Table 1.

Summary of findings in main infectious optic neuropathies

	Optic nerve involvement	Potential associated ocular findings	Treatment
Viral optic neuropathies
Herpes viruses
HSV (types 1 and 2)	Papillitis, neuroretinitis, retrobulbar optic neuropathy, and optic disc atrophy	Necrotizing retinitis, vitritis, arteritis	Acyclovir Systemic corticosteroids (controversial)
VZV	Varicella: papillitis	Anterior uveitis	Antiviral therapy (controversial) Systemic corticosteroids (controversial)
	HZO: papillitis, retrobulbar optic neuritis	Skin rash, keratitis, anterior uveitis, necrotizing retinitis	Systemic acyclovir and corticosteroids
	Progressive outer retinal necrosis: optic disc edema, optic disc atrophy, retrobulbar optic neuropathy	Necrotizing retinitis	Antiviral therapy
CMV (herpesvirus 5)	Papillitis, retrobulbar optic neuritis	Retinitis	Antiviral therapy with or without associated corticosteroid therapy
EBV (herpesvirus 6)	Papillitis, retrobulbar optic neuritis, neuroretinitis, chiasmal involvement	Retinitis, chorioretinitis	Oral or intravenous corticosteroid therapy
HIV	Retrobulbar optic neuropathy, papillitis, ischemic optic neuropathy, optic disc pallor	Cotton-wool spots, microaneurysms, retinal hemorrhages, uveitis	Antiretroviral drugs, corticosteroids, and tumor necrosis factor antagonists
Arboviruses
West Nile virus	Optic neuritis, neuroretinitis, optic disc swelling, optic disc staining on fluorescein angiography, papilledema, optic atrophy	Multifocal chorioretinitis	No effective treatment
Chikungunya	Unilateral or bilateral papillitis, retrobulbar neuritis, neuroretinitis	Retinitis, retinochoroiditis, mild vitritis, retinal vasculitis	Corticosteroid therapy
Dengue virus	Neuroretinitis, optic disc swelling, optic neuritis, neuromyelitis optica	Dengue maculopathy	No specific treatment
Rift valley fever virus	Optic disc edema, optic atrophy	Anterior uveitis, macular or paramacular necrotizing retinitis, retinal hemorrhages, vitritis, retinal vasculitis	Corticosteroid therapy (controversial)
Other viruses
Influenza virus	Neuroretinitis, neuromyelitis optica	Retinitis, choroiditis, retinal hemorrhages	Corticosteroid therapy (controversial)
Mumps	Papillitis, retrobulbar optic neuritis, neuroretinitis, optic atrophy	Anterior uveitis	Corticosteroid therapy (controversial)
Rubella	Optic neuritis	Anterior uveitis	Corticosteroid therapy (controversial)
Measles	Optic neuritis and retrobulbar optic neuropathy with or without associated encephalomyelitis	Conjunctivitis, keratitis	Corticosteroid therapy
Bacterial optic neuropathies
Cat scratch disease	Neuroretinitis	Retinitis, retinal vasculitis	Doxycycline 100 mg twice daily for 4–6 weeks in immunocompetent patients and 4 months in immunocompromised patients Corticosteroid therapy (controversial)
Ocular tuberculosis	Papillitis, neuroretinitis, optic nerve tubercle, compressive optic neuropathy, anterior ischemic optic neuropathy, optic atrophy, optic chiasmatic arachnoiditis	Choroiditis, retinal vasculitis, tubercular choroidal lesions	Anti-tubercular treatment for 9–12 months Corticosteroid therapy (controversial) Neurosurgical decompression of the anterior visual pathways for optic chiasmatic arachnoiditis
Syphilis	Papillitis, perineuritis, chiasmal syndrome, gumma of the optic disc, neuroretinitis, optic disc cupping	Retinitis, retinal vasculitis	Intravenous penicillin G or intramuscular procaine penicillin for 10–14 days along with oral probenecid with or without systemic or periocular corticosteroids
