Intracameral Povidone-Iodine for Multidrug-Resistant Pseudomonas aeruginosa Exogenous Endophthalmitis: A Case Report and Literature Review Open Access

Exogenous endophthalmitis is a serious, sight-threatening condition that can result in irreversible blindness. Early interventions, such as pars plana vitrectomy (PPV) and\or empiric wide-spectrum intravitreal antibiotics, are administered to limit the extent of ocular damage. A wide range of pathogens can be responsible, with bacterial and fungal infections being the most common [1]. According to Relhan et al. [2], multidrug-resistant (MDR) organisms are becoming increasingly prevalent, significantly complicating the management of these cases. Therefore, there is an urgent need to explore novel therapeutic agents capable of targeting these resistant pathogens and mitigating their impact. Povidone-iodine (PI), also known as Betadine, is widely recognized as a potent microbicidal disinfectant with broad-spectrum activity against viruses, fungi, and MDR bacteria, making it a potential solution to address this therapeutic challenge [3]. In vitro, repeated intraocular injections of 0.05–0.5% of PI significantly inhibited the growth of various bacterial strains [4]. Clinically, a recent study showed that intraocular administration of 0.025% PI is both safe and effective in treating infectious endophthalmitis, including cases arising from both exogenous and endogenous causes [5]. Furthermore, frequent irrigation of the ocular surface with 0.250% PI every 20–30 s during ophthalmic surgeries eliminates conjunctival flora, which reduces bacterial translocation into the intraocular space and prevents endophthalmitis [6]. In this report, we present a case of exogenous endophthalmitis caused by MDR Pseudomonas aeruginosa successfully treated with intracameral injection of PI.

A 59-year-old male presented to the emergency department with a 1-day history of sudden pain and redness in his left eye (OS). The patient’s medical history included essential hypertension and hepatitis B. The patient has a history of multiple ophthalmic procedures all done elsewhere which included cataract surgery, retinal detachment repair with silicon oil tamponade followed a few months later by silicone oil removal in May 2024. Since he developed retinal re-detachment, another surgery with silicon oil reinjection was done in July 2024. At presentation in October 2024, the best corrected visual acuity was light perception only. He had eyelid swelling, severe conjunctival injection, chemosis, hazy cornea, a 2-mm hypopyon, severe inflammatory membranes covering the pupil, a round regular sluggish reactive pupil, high intraocular pressure of 30 mm Hg, posterior chamber intraocular lens, and a dim red reflex (Fig. 1a). The examination of the right eye (OD) was unremarkable. Based on the clinical appearance of the left eye, the diagnosis of exogenous endophthalmitis was made. Endogenous endophthalmitis was excluded since the patient did not have any constitutional symptoms. In addition, his systemic workup including blood and urine cultures, abdominal and liver US were negative for a systemic focus of infection. The patient underwent urgent aqueous and vitreous tap followed by anterior chamber washout and intravitreal injections of vancomycin (1 mg/0.1 mL) and ceftazidime (2.25 mg/0.1 mL). The patient was also started on IV ciprofloxacin (400 mg) q12 h. Any primary vitreoretinal intervention was not possible due to poor visibility caused by corneal edema.

On postoperative day one, the patient continued to experience symptoms, with a recurrence of severe inflammatory membranes in the anterior chamber (Fig. 1b). Gram stain from aqueous and vitreous samples showed Gram-negative rods, and culture of the samples taken revealed MDR Pseudomonas aeruginosa resistance to ceftazidime, cefepime, gentamicin, meropenem, and piperacillin/tazobactam. Given clinical worsening, the patient underwent a repeat anterior chamber washout, during which intracameral injection of 0.1 mL of PI (0.1%) was administered. From the following day, the patient started showing significant symptomatic and clinical improvement without recurrence of anterior chamber reaction or inflammatory membranes. The corneal edema improved, and the red reflex started returning from the 2nd day post-intracameral injection of 0.1% PI. Fundus examination showed an attached retina (Fig. 1c). His vision improved to 6/60. Three-month follow-up examination confirmed continued clinical stability and a visual acuity at 2/60 unaided with mild corneal edema. We followed the CARE Checklist as shown in the online supplementary material (for all online suppl. material, see https://doi.org/10.1159/000546659).

MDR Pseudomonas aeruginosa is a common pathogen in hospital-acquired infections, often limiting the available options for effective antimicrobial therapy [7]. In ophthalmology, 5% PI is widely used for antisepsis before ocular surgery and applied topically as a preoperative prophylactic agent with a minimum contact time of 3 min [8]. PI has demonstrated potential as an adjunctive treatment in cases of severe intraocular infections, particularly due to its broad-spectrum antimicrobial activity and low risk of inducing resistance [9]. Nevertheless, high concentrations of extraocular Betadine 5% have been shown to significantly decrease visual acuity, contrast sensitivity, along with increasing dry eye symptoms and corneal staining [10]. Also, it can lead to chemical burns and cytotoxic effects [11]. In this report, we present a successfully treated case of MDR Pseudomonas endophthalmitis with intracameral 0.1% PI.

