Prevention and treatment of injection-related endophthalmitis

Intravitreal Injections with Vascular Endothelial Growth Factor Inhibitors: A Practical Approach

Intravitreal injections with vascular endothelial growth factor inhibitors constitute the most prevalent ophthalmic procedure in developed countries. Historically, there has been steady growth in the number of treatments performed of this kind, and projection studies estimate further growth in such treatments in the future. We provide a practical approach to intravitreal injections and discuss important aspects relating to the setting, the patient, the procedure, and the information given to the patient.

Prophylaxis measures for postinjection endophthalmitis

Intravitreal injections have become the most commonly performed ophthalmic procedure, transforming modern retina practice. Postinjection endophthalmitis, while rare, remains the most feared potential complication. Prophylaxis measures including topical antisepsis, hand hygiene, gloves, masks, and drapes have all been proposed to help prevent postinjection endophthalmitis; however, there remains significant variation in protocol, given the lack of agreement among retina specialists on which steps are crucial to prevent endophthalmitis. With millions of injections performed annually, collating data have helped us better understand risk factors for endophthalmitis after intravitreal injection. We summarize the consensus guidelines for intravitreal injection technique and comprehensively review the literature on prevention of postinjection endophthalmitis.

Endophthalmitis in Oslo, Norway

PURPOSE

To study the incidence, aetiology, pathogenic causes, treatment and visual outcomes of endophthalmitis (EO) at the Department of Ophthalmology, Oslo University Hospital (OUS), Norway.

METHODS

Retrospective registry study. Medical records of all EO patients treated at OUS over a 2-year period were reviewed.

RESULTS

The study identified 46 EO eyes of 44 patients; 19 eyes had postcataract surgery EO (PCE), and 6 eyes had postinjection EO (PIE). Of 4778 primary cataract surgeries performed at OUS, there was one PCE (incidence 0.21 per 1000; 95% CI 0.04-1.19 per 1000). Of 38 134 intravitreal injections performed at OUS, there were 3 PIE (incidence 0.08 per 1000; 95% CI 0.03-0.23 per 1000). Among 15 751 cataract surgeries performed at other ophthalmic centres in Oslo and Akershus County (OOC), there were 15 PCE (incidence 0.95 per 1000; 95% CI 0.58-1.57 per 1000). Of 3000 intravitreal injections performed at OOC, there was one PIE (incidence 0.33 per 1000; 95% CI 0.059-1.89 per 1000). For neither PCE nor PIE, there were significant differences in odds ratios between OUS and OOC. The odds ratio for PCE versus PIE was, however, 8.0 (95% CI 2.7-24.0; p < 0.001). Cultures were positive in 35 of 46 eyes (76%). The most common pathogen was Staphylococcus epidermidis. Twenty-two eyes (48%) achieved a clinically significant improvement in visual function (≥0.3 logMAR) following treatment.

CONCLUSION

The overall risk of PCE and PIE was low. It was, however, higher for PCE than PIE, probably reflecting the relative difference in invasiveness between the procedures.

The treatment of postoperative endophthalmitis: should we still follow the endophthalmitis vitrectomy study more than two decades after its publication?

Conducted in the early 1990s Endophthalmitis Vitrectomy Study (EVS) have helped in establishing reasonable guidelines for the management of infectious postoperative endophthalmitis. However at present, more than 20 years after its publication, tremendous progress has been introduced in vitrectomy technology, which now permits the vitreoretinal surgeon to perform surgery more safely, and with better outcomes. Moerover, performing a complete vitreous removal, along with the moving up of the surgical intervention to as early as possible allows the prevention of complications that would limit the functional improvement postoperatively. Thus, it is now highly needed to re-evaluate the conclusions of the EVS study.

Current Evidence for the Prevention of Endophthalmitis in Anti-VEGF Intravitreal Injections

Intravitreal injection of a therapeutic substance is the most common procedure performed in ophthalmology. It has a low incidence of serious complications but is associated with a small chance of endophthalmitis. Although the rate of endophthalmitis is between 0.019% and 0.09%, the associated visual morbidity is often devastating. Procedural changes have evolved over the years to improve patient comfort and reduce injection-related injury and infection. Despite the availability of published evidence, there remains considerable variations and lack of consensus in practical clinical settings. In addition, emerging literature concerning the use of speculums, the use of prophylactic topical antibiotics, and the setting of injections continues to impact the ophthalmologist's injection practice. This article provides an up to date assessment of various aspects of the procedure such as the setting, ventilation, type of anaesthetic, and control of sterility during the procedure; including discussions on performing bilateral eye same-day injections and the use of antibiotics.

