Pneumococcal Endophthalmitis: A Rare Threat Observed Years After Glaucoma Surgery

To the Editors: We read with great interest the article by Kasem Ali Sliman et al1 regarding pediatric infectious endophthalmitis over the 5 last decades. A total of 796 patients and 799 eyes were included in the study. Ocular trauma was the leading cause, affecting 623 patients (78.3%), followed by postsurgery in 100 (12.6%) and endogen endophthalmitis in 67 (8.4%) (70 eyes). While the most common cause of endophthalmitis developing after surgery was cataract (30%), the development of endophthalmitis after glaucoma surgery (15%) was the second most common cause. More than half of the endophthalmitis that developed after surgery was gram positive, while pneumococci accounted for 32.6% of them. We would like to share our case of postsurgery endophthalmitis caused by Streptococcus pneumoniae type 15B/C. A 12-year-old male patient, who had been under follow-up in the ophthalmology department for left secondary glaucoma developed following ocular trauma, presented with decreased vision of 0.15 on the Snellen Chart. Vitreoretinal surgery was conducted following the perforation of the left eye due to ocular trauma with glass 2 years ago, and due to secondary glaucoma, Ahmed glaucoma valve implantation was performed 1 month ago. During emergency surgery, erosion of the conjunctiva over the implanted Ahmed Glaucoma Valve in the left temporal scleral region was observed, and it was covered by pericardium and amniotic membrane. In the examination performed the day after surgery, his visual acuity decreased to the level of hand movement, and endophthalmitis was diagnosed upon his detailed ophthalmological examination. After a vitreous culture was taken, the second surgery was completed with the application of intravitreal vancomycin, ceftazidime and steroid. Empirical systemic vancomycin and ceftazidime were initiated based on the most common pathogens in the patient. The vitreous culture revealed growth of Streptococcus pneumoniae. Treatment was adjusted according to the culture antibiogram to ceftriaxone and was completed over a total of 14 days. The capsular typing of Streptococcus pneumoniae resulted in 15B/C. As clinical progression continued 3 days after the second surgery, fibrinoid membranes from the anterior chamber were cleaned with a third surgery, and vancomycin, ceftazidime and steroid injections to the anterior chamber were performed. At the most recent evaluation, 2 months after the last surgery, although clinical findings regressed, postoperative visual acuity was at the level of no light perception. Our patient received 4 doses of the 13-valent conjugate pneumococcal vaccine. Pediatric infectious endophthalmitis is a rare complication that can arise from trauma, intraocular surgery or systemic infection, and it is a significant cause of blindness worldwide.2,3 If the infection progresses rapidly, it can severely damage visual function, potentially leading to permanent loss of vision due to a lack of timely and effective treatment. Additionally, children often cannot adequately understand or explain their symptoms, which may delay diagnosis and treatment. Therefore, diagnosing and treating endophthalmitis in children is more challenging; if not treated properly, bacteria and toxins can spread throughout the body, leading to systemic infection.2 A study conducted in 2019 in the United Kingdom aimed to determine the incidence and risk factors for exogenous endophthalmitis in children, finding that the incidence of postoperative endophthalmitis over 7 years was 0.17%, and that previous glaucoma surgery was a long-term risk factor. Endophthalmitis following glaucoma surgery generally occurs later due to mitomycin C use, capsule puncture and surgical exposure, highlighting the importance of long-term follow-up of the patient and examination of the conjunctiva for tube exposure.3 Our patient has undergone Ahmed Glaucoma Valve implantation due to the development of post-traumatic secondary glaucoma, and we believe that erosion of the conjunctiva over the implanted Ahmed Glaucoma Valve has predisposed to the development of endophthalmitis. The most common symptom of endophthalmitis is decreased vision affecting all patients, while eye pain or redness is also common. Our patient presented with a complaint of decreased vision, and upon examination, corneal edema and fibrinoid inflammation in the anterior chamber were detected; there were no systemic findings. Systemic symptoms such as fever are not expected in exogenous endophthalmitis cases, but fever is typically observed in endogenous endophthalmitis cases. Eye examination often reveals hypopyon in most cases.4 The use of drug therapy for endophthalmitis requires not only early treatment but also a combination of medications. Rational use of antibacterial drugs plays a crucial role in the treatment of infectious endophthalmitis, necessitating the simultaneous use of local and systemic medications due to the blood-retinal barrier. In the early stages of the disease, it is recommended to select a combination of broad-spectrum antibiotics that cover both Gram-positive and Gram-negative bacteria to better control the development of endophthalmitis.2,3 The most important component of treatment is the application of antibiotics into the eye, and visual prognosis is partly related to the virulence of the pathogen.4 Studies have shown that cases of endophthalmitis caused by S. pneumoniae have a higher rate of evisceration or enucleation requirements. In a study by Chen et al,5 visual acuity was found to be between light perception and no light perception in 84% of the 38 patients with endophthalmitis due to S. pneumoniae. The worst visual outcomes are generally seen in endophthalmitis caused by S. Pneumoniae. In line with the literature, post-treatment visual acuity was at the level of no light perception in our patient. We believe that endophthalmitis following glaucoma surgery in children is a devastating infection that can lead to vision loss and requires increased awareness in clinical practice and a multidisciplinary approach.