Despite being a preventable and treatable condition, central microbial keratitis (CMK) and its complications remain to be a significant cause of vision loss in our country. This study presents the demographic profile, risk factors, etiologies, treatments, and outcomes of CMK in the Philippines.

The study was a two-center, prospective, non-randomized clinical study involving the patients of the External Disease and Cornea Clinics of two tertiary eye referral centers in the Philippines. It was conducted as the Philippine leg of the Asia Cornea Society Infectious Keratitis Study (ASCIKS).1 Patients with a clinical diagnosis of CMK rendered by a cornea specialist, and who signed the consent form, were recruited into the study. They underwent uniform sample collection and culture techniques as described in the ACSIKS. All patients were followed-up for 6 months. Data collected included demographics, risk factors, culture results, management, and treatment outcomes. Descriptive statistics and frequency were used to analyze the data.

A total of 348 patients diagnosed with CMK were included. Trauma (65.5%) among the middle-aged (42.9 ± 17.9 years) male population was the most significant risk factor for development of CMK, followed by contact lens wear (12.9%), prior ocular surgery (6.0%), and ocular surface diseases (3.4%). Bacterial keratitis (53.2%) was still the most common etiology of CMK, followed by fungal keratitis (27.0%), Acanthamoeba keratitis (5.7%), and viral keratitis (2.0%). Aspergillus species (18.3%) were the most common microbial isolates. Pseudomonas species (13.9%) were the most common bacterial isolates. The median time from onset of symptoms to consultation with the study centers was 2 weeks. Medical treatment was enough to treat the infection in 34.8% of cases. Surgical intervention was necessitated in 22.6% with evisceration/enucleation done in 1 out of 3 patients who had surgery.

Bacterial infection remains the most common cause of CMK in the Philippines, followed by fungal infection. Significant risk factors include trauma and contact lens wear. Aspergillus species and Pseudomonas species were the most common fungal and bacterial isolates, respectively. Despite medical treatment, almost a quarter of the cases still required surgical intervention.