Severe infectious keratitis in tropical environments: 118 cases collected over 10 years

The aim of our study was to evaluate the clinical, microbiological, and contributing factors of microbial keratitis in tropical environment. Materiel and methods: We performed a retrospective study of all patients admitted to the ophthalmology department of Principal Hospital in Dakar for infectious keratitis, over ten years from January 2006 to December 2015. Clinical, microbiological, and contributing factors as well as visual effects were studied.

We collected data of 118 patients hospitalized for unilateral infectious keratitis in 10 years, for an average of 12 cases per year. The patients' mean age was 50 years. At least one local risk factor was found in 58.5% of cases. These were mainly ocular trauma (39%), followed by local treatment of glaucoma (16%), and recent eye surgery (14.5%). In 9 cases (8%), the only risk factor for abscess was an isolated general factor. This was diabetes in 7 cases. The clinical aspects described can be grouped according to topography, depth, and severity in pre-perforation state or perforation (45%), anterior chamber Tyndall effect greater than 1 cross, reaching a hypopyon stage (24%), stromal infiltrate larger than 2 mm (18%) and the abscess located within 3 mm of the corneal center (13%). The microbiological examination isolated a germ in 17% of cases, principally Pseudomonas aeruginosa (40%), followed by Staphylococcus aureus (20%). Prognosis was severe with visual acuity of less than 1/10 in 90% of cases and evisceration in 16% of cases.

The most common risk factor was local ocular trauma by foreign bodies in the cornea. The poor prognostic factors were possible delay in consultation, low initial visual acuity, and low rate of positive microbiological examinations.

Infectious keratitis is a potentially serious condition that can lead to blindness and eventually to loss of the ocular globe in tropical environments. Local risk factors are largely dominated by ocular trauma. Only early management based on the microbiological results improves the prognosis.