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Clinical and Microbiological Spectra and Therapeutic Outcomes of Polymicrobial Keratitis
Anubha Rathi1, Khuraman Ramazanova1, Somasheila I Murthy1
1The Cornea Institute, LV Prasad Eye Institute, Hyderabad, India.
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.
Insights
Polymicrobial keratitis (PMK) is rare and often involves bacterial and fungal infections, leading to poor outcomes with medical treatment alone. Early surgical intervention is recommended for better results in these complex cases.
Area of Science:
- Ophthalmology
- Infectious Diseases
- Microbiology
Background:
- Polymicrobial keratitis (PMK) is a severe eye infection involving multiple microorganisms.
- Understanding its risk factors, microbial profile, and treatment outcomes is crucial for effective management.
Purpose of the Study:
- To evaluate the risk factors, microbiology, and treatment outcomes of polymicrobial keratitis (PMK).
Main Methods:
- Retrospective analysis of 65 patients diagnosed with PMK between 2016 and 2019.
- Evaluation of clinical and microbiological characteristics, treatment strategies, and outcomes.
- Categorization of outcomes into absolute success, qualified success, and failure based on infection resolution and need for surgical intervention.
Main Results:
- PMK accounted for 1.36% of microbial keratitis cases.
- Bacterial and fungal co-infection was predominant (95%), with high fluoroquinolone resistance (57%).
- Treatment failure occurred in 55% of cases, with predisposing factors including trauma and uncontrolled diabetes; visual acuity was significantly worse in treatment failure groups.
Conclusions:
- PMK is a rare but challenging condition with a high rate of treatment failure under medical management alone.
- The predominant bacterial and fungal etiology necessitates consideration of combined therapeutic approaches.
- Early surgical intervention is advocated to improve overall outcomes in polymicrobial keratitis.
