Optic Neuropathy From Viruses and Spirochetes


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IntroductionThe good physician treats the disease; the great physician treats the patient who has the disease. Sir William Osler, 1849–1919.The history of mankind and medicine can in many ways be inferred from the history of infectious disease, which has plagued humanity for millenniums.1 Biblical stories recount the terrible suffering of people and the importance of human infections in shaping the world, as we know it today. In the beginning, it was believed that infectious diseases were the result of “spontaneous generation,” but it was not until the germ theory of disease was proposed by Louis Pasteur and Robert Koch in the late 19th century that microorganisms were implicated as the source of many diseases.2,3 The impact of infectious disease on the world is devastating with nearly 15 million global deaths per year attributed to microbial pathogens.3 Emerging and reemerging infectious diseases, such as the acquired immunodeficiency syndrome, multidrug-resistant tuberculosis, vancomycin-resistant Staphylococcus aureus infections, West Nile fever (WNF), Dengue fever, Lyme disease (LD), and cholera are only a few on a long list of diseases that are, or have the potential of, disrupting the delicate balance of global health (Fig. 1).3,4 The threat of bioterrorism further highlights the importance of appreciating the various infectious pathogens that can afflict mass populations of people.5 However, it should be noted that not all microorganisms are parasitic or harmful to humans; in fact many are a necessary part of human survival, living in a mutual or commensal symbiotic relationship.This article is not meant to be an all inclusive discussion on the multitude of viral and spirochete infections causing an optic neuropathy. Instead it will review 4 viral and spirochete microorganisms that are felt by the author to be of practical interest to the ophthalmologist:Human immunodeficiency virus (HIV)West Nile virus (WNV)Borrelia Burgdorferi [Lyme disease (LD)]Treponema pallidum pallidum (syphilis).It is important to appreciate that in many cases just the mere appearance or existence of an optic neuropathy is not sufficient to determine the underlying cause.6,7 Rather it is the history, concomitant ocular, systemic and neurologic manifestations, and laboratory evaluation that will prompt the clinician to implicate a particular infectious disease or offending agent as the cause of the problem. Therefore, for each specific viral and spirochete infection the systemic, neurologic, ophthalmic, and neuro-ophthalmic manifestations will be discussed with a brief mention on diagnostic testing and treatment. The interested reader is referred to the comprehensive neuro-ophthalmic textbook, Walsh and Hoyt's Clinical Neuro-Ophthalmology, for a more complete discussion and reference list on the subject of infectious diseases, including viral and spirochete diseases of neuro-ophthalmic interest.8VirusesSome of the world's deadliest infections are the result of viral disease. Viruses are submicroscopic, obligate intracellular parasites.9 Historically, the first reference of a viral infection can be traced back to 3700 BC from a hieroglyph depicting the external manifestations of paralytic poliomyelitis. The origin of viruses remains a mystery with one popular theory, suggesting that they were at one time self-sustaining microorganisms that over time lost their genetic material to survive independently. Over 1500 viruses have been classified by the International Committee on Taxonomy of Viruses and the list is continually being updated as current and newly discovered virions are better studied and understood with modern technologies such as genome sequencing.10 It is not possible in this article to cover all the viruses of neuro-ophthalmic interest (

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