Complications of Intravitreous Injections in Patients with Diabetes

Intravitreous injections are presently the second most frequently performed ophthalmic procedure and the most common vitreoretinal procedure. In diabetic patients, intravitreous injections are frequently performed for the treatment of center-involved diabetic macular edema, proliferative diabetic retinopathy, or other co-existing retinal vascular disease. Diabetic patients may be at higher risk of adverse events compared to non-diabetic individuals, given frequent systemic comorbidities, such as cardiovascular and renal disease and increased susceptibility to infection. This review highlights the potential complications and safety considerations in intravitreous injections in patients with diabetes.

Acute bacterial endophthalmitis following intravitreal dexamethasone implant: A case report and review of literature

Endophthalmitis following intravitreal dexamethasone (DEX) implant has been rarely reported. This report describes the case of a 70-year-old male who underwent intravitreal DEX implant injection under aseptic conditions, for diabetic macular edema. He developed a clinical picture suggestive of endophthalmitis within 2 weeks of the injection, and vitreous culture grew coagulase negative Staphylococcus. He was treated with intravitreal antibiotics followed by pars plana vitrectomy and removal of the implant. This was followed by resolution of the infection with a favorable final visual outcome. The challenges faced during surgical management of this case are discussed.

TWO CASES OF ACUTE ENDOPHTHALMITIS AFTER INTRAVITREAL DEXAMETHASONE IMPLANT INJECTION

PURPOSE

To present two cases of acute endophthalmitis after intravitreal dexamethasone implant injection and discuss the management of intravitreal implant-associated endophthalmitis.

METHODS

Two patients, who underwent intravitreal dexamethasone implant injection for macular edema secondary to diabetic retinopathy in one and branch retinal vein occlusion in the other, were admitted with decreased vision, pain, and redness in their treated eyes, 3 days and 5 days after the injection, respectively. The clinical findings of both patients were consistent with acute endophthalmitis.

RESULTS

After obtaining aqueous and vitreous samples, the patients were treated with intravitreal antibiotic injection and topical fortified antibiotics. Both patients revealed favorable clinical response and functional vision was recovered.

CONCLUSION

Intravitreal dexamethasone implant-associated endophthalmitis is an uncommon and a challenging situation. Intravitreal antibiotics may lead to favorable visual outcomes without the need for a pars plana vitrectomy and implant removal in selected cases.

Current Perspectives of Prophylaxis and Management of Acute Infective Endophthalmitis

Endophthalmitis is an intraocular inflammatory condition which may or may not be caused by infective agents. Noninfectious (sterile) endophthalmitis may be attributable to various causes including postoperative retained soft lens matter or toxicity following introduction of other agents into the eye. Infectious endophthalmitis is further subdivided into endogenous and exogenous. In endogenous endophthalmitis there is hematogenous spread of organisms from a distant source of infection whereas in exogenous endophthalmitis direct microbial inoculation may occur usually following ocular surgery or penetrating eye injury with or without intraocular foreign bodies. Acute infective endophthalmitis is usually exogenous induced by inoculation of pathogens following ocular surgery, open-globe injury and intravitreal injections. More infrequently the infective source is internal and septicemia spreads to the eye resulting in endogenous endophthalmitis. Several risk factors have been implicated including immunosuppression, ocular surface abnormalities, poor surgical wound construction, complicated cataract surgery with vitreous loss and certain types of intraocular lens. Comprehensive guidelines and recommendations on prophylaxis and monitoring of surgical cases have been proposed to minimize the risk of acute endophthalmitis. Early diagnosis and prompt management of infective endophthalmitis employing appropriately selected intravitreal antibiotics are essential to optimize visual outcome.