Lyme disease	Papilledema, papillitis, neuroretinitis, ischemic optic neuropathy, chiasmal syndrome	Retinitis, retinal vasculitis	Intravenous ceftriaxone (2 g IV once daily) for at least 3 weeks
Rickettsioses	Optic disc swelling, optic disc staining on fluorescein angiography, optic neuritis, neuroretinitis, ischemic optic neuropathy, papilledema, optic atrophy	Retinitis, retinal vasculitis	Doxycycline 200 mg/day for 2 weeks Corticosteroid therapy (controversial)
Q fever	Optic neuritis	Retinitis, retinal vasculitis	Antibiotics and corticosteroid therapy are controversial
Whipple’s disease	Optic neuritis, optic disc edema, optic atrophy	Vitritis, retinal vasculitis	Systemic trimethoprim–sulfamethoxazole associated with rifampin, for at least 1 year
Brucellosis	Optic neuritis, papilledema	Vitritis, choroiditis	Antibiotics and corticosteroid therapy
Leptospirosis	Optic disc hyperemia, optic neuritis, papillitis, neuroretinitis	Vitritis, retinal vasculitis, retinal hemorrhages	Antibiotics and corticosteroid therapy
Leprosy	Papillitis, optic atrophy	Dacryoadenitis, disorder of the eyelid, uveitis	Systemic dapsone and rifampin Systemic corticosteroids
Parasitic optic neuropathies
Toxoplasmosis	Optic disc hyperemia, neuroretinitis, papillitis, isolated anterior optic neuritis	Retinochoroiditis, retinal vasculitis, vitritis	Pyrimethamine (100 mg on day 1 followed by 50 mg daily; 25 mg in children) and sulfadiazine 4 g/day with folinic acid Other alternatives: oral or intravitreal, clindamycin, spiramycin, azithromycin, trimethoprim–sulfamethoxazole Systemic corticosteroids
Toxocariasis	Papillitis, retrobulbar optic neuritis, neuroretinitis, optic disc granuloma	Vitritis	Periocular and systemic corticosteroids
Diffuse unilateral subacute neuroretinitis	Optic disc edema, optic disc atrophy	Chorioretinitis, retinal vessel narrowing, focal or diffuse retinal pigment epithelium degeneration	Laser therapy, when the nematode is visible, and chemotherapy with anthelmintic drugs, such as mebendazole, thiabendazole, or albendazole when a worm cannot be visualized Corticosteroid therapy
Fungal optic neuropathies
Cryptococcus	Optic neuritis after cryptococcal meningitis, retrobulbar optic neuropathy	Chorioretinitis	Intravitreal and/or intravenous amphotericin B
Candida	Optic disc edema associated with chorioretinitis	Chorioretinitis, vasculitis, retinal hemorrhages, vitreous exudates	Systemic and/or intravitreal antifungal agents (amphotericin B, fluconazole, and voriconazole)
Presumed ocular histoplasmosis syndrome	Ring of peripapillary atrophy with a narrow inner pigment zone adjacent to the disc edge and a white depigmented zone away from the optic disc	Atrophic choroidal scars, choroidal neovascularization	No specific treatment
Aspergillus	Optic neuritis, orbital apex syndrome		Intensive antifungal therapy with amphotericin B, surgical excision of involved tissue with sinus exenteration
Mucormycosis	Optic nerve infarction and necrosis	Proptosis, conjunctival injection, restricted extraocular motility	Amphotericin B, surgical debridement
Post-vaccination optic neuropathies	Anterior or retrobulbar optic neuritis, neuroretinitis		Corticosteroid therapy

Abbreviations: CMV, cytomegalovirus; EBV, Epstein-Barr virus; HSV, herpes simplex virus; HIV, human immunodeficiency virus; HZO, herpes zoster ophthalmicus; VZV, varicella zoster virus.