Epidemiology of Microbial Keratitis in Uganda: A Cohort Study

Abstract

Purpose: To describe the epidemiology of Microbial Keratitis (MK) in Uganda. Methods: We prospectively recruited patients presenting with MK at two main eye units in Southern Uganda between December 2016 and March 2018. We collected information on clinical history and presentation, microbiology and 3-month outcomes. Poor vision was defined as vision < 6/60). Results: 313 individuals were enrolled. Median age was 47 years (range 18-96) and 174 (56%) were male. Median presentation time was 17 days from onset (IQR 8-32). Trauma was reported by 29% and use of Traditional Eye Medicine by 60%. Majority presented with severe infections (median infiltrate size 5.2 mm); 47% were blind in the affected eye (vision < 3/60). Microbiology was available from 270 cases: 62% were fungal, 7% mixed (bacterial and fungal), 7% bacterial and 24% no organism detected. At 3 months, 30% of the participants were blind in the affected eye, while 9% had lost their eye from the infection. Delayed presentation (overall p = .007) and prior use of Traditional Eye Medicine (aOR 1.58 [95% CI 1.04-2.42], p = .033) were responsible for poor presentation. Predictors of poor vision at 3 months were: baseline vision (aOR 2.98 [95%CI 2.12-4.19], p < .0001), infiltrate size (aOR 1.19 [95%CI 1.03-1.36], p < .020) and perforation at presentation (aOR 9.93 [95% CI 3.70-26.6], p < .0001). Conclusion: The most important outcome predictor was the state of the eye at presentation, facilitated by prior use of Traditional Eye Medicine and delayed presentation. In order to improve outcomes, we need effective early interventions.

Mycotic Keratitis—A Global Threat from the Filamentous Fungi

“…Another study from Tanzania a few years later found the prevalence of HIV infection amongst MK cases to be double that of the wider population [ 1 ], although this did not directly compare the proportion of HIV positive fungal MK cases to bacterial MK cases. A more recent, nested case control study from Uganda where over 60% of MK cases were fungal, found a strong association between HIV infection and MK (OR 83.5, p = 0.02) [ 138 , 142 ]. There have been no studies to date looking at this association outside of SSA.…”

“…Most TEM contain non-sterile preparations comprising plant matter, often herbs or dried leaves, and are therefore a potential route for inoculating the cornea with microorganisms, particularly fungal pathogens [ 60 ]. Although there are no studies that have specifically looked at TEM as a risk factor for fungal keratitis, it has been found to be an independent risk factor in developing microbial keratitis in Tanzania and Uganda [ 20 , 138 , 142 ], where a fungal aetiology make up the majority of MK cases.…”

“…There is a history of preceding trauma in 40–60% of cases [ 60 , 70 ]. Other risk factors include previous ocular surgery [ 151 , 152 ], ocular surface disease, previous use of corticosteroids [ 146 ], contact lens use [ 213 ], immunosuppression [ 146 ], or use of traditional eye medicines [ 142 ]. Fungal keratitis caused by Fusarium spp.…”

“…In response, current and future work is focused on addressing these areas. Research projects are underway to improve the understanding of patients’ health-seeking behaviour, such as that recently completed in Uganda [ 18 , 138 , 142 ]. Linked to this is implementation research into primary preventative measures, specifically how to prevent ocular injuries from occurring in the first place.…”

Chlorhexidine gluconate 0.2% as a treatment for recalcitrant fungal keratitis in Uganda: a pilot study

“…This study is a subgroup of a previously reported cohort of 313 people with MK presenting to Mbarara University and Referral Hospital Eye Centre (MURHEC) and Ruharo Eye Hospitals (REH) in Mbarara, Uganda. 6 Patient and public involvement Patients or the public were not involved in the design, or conduct, or reporting, or dissemination plans of our research.…”