome, isolated micro-organisms, and culture sensitivity.

RESULTS

This study included 29 eyes of 29 patients with MDR/XDR Pseudomonas endophthalmitis. Mean age at presentation was 60.27 ± 14.9 years (median 63). Commonest clinical setting was acute post-operative endophthalmitis in 27 cases (93.1%). Concurrent corneal infiltrate was present in 11 eyes (37.9%). Initial intervention in 19 eyes (65.5%) was vitrectomy, 2 of which underwent endoscopic pars plana vitrectomy. Mean number of interventions was 3.34 ± 1.44 (median 4). Mean follow up was 3.25 ± 3.07 months (median 2). Sensitivity to ceftazidime was 48.28%. All isolates were sensitive to colistin. Mean visual acuity at last follow up in logMAR was 2.64 ± 1.48 (median 3.5). Seven eyes (24.13%) were NPL (nil perception of light) at the last follow up. Two eyes (6.9%) underwent evisceration. Nine eyes (31.03%) had a favourable anatomic and functional outcome. Eyes without a corneal infiltrate at presentation were found to have a favourable anatomic and favourable functional outcome (OR 11.91, P < 0.04, CI 1.08 to 130.93).

CONCLUSION

Corneal involvement at presentation is associated with poorer outcomes in MDR and XDR Pseudomonas endophthalmitis. There is a potential role of higher newer antibiotics especially colistin in the management of these cases.

Gram-Negative Endogenous Endophthalmitis: A Systematic Review

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.

Temporal Transcriptome Analysis Suggests Modulation of Key Pathways and Hub Genes in a Mice Model of Multi-Drug Resistant (MDR) Pseudomonas aeruginosa Endophthalmitis

PURPOSE

Increasing incidence of multidrug-resistant Pseudomonas aeruginosa (MDR-PA) causing endophthalmitis challenges our ability to manage this vision-threatening condition. In this study, temporal dynamics of immune response in a mouse model of MDR-PA endophthalmitis was investigated by whole transcriptome analysis.

METHODS

C57BL/6 mice were infected with MDR-PA and antibiotic susceptible (S-PA) clinical strains and disease severity were monitored at 6 and 24-h postinfection (p.i), following which eyeballs were enucleated. Microarray analysis was performed using SuperPrint G3 Mouse Gene Expression v2 chip and the differential gene expression analysis was performed with limma package in R (v4.0.0.)/Bioconductor (v3.11).

RESULTS

Histopathological analysis revealed a significant difference in retinal architecture and vitreous infiltrates at 6 and 24 h. In comparison to S-PA, MDR-PA revealed altered expression of 923 genes at 6 h and 2220 genes at 24 h. Further, 23 and 76% of these altered genes and its downstream interacting proteins showed time-specific expression (6 and 24 h respectively), indicating their association with disease progression. At 24 hours, MDR-PA induced endophthalmitis showed aberrant immune response with the enrichment inflammasome signalling, dysregulated ubiquitination, complement cascade, MMPs NF-κβ and IL-1 signalling.

CONCLUSION

The rapid development of transcriptional differences between the two-time points reveals that distinct genes contribute to disease severity. The results from this study highlighted a link between innate and adaptive immune responses and provided novel insights in the pathogenesis of MDR-PA endophthalmitis by extending the number of molecular determinants and functional pathways that underpin host-associated damage.

Endophthalmitis Caused by Pseudomonas aeruginosa: Clinical Characteristics, Outcomes, and Antibiotics Sensitivities

Purpose

The aim of this study is to report the clinical characteristics, visual outcomes, and antibiotic susceptibilities of patients with Pseudomonas aeruginosa endophthalmitis.

Methods

The medical records of patients with culture-proven Pseudomonas aeruginosa endophthalmitis treated from June 2013 to December 2019 were reviewed.

Results

This study included 36 eyes of 36 patients. The clinical settings included ocular trauma (15/36), corneal ulcer (9/36), postoperative endophthalmitis (5/36), endogenous (3/36), and unknown (4/36). Sixteen patients underwent evisceration, 13 patients underwent pars plana vitrectomy (PPV), 2 patients were treated with only intravitreal antibiotics, and 5 patients did not undergo surgery. Only one patient achieved a visual acuity of 20/400, and the others had all counting fingers or below. The cultured Pseudomonas aeruginosa was 100% sensitive to gentamicin, tobramycin, amikacin, ciprofloxacin, and levofloxacin and, approximately 95% sensitive to meropenem, imipenem, and aztreonam.

Conclusion

The visual outcomes of Pseudomonas aeruginosa endophthalmitis were very poor, and the evisceration rate remained high. Pseudomonas aeruginosa has good susceptibility to gentamicin, tobramycin, amikacin, ciprofloxacin, and levofloxacin.

