David W. Parke

Bacterial Endophthalmitis: Epidemiology, Therapeutics, and Bacterium-Host Interactions

SUMMARY Endophthalmitis is a severe inflammation of the interior of the eye caused by the introduction of contaminating microorganisms following trauma, surgery, or hematogenous spread from a distant infection site. Despite appropriate therapeutic intervention, bacterial endophthalmitis frequently results in visual loss, if not loss of the eye itself. Although the pathogenicity of bacterial endophthalmitis has historically been linked with toxin production during infection, a paucity of information exists as to the exact mechanisms of retinal toxicity and the triggers for induction of the intraocular immune response. Recently, research has begun to examine the bacterial and host molecular and cellular events that contribute to ocular damage during endophthalmitis. This review focuses on the causative agents and therapeutic challenges of bacterial endophthalmitis and provides current data from the analysis of the role of bacterial virulence factors and host inflammatory interactions in the pathogenesis of eye infections. Based on these and related studies, a hypothetical model for the molecular pathogenesis of bacterial endopthalmitis is proposed. Identifying and understanding the basic mechanisms of these bacterium-host interactions will provide the foundation for which novel, information-based therapeutic agents are developed in order to prevent vision loss during endophthalmitis.

Endogenous Endophthalmitis Among Patients with Candidemia

Thirty-eight patients with fungemia were examined prospectively for development of endophthalmitis. Endophthalmitis was present in 10 of 27 (37%) patients with Candida albicans fungemia. Only one patients with nonalbicans fungemia developed endophthalmitis. Of the preselected factors studied, only hemodialysis and parenteral hyperalimentation correlated with an increased incidence of endophthalmitis. Antibody titers by latex agglutination were of little predictive value for endophthalmitis. Antigen titers by latex agglutination were performed in four cases with endophthalmitis. Antigenemia was demonstrated in three of the four patients, all of whom had negative antibody serologies. Although inconclusive, the preliminary data indicate the test may prove to be of clinical value. Periodic ophthalmoscopic examinations should be considered mandatory in the evaluation of patients with fungemia.

Intraocular Argon Laser Photocoagulation in the Management of Severe Proliferative Vitreoretinopathy

We surgically repaired seven eyes with severe proliferative vitreoretinopathy with intraocular argon laser photocoagulation. Five of the seven retinas were still attached six or more months postoperatively. Endolaser photocoagulation was used in conjunction with pars plana vitrectomy, periretinal membrane stripping, fluid-air exchange, and planned retinotomies. The advantages of endolaser photocoagulation include easier management of posterior retinotomies in an air-filled eye, isolation of anterior traction and retinal breaks by creating an encircling demarcation line posterior to the problem, and less manipulation of existing scleral buckling material.

Granulocytic Sarcoma of the Orbit: A Clinicopathologic Study

A 9-year-old Latin American girl developed proptosis of the left eye associated with pain in the left ear of one months duration. Ophthalmoscopic examination of the left eye disclosed retinal striae with venous tortuosity and papilledema. CT scan of the orbit showed a nonenhancing, irregular intraconal mass. CT scan of the brain demonstrated an enhancing left temporoparietal mass. Craniotomy revealed a 7 cm, extra-axial mass that was attached to the dura mater. Histologic examination, including a positive Leder stain, established the diagnosis of granulocytic sarcoma. At that time, the results of the laboratory studies, including complete cell blood count, were normal. Periodic clinical and hematologic evaluation was recommended. Twenty-five days after craniotomy, examination of the peripheral blood disclosed 56% myeloblasts and the bone marrow contained 30% blast cells. The problem in histologic differential diagnosis and a review of the literature is discussed.

Host/Parasite Interactions in Bacterial Endophthalmitis

Bacterial infections within the eye arise as complications of intraocular surgery, penetrating injury, or hematogenous spread from distant anatomical sites. Because: 1) the interior surfaces of the eye are lined with sensitive, nonregenerating tissues, 2) the inner chambers of the eye are relatively sequestered from circulating immunological components, 3) the integrity of blood-ocular barriers provides poor penetration of systemically administered antibiotics, and 4) aqueous and vitreous humor represent rich, relatively acellular culture media; endophthalmitis often progresses rapidly and total loss of vision frequently results. Years of clinical experience have shown that current therapies for endophthalmitis, including antimicrobials, antiinflammatory agents, and vitrectomy, are frequently unsuccessful in ameliorating destruction of intraocular tissues. While bacterial and host factors were thought to play key roles in the course and severity of endophthalmitis, it is only recently that their contributions have been experimentally defined. Molecular-based techniques are gaining increased use in the study of infectious eye diseases. Current findings regarding the host/parasite interactions within the eye are reviewed, and a resulting integrative model of the natural course of endophthalmitis proposed. A molecular-level understanding of the roles of both bacterial and host factors during endophthalmitis will likely reveal potential targets for therapeutic intervention aimed at salvaging vision.

The American Academy of Ophthalmology's IRIS® Registry (Intelligent Research in Sight Clinical Data): A Look Back and a Look to the Future

The seeds for the Academy’s IRIS Registry (Intelligent Research in Sight) were planted more than 3 decades ago with the initiation of the Academy’s Quality of Care Committee in 1985. This blossomed into one of the first medical society practice guidelines for improving care and promoting best practices based on expert consensus and scientific evidence from the peer-reviewed literature, known as the Preferred Practice Patterns. The committee then turned its focus on patient outcomes, with the launch of a National Eyecare Outcomes Network for measuring cataract surgery performance in 1995. At its peak, National Eyecare Outcomes Network collected data on 17 000 patients’ preoperative characteristics, operative parameters, and postoperative outcomes, but subsequently met its demise because the time

The Preferred Practice Pattern Guidelines in Ophthalmology

The Academy’s Preferred Practice Pattern (PPP) guidelines have had a lengthy evolution since 1985, when the Academy was one of the first medical specialty societies to embark on guideline development. The Institute of Medicine’s landmark reports on clinical practice guidelines, defined as “systematically developed statements to assist practitioner and patient decisions about appropriate health care for specific clinical circumstances,” ushered in an era of guideline proliferation. In 2011, the Institute of Medicine reported that there were more than 3700 guidelines from 39 countries in the Guidelines International Network library. Currently, there are 6187 guidelines originating from 76 countries. The United States National Guideline Clearinghouse contains 2361 individual guideline summaries. Guidelines serve as the foundation for quality and performance measures, quality

The American Academy of Ophthalmology and the Formation of the American Board of Ophthalmology

At the turn of the 20th century, the American Academy of Ophthalmology and Otolaryngology joined the American Ophthalmological Society and the Section on Ophthalmology of the American Medical Association to form Americas first board for the certification of medical specialists, the American Board of Ophthalmology. Academy leaders helped pave the way for the development of rigorous standards for the training of ophthalmologists and pushed for the advancement of excellence within the profession.