Risk factors, clinical features and outcomes of Neisseria keratitis.

OBJECTIVE: To describe the clinical features, risk factors and outcomes of Neisseria keratitis. METHODS: This is a retrospective observational study wherein medical records of cases with microbiologically proven Neisseria keratitis were reviewed. Data pertaining to the underlying predisposing factors, clinical characteristics of the corneal ulcer, antibiotic susceptibility of the Neisseria species isolate from the corneal scraping, the treatment given, and outcomes were collected and analyzed. RESULTS: Medical records of 60 patients (60 eyes) with Neisseria keratitis were reviewed. Among the causes of poor ocular surface as predisposing factor, vernal keratoconjunctivitis (n = 6 eyes), along with use of topical corticosteroids (n = 18 eyes) was the most common. The ulcer was characterized by a central infiltrate (31/60, 51.7%) involving up to the mid-stroma (43/60, 71.7%). Of the forty-four (73.3%) eyes with pure Neisseria keratitis, 31 eyes (72.1%) resolved with medical therapy alone while five eyes (11.6%) underwent therapeutic penetrating keratoplasty and in two (4.6%) eyes evisceration was performed. The other 5/44 (11.6%) patients were lost to follow-up. Resolution with medical therapy was found to be similar in cases with pure infection and mixed infection (p = 0.58). CONCLUSIONS: Neisseria keratitis most commonly causes a mild form of keratitis and is often associated with the poor ocular surface or prior steroid use. In most cases medical therapy is sufficient for complete resolution of the keratitis.

Clinical and Microbiological Spectra and Therapeutic Outcomes of Polymicrobial Keratitis.

PURPOSE: The aim of this study was to evaluate the risk factors, microbiology, and treatment outcomes of polymicrobial keratitis (PMK). METHODS: We retrospectively analyzed 65 patients diagnosed with PMK between 2016 and 2019. The clinical and microbiological characteristics and outcomes were evaluated. The primary outcome measure was clinical resolution of keratitis. Absolute success (group A) was defined as resolution of infection with medical treatment, qualified success (group B) was resolution with medical therapy and additional minor procedures, and failure (group C) was defined as worsening of infection and presence of corneal melting or perforation requiring therapeutic penetrating keratoplasty or evisceration. RESULTS: Of 4764 cases of microbial keratitis, PMK was identified in 65 eyes of 65 patients (1.36%). Infiltrate was central in 60% (39 eyes). Predisposing factors were higher in group C and included uncontrolled diabetes mellitus in 25% (7/28), history of trauma/foreign body in 57.1% (16/28), and poor presenting visual acuity (0.9 for group A vs. 1.79 for group B vs. 3.00 logarithm of the minimum angle of resolution for group C; P = 0.02). Microbiological profiling revealed that a majority (95%: 62/65) had bacterial with fungal keratitis. High fluoroquinolone resistance was noted (57%; 34/59). Absolute success was achieved in 28.3% (17/60), qualified success in 16.6% (10/60), and treatment failure was noted in 55% (33/60). The final best corrected visual acuity in group A was significantly better than that in group B and C (0.44 vs. 3.00 vs. 2.78; P < 0.001). CONCLUSIONS: PMK is extremely rare but responds poorly to medical therapy. Bacterial with fungal etiology is predominant. Early surgical intervention to improve overall outcome is advocated.