Epidemiology, risk factors, and clinical outcomes in severe microbial keratitis in South India

Abstract

Purpose: Here, we report risk factors associated with outcome in severe bacterial keratitis (BK), fungal keratitis (FK), and Acanthamoeba keratitis (AK) in India. Methods: Prospective observational cohort study conducted in Aravind Eye Hospital, India. Adults presenting with severe microbial keratitis (MK) were enrolled (size ≥3 mm) and followed to 21 days post-enrolment. Ulcer clinical features were recorded at presentation. Outcomes by final visit were classified as good (completely healed or reduced infiltrate size) or poor (enlarged infiltrate size, perforated, or surgery performed). Results: Of 252 participants with severe MK, 191 had FK, 18 had AK, 19 had BK, 4 had mixed BK/FK, and 20 were microbiologically negative. Median age was 50 years (interquartile range [IQR]: 37–60 years), 64% were male, 63% were agriculturalists, and 45% had no formal education. Corneal trauma occurred in 72%, and median symptom duration before presentation was 7 days (IQR: 5–15 days). Clinical features associated with FK were feathery margins (p < 0.001), raised profile (p = 0.039), or dry surface (p = 0.007). Hypopyon was more likely in BK (p = 0.001) and ring infiltrate in AK (p < 0.001). Ulcers with poor outcome (n = 106/214) were more likely to be larger (odds ratio [OR]: 1.63, 95% confidence interval [CI]: 1.30–2.05, p < 0.001), involve the posterior cornea at presentation (OR: 2.31, 95% CI: 1.16–4.59, p = 0.017), involve Aspergillus sp. (OR: 3.23, 95% CI: 1.26–8.25, p = 0.014), or occur in females (OR: 2.04, 95% CI: 1.03–4.04, p = 0.04). Even after treatment, 34% (n = 76/221) had severe visual impairment by the final visit. Conclusions: Severe MK occurred predominantly in agriculturalists post-corneal trauma and often had poor outcomes. Provision of community-based eyecare may allow earlier treatment and improve outcomes.

Epidemiology of Microbial Keratitis in Uganda: A Cohort Study

“…As reported previously, severity of infection at presentation (vision, perforation status, and infiltrate size) was the strongest predictor of outcome. 23,25,26 Poor vision at presentation (WHO Snellen categories) was strongly associated with a worse visual outcome. Vision is an easily measurable and reliable prognostic measure that can support lower and mid-level cadres to make the right clinical decisions.…”

“…A large infiltrate size was associated with increased odds of a worse final visual outcome. 25,26 Most of the affected patients were aged between 31 and 60 years, which are the prime years for economic productivity. 13 About 70% of the affected people were heads of households and sole breadwinners in their home.…”

Characterization of Ocular Clinical Isolates of Pseudomonas aeruginosa from Non-Contact Lens Related Keratitis Patients from South India

“…aeruginosa, a Gram-negative bacterium, is ubiquitous in nature and a major opportunistic human pathogen. It is one of the most common causative agents for bacterial keratitis in India and worldwide [1]. P. aeruginosa adheres to the cell surface and releases toxins that result in recruitment of inflammatory cells leading to corneal scarring [2,3] that may lead to perforation of the cornea within 48-96 h of infection [4].…”

Risk Factors of Microbial Keratitis in Uganda: A Case Control Study

“…17,35 These levels appear to be lower than those reported from South Asia, where the proportion of MK cases associated with an injury is typically around 75%. 11,36,37 The reason for this difference is not immediately apparent. Perhaps eye trauma was either not as common in SSA as South Asia or it was too subtle to be recalled.…”