Enterobacter endophthalmitis: Clinical settings, susceptibility profile, and management outcomes across two decades.

Purpose: To describe the clinical presentation and management of Enterobacter endophthalmitis and compare with previous in-house published literature. Methods: This was a retrospective interventional comparative case series involving 44 cases with culture proven Enterobacter endophthalmitis from April 2006 to August 2018 who underwent vitrectomy/vitreous biopsy, intravitreal antibiotics with or without additional procedures as appropriate. The current outcomes were compared to the outcomes previously reported a decade back from our center. The mean age at presentation, predisposing factor, number of interventions, interval between inciting event and presentation, type of intravitreal antibiotic used, anatomic, and the functional outcomes were analyzed and compared to the previous series. Results: There were 30 males. Mean age was 22.73 ± 21.35 years (median 14 years). Inciting event was open globe injury in 34 (77.27%) eyes, 4 (9.09%) eyes following cataract surgery, 3 (6.81%) eyes with endogenous endophthalmitis, 2 (4.54%) eyes following keratoplasty, and 1 eye (2.27%) following trabeculectomy. Presenting visual acuity was favorable (≥20/400) in 2 eyes (4.54%), at the final visit it was in 11 eyes (25%). The organisms were most sensitive to ciprofloxacin (95.12%), amikacin (90.47%), and ceftazidime (85.36%). A comparison of the current study with previous in-house study showed that number of eyes with presenting vision ≥20/400 as well as final vision ≥20/400 were comparable. Susceptibility was highest to ciprofloxacin 39 (95.12%) (previous series) and 33 (92%) (current series). Conclusion: Enterobacter organisms show susceptibility to ciprofloxacin, amikacin, and ceftazidime. Susceptibility profile, clinical presentations, and management remain largely similar over many years. Final outcome is unfavorable.

Does ophthalmic-grade silicone oil possess antimicrobial properties?

PURPOSE: To test the antimicrobial properties of silicon oil (Aurosil 1000 cSt, Aurosil Plus 5000 cSt) on in vitro growth of common microorganisms causing endophthalmitis. MATERIALS AND METHODS: Staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aeruginosa, multi-drug resistant (MDR) strain of Klebsiella pneumoniae, Escherichia coli, Candida albicans, and Aspergillus flavus were prepared to 0.5 McFarland turbidity. The bacteria and fungi were inoculated into the silicone oils, brain heart infusion (BHI) broth for bacteria and Sabouraud dextrose agar (SDA) broth for fungi, respectively, and cultured aerobically for 30 days. From each sample, 10 µl was plated onto nutrient agar and potato dextrose agar (PDA) for testing growth of bacteria and fungi respectively. Cultures from specimens, overnight incubation, and CFU counting were repeated on days 1, 3, 5, 7, 14, 21, 24, and 30. Negative controls were brain heart infusion and physiologic saline as well as silicone oils without any inoculations. RESULTS: All bacteria showed a decrease in CFUs by the fifth day and eliminated between 21 and 30 days in silicone oil. The silicon oil, irrespective of its viscosity, had only fungistatic effect up to 30 days. Colony-forming units of microorganisms remained stable in physiologic saline during the study. In BHI and Sabouraud broth, both bacteria and fungi showed a growth pattern that was compatible with the growth curve of microorganisms. CONCLUSION: Medical-grade silicone oil used in ophthalmology exhibited in vitro bactericidal and fungistatic activity over 30 days. Insertion of silicone oil in vitrectomy for endophthalmitis, when required, could supplement the antimicrobial activities of intravitreal antibiotics in management of endophthalmitis.

Microbiological Characteristics and Clinical Outcomes of Acinetobacter spp. Endophthalmitis with the First Reported Case of Acinetobacter haemolyticus Endophthalmitis.

AIM: To present the microbiological details and clinical outcomes of Acinetobacter spp. endophthalmitis with the first reported case of A. haemolyticus. METHODS: A retrospective study of microbiologically proven Acinetobacter spp. endophthalmitis was carried out from 2010 to 2015. The data collected included age, type of endophthalmitis, best-corrected visual acuity (BCVA), species involved, and antibiotic susceptibility pattern. The primary outcomes measured were anatomical outcomes in terms of globe integrity and functional outcome as BCVA at last follow-up. RESULTS: Eleven patients out of 3004 patients who underwent surgery for endophthalmitis were due to Acinetobacter spp. Seven cases (63.6%) were both smear and culture positive; there were two cases (18%) each of A. haemolyticus and A. baumanii. Four cases (36%) were only culture positive with negative smear. Three cases (27.2%) were polymicrobial. Ten cases (91%) were susceptible to amikacin and nine (82%) to ciprofloxacin. Six (54.5%) were resistant to ceftazidime. Mean logMAR BCVA improved to 1.8 (20/1330) from an initial 2.5 (20/6839). Pthisis bulbi was seen in two cases (18%). CONCLUSIONS: Even though the outcomes of Acinetobacter spp. endophthalmitis are modest to poor, outcomes following intervention are relatively good for A. haemolyticus. These cases have good susceptibility to amikacin, but are often resistant to ceftazidime.

Clinical features, microbiological profile and treatment outcome of patients with Corynebacterium endophthalmitis: review of a decade from a tertiary eye care centre in southern India.

AIMS: To report the clinical and microbiological profile along with treatment outcome of patients with endophthalmitis caused by Corynebacterium sp. METHODS: This is a retrospective, consecutive, non-comparative case series of patients with culture-proven Corynebacterium endophthalmitis seen between August 2004 and July 2014. RESULTS: Of 5439 patients clinically diagnosed as infective endophthalmitis, vitreous samples were culture positive for bacteria in 1488 (27%). Sixteen patients (1%) were identified as Corynebacterium endophthalmitis. The clinical settings included trauma (n=10), post-cataract surgery (n=5) and post-penetrating keratoplasty (n=1). In 7/16 (44%) patients, the organisms were visualised in direct microscopy. Tested by disc-diffusion method, all isolates were vancomycin sensitive. However, 9 of 10 isolates were resistant to ceftazidime and 5 of 14 isolates were resistant to amikacin. Initial treatment strategies included pars plana vitrectomy with intravitreal antibiotics (vancomycin and amikacin/ceftazidime) injection (n=9) and pars plana lensectomy along with pars plana vitrectomy and intravitreal antibiotics (vancomycin and amikacin/ceftazidime) injection (n=7). Final visual acuity was 20/200 or better in 11 (69%) of 16 patients. CONCLUSIONS: The prevalence of corynebacterial endophthalmitis is low. The organisms are susceptible to vancomycin, and early appropriate treatment results in favourable outcome.