Table 1.
Epidemiologic characteristics and predisposing factors of Pseudomonas aeruginosa and P. putida keratitis
| Characteristics |
P. aeruginosa
(n = 33) |
P. putida
(n = 16) |
p-value (x2-test) |
|---|---|---|---|
| Male sex | 16 (48.5) | 7 (43.8) | 0.755 |
| Age, mean ± SD, years | 47.0 ± 24.4 | 59.3 ± 18.9 | 0.060† |
| Age subgroup | |||
| 0–19 | 2 (6.1) | 1 (6.3) | 1.000* |
| 20–39 | 14 (42.4) | 1 (6.3) | 0.018* |
| 40–59 | 4 (12.1) | 6 (37.5) | 0.060* |
| ≥ 60 | 13 (39.4) | 8 (50.0) | 0.482 |
| Symptom duration‡ | |||
| mean ± SD, days | 4.3 ± 3.9 | 9.5 ± 7.8 | 0.022† |
| > 5 days | 8 (24.2) | 11 (68.8) | 0.003 |
| Duration of hospitalization§, | |||
| mean ± SD, days | 10.4 ± 6.4 | 8.6 ± 4.9 | 0.325† |
| Seasonal distribution | |||
| Spring (Mar-May) | 7 (21.2) | 2 (12.5) | 0.698* |
| Summer (Jun-Aug) | 6 (18.2) | 6 (37.5) | 0.169* |
| Autumn (Sep-Nov) | 15 (45.5) | 3 (18.8) | 0.069 |
| Winter (Dec-Feb) | 5 (15.2) | 5 (31.3) | 0.261* |
| Predisposing factors | |||
| Corneal trauma | 9 (27.3) | 10 (62.5) | 0.018 |
| Contact-lens wear | 12 (36.4) | 0 (0.0) | 0.005* |
| Previous OSD# | 7 (21.2) | 6 (37.5) | 0.304* |
| Previous ocular surgery¶ | 5 (15.2) | 3 (18.8) | 1.000* |
| Previous topical antibiotics use | 12 (36.4) | 8 (50.0) | 0.362 |
| Previous topical steroid use | 5 (15.2) | 0 (0.0) | 0.158* |
| Systemic disease** | 10 (30.3) | 7 (43.8) | 0.354 |
| No apparent cause | 8 (24.2) | 4 (25.0) | 1.000* |
SD standard deviation, OSD ocular surface disease
Values indicate numbers (proportion) unless otherwise noted
*The p-value was calculated using Fisher’s exact test
†The p-value was calculated using independent t-test
‡Interval from the onset of symptoms to the time of initial presentation
§The period from admission to discharge
#P. aeruginosa group included necrotizing scleritis (two cases), exposure keratopathy (two cases), neurotrophic keratopathy (one case), bullous keratopathy (one case), and previous corneal ulcer (one case); P. putida group included exposure keratopathy (two cases), pseudophakic bullous keratopathy (one case), leukoma adherence (one case), herpetic keratitis (one case), and recurrent erosion syndrome (one case)
¶P. aeruginosa group included cataract surgery (four cases) and pars plana vitrectomy due to proliferative diabetic retinopathy (one case); P. putida group included cataract surgery (two cases) and Ahmed valve implantation due to neovascular glaucoma (one case)
**P. aeruginosa group included hypertension only (four cases), diabetes mellitus (three cases), cardiovascular abnormality with hypertension (two cases), and cardiovascular abnormality only (one case). P. putida group included hypertension only (three cases), diabetes mellitus with hypertension (one case), hepatitis B with hypertension (one case), rheumatoid arthritis (one case), and atrial septal defect (one case)