Transcriptomic and Histological Analysis of Exacerbated Immune Response in Multidrug-Resistant Pseudomonas aeruginosa in a Murine Model of Endophthalmitis

Multidrug-resistant (MDR) endophthalmitis is a serious threat to the whole spectrum of therapeutic procedures associated with the risk of managing and preventing vision loss. We have earlier shown the interplay of immune mediators in patients with MDR Pseudomonas aeruginosa (PA) endophthalmitis leading to worse outcome. Expanding on these findings, a murine model of endophthalmitis was developed to explore the effects of drug resistance on the pathogenesis by analyzing the temporal changes in retinal morphology along with its transcriptomic signatures. Clinical isolates of susceptible (S-PA) and multidrug-resistant PA (MDR-PA) were injected intravitreally in C57BL/6 mice followed by enucleation at 6 and 24 h time points postinfection. Disease progression and retinal changes were monitored by clinical and histological assessment and transcriptome analysis in a pair-wise manner. Histological assessment of MDR-PA eyeball revealed higher disease severity (p < 0.05), CD45+ cells (p = 0.007), MPO+ cells (p = 0.01), GFAP+ (p = 0.02), along with higher retinal cell death in mice infected with MDR-PA (p = 0.008). Temporal transcriptome analysis revealed differential expression of nearly 923 genes at 6 h p.i. and 2,220 genes at 24 h p.i. (FC ≥2, adjusted p-value <0.05). Pathway enrichment analysis identified differential regulation of chemokine- and cytokine-mediated, MAPK, and NF-кβ signaling pathways. In conclusion, rapid deterioration of retinal architecture and immune exacerbation was significantly associated with the MDR endophthalmitis, suggesting the need for immunomodulatory agents to strengthen host cell functions and support antibiotics to save the retinal structure from inevitable deterioration and restoration of the vision.

Does Endogenous Endophthalmitis Need a More Aggressive Treatment?

Topic: To focus on endogenous endophthalmitis management, particularly etiology-based medical and surgical therapy.Methods: Literature search of published studies from July 1990 to February 2019 on endogenous endophthalmitis available on PubMed was made without any language constraints.Results: A total of 78 articles were retrieved from 728 initially analyzed and 62 studies were included. Although the superiority of vitrectomy over tap and inject techniques is controversial, the most recent publications favor an early surgical approach for endogenous endophthalmitis. Vitrectomy is useful in severe cases complicated by marked vitreous opacity, retinal detachment, poor initial visual acuity, and more virulent pathogens. Oral or intravenous antibiotics are also necessary to treat systemic infection. Vitrectomy is superior to blood cultures in diagnosing the etiology of infection.Conclusions: Endogenous endophthalmitis is an important cause of visual acuity impairment. Prompt treatment with appropriate use of pharmacological or surgical therapy is mandatory to preserve visual function.Abbreviations: IOP: intra-ocular pressure; AIDS: acquired immune deficiency syndrome; EVS: endophthalmitis vitrectomy study; CEVE: complete and early vitrectomy for endophthalmitis.

Antibiotic sensitivity trends of pseudomonas endophthalmitis in a tertiary eye care center in South India: A 12-year retrospective study

Purpose:

To assess trends in antibiotic sensitivity of pseudomonas and compare multidrug resistance (MDR) between Pseudomonas endophthalmitis cases presenting in two consecutive 6-year time frames in a tertiary center in South India.

Methods:

This is a retrospective comparative series of all Pseudomonas endophthalmitis cases treated from June 2004 to May 2016. Microbiological culture results in all endophthalmitis patients were screened for pseudomonas. Positive cases in the initial 6 and final 6 years were compared for sensitivity to antibiotics and the proportion of MDR. MDR was defined as resistance to at least two different classes of antibiotics.

Results:

Pseudomonas accounted for 74 of 389 endophthalmitis cases (19%), 42 in initial 6 and 32 in final 6 years. Sensitivity to ciprofloxacin, ofloxacin, gatifloxacin, moxifloxacin, and ceftazidime was 85.7%, 82.9%, 76.5%, 76.9%, 88.1% up to 2010 which reduced to 75%, 59.4%, 68.8%, 56.3%, 56.3%, respectively, after 2010, being significant for ofloxacin (P = 0.0349) and ceftazidime (P = 0.0028). Susceptibility to amikacin, gentamicin, and tobramycin changed non-significantly from 83.3%, 43.9%, 47.6% to 71.9%, 61.3%, 61.3%, respectively. Twenty of 74 cases (27%) were MDR with 16.7% in first 6 years versus 40.6% in final 6 years. Postoperative MDR cases rose from 10.3% to 50% (P = 0.0048).

Conclusion:

This study shows rising resistance of Pseudomonas to fluoroquinolones, amikacin, and ceftazidime in endophthalmitis. MDR also showed an upward trend, particularly in postsurgical cases.

