Unusual clinical features and histopathological findings in a case of Pseudo-endophthalmitis in neovascular glaucoma

Objective: This case report aimed to describe the unusual clinical presentation and histopathological features of post-injection endophthalmitis. Methods: A 56-year-old male phakic patient with diabetic retinopathy received an intravitreal injection (Bevacizumab as per the patient) for neovascular glaucoma elsewhere and presented to our center one day after the dose with hypopyon. The eye was relatively white without pain or lid oedema. The patient was treated as a case of post-injection endophthalmitis with two doses of intravitreal antibiotics 48 hours apart. During the follow-up, he developed a Covid infection. After one week, when the media cleared, white exudates were seen in the vitreous cavity with a relatively healthy retina. He was taken up for pars plana vitrectomy and vitreous biopsy for histopathological study. Results: The microscopic examination of vitreous aspirate revealed crystalline deposits without any microorganisms. Two control slides, one with a mixture of intravitreal antibiotics, which were previously injected, and the other with fresh Triamcinolone were also examined. Although the findings of the drug mixture did not match the vitreous aspirate, they matched with triamcinolone, which established it as a case of pseudo endophthalmitis due to triamcinolone injected elsewhere. Discussion: Initially, it seemed like a straightforward case of post-injection endophthalmitis, but a further examination of the vitreous aspirate showed that it was pseudoendophthalmitis due to an intravitreal triamcinolone injection. Despite the patient being phakic, neovascularization or elevated intraocular pressure may have led to the disruption of the blood-ocular barrier and the migration of Triamcinolone into the anterior chamber. Conclusion: The case's uniqueness lies in being the first reported case of pseudo endophthalmitis in a phakic patient with an intact lens iris diaphragm. The case also highlighted the judicious use of available resources and out-of-the-box thinking to reach a diagnosis that may not always be obvious. Abbreviations: TA = Triamcinolone acetonide, AC = Anterior chamber, IVB = Intravitreal Bevacizumab, PL = Perception of light.