Copyright © 2017 Wolters Kluwer Health, Inc. All rights reserved. C URRENT O PINION Ophthalmic manifestations of bartonella infection Radgonde Amer a and Ilknur Tugal-Tutkun b Purpose of review The eye is commonly affected in disseminated cat scratch disease (CSD) caused by Bartonella species. This article reviews recently published data on epidemiology of CSD, clinical features of ocular involvement, diagnosis and treatment. Recent findings The annual incidence of CSD has been estimated as 4.7 per 100 000 in the United States. It occurs predominantly in the southern states, with a peak in January, and disproportionately affects children. Retinal infiltrates, neuroretinitis and branch retinal artery occlusions have been reported as common manifestations of ocular bartonellosis in recent series. The use of different antigens for serodiagnosis and new real-time PCR assays for molecular diagnosis have been described. Despite lack of a standard treatment, good visual outcomes were generally reported in patients with ocular bartonellosis. Summary Bartonella infections continue to be a burden worldwide and epidemiologic features may guide preventive measures in high-risk regions and populations. An increased awareness of diverse posterior segment manifestations will lead to an early diagnosis of ocular bartonellosis. Laboratory diagnostic methods continue to evolve and may be applied to the investigation of ocular fluids for a definitive diagnosis of ocular bartonellosis. Well designed clinical trials are required to establish the optimum treatment of especially sight-threatening manifestations. Keywords bartonella, cat-scratch disease, neuroretinitis, ocular bartonellosis INTRODUCTION Bartonella spp. are small, gram-negative, haemo- tropic intracellular bacilli that are typically transmitted by blood-sucking insects such as phlebotomine sandflies, human body lice, cat fleas, ticks or via animal scratches and bites [1]. The majority of human infections are caused by Bartonella henselae, Bartonella quintana and Bartonella bacilliformis, although other Bartonella spp. have also been associated with human diseases. The severity of Bartonella infection correlates with the patient’s immune status. Immunocompe- tent individuals typically develop cat scratch disease (CSD), which is a self-limiting swelling of the lymph nodes that drain the primary inoculation site. A disseminated infection may occur in 5–14% of cases, and ocular involvement, also called ocular bartonellosis, is a relatively common manifestation of disseminated CSD [1]. The purpose of this article is to review recently published literature related to ocular bartonellosis. EPIDEMIOLOGY Recently, Nelson et al. [2 && ] conducted a retrospec- tive analysis of the Truven Health MarketScan Commercial Claims and Encounters database for 2005 – 2013. The database contained records for per- sons less than 65 years of age only. The authors estimated that the annual incidence of CSD was 4.7 per 100 000 persons less than 65 years of age and that a total of 12 500 patients in this age group received a CSD diagnosis each year in the United States. The highest rates of outpatient diagnoses and inpatient admissions for CSD occurred among a Department of Ophthalmology, Hadassah Medical Center, Jerusalem and b Department of Ophthalmology, Istanbul University, Istanbul Faculty of Medicine, Istanbul, Turkey Correspondence to Prof. Ilknur Tugal-Tutkun, Istanbul Tip Fakultesi, Go ¨z hastaliklari Anabilim Dali, C ¸ apa, Istanbul 34093, Turkey. Tel: +90 532 4141606; fax: +90 216 6401578; e-mail: itutkun@yahoo.com; itutkun@istanbul.edu.tr Curr Opin Ophthalmol 2017, 28:607–612 DOI:10.1097/ICU.0000000000000419 1040-8738 Copyright ß 2017 Wolters Kluwer Health, Inc. All rights reserved. www.co-ophthalmology.com REVIEW