Microbiological profile of orbital abscess

Abstract

Background: Knowledge of the culture and sensitivity pattern is necessary, for the institution of appropriate empirical antibiotic therapy in orbital abscess.

Objective: The objective of this study is to describe culture and sensitivity patterns of specimens from the orbit and surrounding structures.

Materials and methods: Retrospectively the medical records of 56 cases of orbital abscess were reviewed.

Results: Cultures were positive in 38/56 (68.8%) orbital specimens and the organisms included Staphylococcus aureus 18, Streptococci 7, Pseudomonas aeruginosa 3, 2 each of Enterobactersp, Escherichia coli, Proteus mirabilis, Acinetobacter sp. and 1 each of Actinomyces israelii, Diptheroids, Coagulase negative Staphylococcus, Citrobacter freundii, Methicillin-resistant S. aureus and Enterococcus faecalis. Four had polymicrobial infection. Culture of purulent nasal discharge, swabs taken from foci of infection on the face, and blood cultures were done in 26/56, and positive cultures were obtained in 16/26 (61.5%) specimens. In 12 patients, there was a concurrence in the organism cultured from the orbit and from cultures from other sites. Gram-negative organisms were associated with increased ocular morbidity.

Conclusion: Gram-positive cocci, especially S. aureus are the most common organisms isolated from orbital abscesses. Infections by Gram-negative organisms were associated with more complications. Empirical intravenous antibiotic therapy should have a broad spectrum of activity effective against a wide range of Staphylococcal organisms and Gram-negative bacilli.