Endophthalmitis following intravitreal injection of anti-VEGF agents: long-term outcomes and the identification of unusual micro-organisms

Background

While the development of targeted molecular therapy to inhibit vascular endothelial growth factor (VEGF) has revolutionized the treatment and visual prognosis of highly prevalent retinal diseases such as diabetic retinopathy and age-related macular degeneration, each intravitreal injection of these agents carries a small risk of endophthalmitis which can be visually devastating. In the absence of specific guidelines, current management of post-injection endophthalmitis is typically extrapolated from data regarding endophthalmitis occurring after cataract surgery despite potential differences in pathogenic organisms and clinical course. Here, we assess the contribution of intravitreal injections of anti-VEGF agents to all cases of endophthalmitis at our tertiary care referral center and characterize the clinical outcomes and microbial pathogens associated with post-injection endophthalmitis in order to inform management of this serious iatrogenic condition.

Results

During the 7-year study period analyzed, 199 cases of endophthalmitis were identified using billing records. Of these, the most common etiology was post-surgical, accounting for 62 cases (31.2 %), with bleb-associated, endogenous, and corneal ulcer-related infections representing the next most frequent causes, comprising 15.6 % (31/199), 13.1 % (26/199), and 13.6 % (27/199) of all cases, respectively. Intravitreal injections of anti-VEGF agents represented 8.5 % of endophthalmitis (17/199 cases). Intraocular cultures yielded positive results in 75 % of post-injection cases, with the majority associated with coagulase-negative Staphylococcus. Consistent with prior literature, a case of Strep viridans displayed more rapid onset and progression. We also report the first association of Enterobacter cloacae and Lactococcus garvieae with post-injection endophthalmitis. While all but one patient were treated with initial vitreous tap and intravitreal injection of antibiotics, both patients with these rare organisms exhibited persistent vitritis requiring subsequent vitrectomy. Long-term outcomes of post-injection endophthalmitis indicated visual recovery to baseline levels, even with resumption of anti-VEGF agents following resolution of the acute infection.

Conclusions

Acute endophthalmitis following intravitreal injections of anti-VEGF agents is an uncommon but potentially devastating complication which may be managed effectively with vitreous tap and injection of intravitreal antibiotics. However, persistent vitritis requiring subsequent vitrectomy should raise suspicion for unusual pathogens.

A Prospective Study on the Clinical and Microbiological Spectrum of Endophthalmitis in a Specific Region in Denmark

PURPOSE

To study the clinical and microbiological spectrum of endophthalmitis with emphasis on clinical features, visual outcomes and risks of surgical complications.

METHODS

A prospective observational study was conducted between 2012 and 2013 in a specific region in Denmark. Patients were clinically examined before, during and after surgical intervention for endophthalmitis.

RESULTS

Fifty eyes with endophthalmitis were included. Endophthalmitis after cataract surgery (post-cataract), anti-VEGF (vascular endothelial growth factor) intravitreal injections (post-injection) and cases of endogenous endophthalmitis were responsible for 40, 28 and 18% of all cases, respectively. There was no difference in the microbiological spectrum in post-cataract patients and post-injection patients, but patients with post-cataract endophthalmitis presented statistically significantly more frequently with hypopyon and fibrin in the anterior chamber. Between 20 and 25% of post-cataract and post-injection endophthalmitis patients developed a surgical complication after primary surgical intervention for endophthalmitis, and this was statistically significantly associated with a poor visual outcome. There was no statistically significant difference in the risk of surgical complications in phakic and pseudophakic eyes with post-injection endophthalmitis. Of the 8 patients with endogenous endophthalmitis, 67% developed a surgical complication, and these patients had a high mortality. The visual outcome in the most common types of endophthalmitis was good, with 60% of post-cataract patients achieving a visual outcome ≥ 0.5, and 64% of post-injection patients only had a mild vision loss (1-14 ETDRS letters) or even gained vision.

CONCLUSIONS

The endophthalmitis cases had a broad clinical spectrum. Surprisingly, endogenous endophthalmitis accounted for almost one fifth of all cases. Patients with post-cataract endophthalmitis had a clinically different presentation than patients with post-injection endophthalmitis. In general, the bacteria were low-virulent and the visual outcomes good, but a substantial part of the patients developed a surgical complication which was associated with a poor visual outcome.