Pseudomonas aeruginosa: a clinical and genomics update

Antimicrobial resistance (AMR) has become a global medical priority that needs urgent resolution. Pseudomonas aeruginosa is a versatile, adaptable bacterial species with widespread environmental occurrence, strong medical relevance, a diverse set of virulence genes and a multitude of intrinsic and possibly acquired antibiotic resistance traits. P. aeruginosa causes a wide variety of infections and has an epidemic-clonal population structure. Several of its dominant global clones have collected a wide variety of resistance genes rendering them multi-drug resistant (MDR) and particularly threatening groups of vulnerable individuals including surgical patients, immunocompromised patients, Caucasians suffering from cystic fibrosis (CF) and more. AMR and MDR especially are particularly problematic in P. aeruginosa significantly complicating successful antibiotic treatment. In addition, antimicrobial susceptibility testing (AST) of P. aeruginosa can be cumbersome due to its slow growth or the massive production of exopolysaccharides and other extracellular compounds. For that reason, phenotypic AST is progressively challenged by genotypic methods using whole genome sequences (WGS) and large-scale phenotype databases as a framework of reference. We here summarize the state of affairs and the quality level of WGS-based AST for P. aeruginosa mostly from clinical origin.

Characterization of Pseudomonas aeruginosa isolates from patients with endophthalmitis using conventional microbiologic techniques and whole genome sequencing

Purpose

To demonstrate antibiotic susceptibility and genomic virulence factor profiles of Pseudomonas aeruginosa isolates from patients with culture-confirmed endophthalmitis.

Methods

Clinical isolates from patients diagnosed with pseudomonas endophthalmitis were included. Laboratory antibiotic susceptibility testing and whole genome sequencing was performed on all isolates.

Results

In the current study, 8 patients had vitreous culture-confirmed endophthalmitis due to P. aeruginosa. All isolates were multi-drug resistant but sensitive to ceftazidime and each fluoroquinolone tested. Whole genome sequencing revealed a total of 179 unique genes. The most common type of virulence genes included those involved in adherence and the secretion system. Seven of 8 (88%) isolates were of the cytoinvasive phenotype (exoST) and no isolates contained exoU.

Conclusions

P. aeruginosa associated endophthalmitis is often multi-drug resistant and demonstrates a variety of virulence factors with those involved in adherence and the secretion system being the most common.

Infectious endophthalmitis leading to evisceration: spectrum of bacterial and fungal pathogens and antibacterial susceptibility profile

Purpose

To describe the spectrum of bacterial and fungal pathogens in cases of endophthalmitis requiring evisceration and report their antimicrobial susceptibilities.

Methods

Retrospective, consecutive, and descriptive case series of endophthalmitis that underwent evisceration from January 2004 to December 2017. Vitreous samples from all patients had been investigated for bacteria and fungus using institutional protocol. Bacterial isolates were identified using analytical profile index (API) system until 2010 and Vitek-2 compact system (bioMérieux, France), thereafter. The susceptibility of bacterial isolates to a variety of antibiotics was determined by the Kirby-Bauer disk-diffusion method.

Results

Of 791 cases reviewed, culture positivity was reported in 388 cases (48.92%). Commonest clinical setting of endophthalmitis necessitating evisceration was post-microbial keratitis (58%), followed by post-trauma and post-cataract surgery (14–15%). The commonest isolate was Streptococcus pneumoniae, seen in 68 samples overall (17.52%). One hundred and eighty-three isolates (47.16%) were gram-positive, 86 (22.16%) were gram-negative, and fungi constituted 137 (35.3%) isolates. Streptococcus pneumoniae was the commonest gram-positive bacterial isolate seen in 68/183 samples (37.15%). Among gram-negative organisms, the commonest was Pseudomonas aeruginosa seen in 47/86 (54.65%). Aspergillus spp. formed the commonest fungal isolate, 58/137 (42.33%). The susceptibility of the gram-positive bacteria was highest with vancomycin, 136/147 (92.51%) and for gram-negative bacteria was seen best with imipenem 24/29 (82.75%). Susceptibility to ceftazidime was 31/61 (50.81%) in 31/61.

Conclusion

Endophthalmitis due to Pneumococci, Aspergillus, and Pseudomonas can be very fulminant and progress to require evisceration in spite of prompt and appropriate treatment.

Interventions and Outcomes in Patients with Infectious Pseudomonas scleritis: A 10-Year Perspective

Purpose: To identify interventional factors associated with improved visual results and faster time to resolution for patients with Pseudomonas scleritis. Methods: Retrospective study analyzing inciting factors, therapeutic modalities, and outcomes of patients with Pseudomonas scleritis. Results: A total of 24 patients were analyzed; 22 were treated as outpatients. All had resolution of infection and 58% (n = 14) maintained ≥20/200 vision. Medical therapy included topical and oral antibiotics; seven received additional subconjunctival injections; two were admitted for IV antibiotics. Patients presenting with ≥20/200 vision were more likely to maintain this level of vision (n = 8, 80%) compared to those presenting with severe vision loss (n = 5, 36%) (p = 0.04). A similar proportion of patients who received (n = 8, 61%) and did not receive (n = 5, 39%) oral steroids achieved 20/200 vision or better once infection resolved, p = 1.0. Conclusions: Pseudomonas scleritis can be successfully managed in the outpatient setting. Oral steroids do not appear harmful in the treatment of this disease.