To date, only a limited number of studies in the literature have reported the use of Betadine as an antiseptic regimen for the treatment of endophthalmitis. Comparing our case to the literature (Table 1), a significant emphasis emerges on the role of Betadine as an adjunctive treatment in managing infections, particularly those caused by MDR organisms. In our case, after the initial failure of intravitreal vancomycin and ceftazidime with documented resistance to ceftazidime, the introduction of PI led to dramatic clinical improvement and resolution of symptoms. This outcome underscores the efficacy of PI in targeting resistant pathogens, especially in cases where conventional antibiotics fall short. Nakashizuka et al. [5] incorporated PI into their treatment regimen for patients with exogenous and endogenous endophthalmitis, achieving favorable outcomes. Similarly, Liu et al. [12] reported the use of PI alongside intravenous cefoperazone + sulbactam. Tanaka et al. [13] also utilized PI effectively in a case of endogenous endophthalmitis, demonstrating its broad-spectrum antimicrobial properties. Moreover, Otani et al. [3] documented a successful outcome in an exogenous endophthalmitis case treated with PI without pars plana vitrectomy. In a small case series, 4 eyes with endophthalmitis underwent vitrectomy using 0.025% PI in balanced salt solution PLUS as the vitreous irrigating solution. All cases achieved resolution of the infection without ocular complications, accompanied by notable improvements in visual acuity [14]. This suggests that PI can be utilized across various clinical scenarios, including cases where vitrectomy is not feasible. All cases of endophthalmitis treated by PI reported no adverse effects, especially since the literature used a diluted dose of 0.01–0.1% [3, 5, 14]. The dose of intravitreal medications in silicone oil-filled eyes should be carefully considered. Hegazy et al. [15] reported that nontoxic concentrations of intravitreal drugs can cause toxicity in a silicone-filled eye. Other studies emphasize the critical need for careful consideration of standard intravitreal agent dosages, coupled with vigilant monitoring for potential side effects – essential factors that should be thoroughly discussed with patients [16]. A study conducted by Lee et al. [9] investigated the efficacy of intravitreal PI in treating vancomycin-resistant Enterococcus faecalis endophthalmitis in a rabbit model. The study included four treatment groups and one control group. Notably, group A, which received a PI concentration of 0.1%, demonstrated that even at low concentrations, PI was effective in treating vancomycin-resistant Enterococcus faecalis endophthalmitis. Based on these findings, we opted for the lowest concentration and closely monitored the patient’s response. The strength of this case report lies in its contribution to the limited literature on PI usage as a therapeutic agent for MDR endophthalmitis. The case highlights the efficacy of PI in a clinical setting where standard antibiotic therapy failed, reinforcing its potential as an alternative treatment. However, the current report has some limitations due to the lack of a larger number of clinical cases treated with this therapy, which could provide stronger evidence. Furthermore, larger comparative studies are recommended to evaluate the toxicity risk in the long term.

From the patient’s viewpoint, the treatment journey was marked by both hope and apprehension. While the promise of improved vision brought optimism, concerns about potential side effects and treatment efficacy remained. Clear communication from the medical team played a crucial role in alleviating fears, reinforcing the importance of shared decision-making in ophthalmic care.

In conclusion, our case and the other studies collectively underscore the critical importance of PI as an adjunctive therapeutic agent in the management of endophthalmitis, particularly in the context of increasing antimicrobial resistance. The dramatic clinical improvements observed in both our case and the studies highlight the need for further investigation into the mechanisms by which PI exerts its microbicidal effects, especially in MDR pathogens and its potential to enhance outcomes in patients with challenging infections.

Hamad Medical Corporation’s Ethical Committee reviewed and approved this study protocol (MRC/2025/08). Written informed consent was obtained from the patient for publication of the details of their medical case and any accompanying images.

All authors have no conflicts of interest.

Qatar National Library funded the publication of this article.

Fatma Kassem Mohamed, Mohamed S.I. Mohamed, and Hashem Abu Serhan wrote the manuscript and performed a literature review of the case reports. Maha M. El Shafei and Anant Pai supervised the writing and submission of this case report. The patient received direct clinical care from Fatma Kassem Mohamed, Maha M. El Shafei, and Anant Pai. Hashem Abu Serhan reviewed the manuscript before submission.

All data generated or analyzed during this study are included in this article. Further inquiries can be directed to the corresponding author.