Listeria Infections of the Eye

Abstract

The bacterium Listeria monocytogenes resides originally in the environment. Infections of the eye have been induced experimentally; for example, in rabbits and guinea pigs. Natural ocular infections occur in various animals; in most instances, they are induced exogenously; for example, by contaminated silage affecting primarily the conjunctiva, cornea, or the anterior chamber. Sporadic infections as well as outbreaks have been described. In humans, besides exogenous infections, endogenous infections also occur, inducing mainly endophthalmitis. Since an exact diagnosis of the causative agent is often delayed, specific therapy starts too late, so that the outcome is often poor. The antibiotics of primary choice would be ampicillin or a quinolone such as moxifloxacin or levofloxacin. The role of fosfomycin for therapy of ocular infections is discussed.

Genetic diversity of Listeria monocytogenes strains in ruminant abortion and rhombencephalitis cases in comparison with the natural environment

“…Clinical isolates were defined here as isolates originating from confirmed cases of animal listeriosis. The definitions of clinical forms of listeriosis were harmonized with those previously described [25, 45, 46]. Abortion cases were defined as isolation of L. monocytogenes from the placenta and/or the fetus.…”

Listeria monocytogenes at the interface between ruminants and humans: A comparative pathology and pathogenesis review

“…88 Listerial keratoconjunctivitis is only rarely described in immunocompetent human patients, most frequently following exposure to farm environment, suggesting silage or infected animals as the origin for the infection. 143 Barely anything is known about pathogenetic mechanisms of listerial invasion into ocular tissues. Interestingly, a frequent involvement of the oculomotor nucleus in ruminant neurolisteriosis cases suggests that conjunctival tissue might provide a bacterial port of entry in neurolisteriosis, 209 although experimental conjunctival instillation of Lm in various animal species could only rarely produce encephalitis.…”

Source tracking on a dairy farm reveals a high occurrence of subclinical mastitis due to hypervirulentListeria monocytogenesclonal complexes

“…A strong link between ingestion of contaminated feed, in particular low‐quality silage, and listeriosis in ruminants has been established (Low and Donachie ; Nightingale et al ), although other on‐farm sources of infection, such as water, feeding troughs and bedding, are possible (Mohammed et al ; Oevermann et al ). In rare types of listeriosis, other (exogenous) infection routes are prominent, including ascendant infection of the udder in mastitis and direct eye inoculation in ocular listeriosis (Starič et al ; Hof ). Listeriosis usually occurs sporadically, but cases of animal outbreaks have been reported (Wiedmann et al ; Wagner et al ; Bundrant et al ; Dreyer et al ).…”