Equis ISSN 2398-2977

Uveitis: bacterial

Contributor(s): Dennis E Brooks, Graham Munroe, William C Rebhun, Craig Reinemeyer

Introduction

  • Cause: direct intraocular infection following globe penetration or surgery; hematogenous intraocular localization of systemic infections especially neonatal septicemias   Foal: neonatal septicemia syndrome  , strangles   Strangles (Streptococcus equi infection)  andRhodococcus equi  Rhodococcus equi infection  .
  • Signs: sudden onset of ocular pain, etc unilaterally if traumatic origin or often bilaterally if due to systemic infection.
  • Diagnosis: history, signs, hematology, biochemistry.
  • Treatment: rapid and intense topical and systemic therapy to minimise the long-term sequelae; aggressive treatment of any systemic diseases is essential.
  • Prognosis: varies with primary cause.

Pathogenesis

Etiology

  • Direct intra-ocular infection via trauma.
  • Post intra-ocular surgical infection.
  • Neonatal septicemias.
  • Other bacterial systemic infections.

Pathophysiology

  • Direct intraocular infection and subsequent uveitis can follow penetrating injury of the globe   Uveitis: traumatic  or intraocular surgery.
  • Hematogenous intraocular localization of systemic infection can occur in a variety of diseases.
  • Neonatal foal septicemias including:
    • Salmonellaspp   Salmonella spp  .
    • Actinobacillus equuli.
    • Streptococcusspp   Streptococcus spp  .
    • Escherichia coli  Escherichia coli  .
    • Rhodococcus equi  Rhodococcus equi  in older foals.
    • Streptococcus equi(Strangles) can produce anterior and/or posterior uveitis particularly in foals or compromised individuals.
  • Leptospirosis and brucellosis have been particularly implicated in recurrent anterior uveitis   Uveitis: recurrent  .
  • Lyme disease.
  • Rarely in adults with bacteremias, eg endocarditis   Heart: endocarditis  .
  • Adenovirus   Equine adenovirus  .
  • Equine viral arteritis (EVA)   Equine viral arteritis virus  .
  • Bacteria may become established in the eye by direct inoculation or hematogenous localization, usually in capillaries of the iris, ciliary body or choriocapillaris.
  • Damage to the ocular tissues may occur directly by the bacteria, via toxins released from the organism itself, or due to the subsequent inflammatory reaction.
  • Some organisms release damaging toxins from a site elsewhere in the body.
  • The formation of toxin antigen/antibody complexes either acutely or subsequently upon reactivation of dormant infections (uveal or remote), in sensitized individuals, can   →   further exaggerated uveal inflammatory responses   Uveitis: anterior - immune-mediated    Uveitis: recurrent  .

Diagnosis

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Treatment

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Prevention

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Outcomes

This article is available in full to registered subscribers

Sign up now to purchase a 30 day trial, or Login

Further Reading

Publications

Refereed papers

  • Recent references from PubMed and VetMedResource.
  • Nasisse M P and Nelms S (1992)Equine ulcerative keratitis.Vet Clin N A Equine Pract8(3), 537-555 PubMed.

Other sources of information

  • Brooks D E (1999)Equine Ophthalmology.In:Veterinary Ophthalmology.Ed: Gelatt K N. 3rd edn. 1053-1116.


ADDED