TABLE 1.
Univariate analysis of patients with PVL-positive MSSA infection versus PVL-negative MSSA infection
| Patient characteristic | No. (%) of PVL-positive patients (n = 124) | No. (%) of PVL-negative patients (n = 211) | OR (95% CI) of PVL-positive compared to PVL-negative patients | P value of PVL-positive compared to PVL-negative patients |
|---|---|---|---|---|
| Female gender | 55 (44) | 98 (46) | 0.92 (0.59-1.44) | 0.73 |
| Ethnicitya | ||||
| European | 41 (33) | 116 (55) | 0.40 (0.25-0.64) | <0.0001 |
| Maori | 22 (18) | 22 (10) | 1.85 (0.98-3.51) | 0.09 |
| Pacific | 50 (40) | 46 (22) | 2.42 (1.49-3.94) | 0.0007 |
| Asian | 4 (3) | 17 (8) | 0.38 (0.13-1.16) | 0.10 |
| Other | 7 (6) | 10 (5) | 1.20 (0.45-3.24) | 0.14 |
| Age (yr)a,b | ||||
| 0-9 | 40 (33) | 55 (26) | 1.35 (0.83-2.20) | 0.21 |
| 10-19 | 27 (22) | 23 (11) | 2.28 (1.24-4.18) | 0.01 |
| 20-29 | 11 (9) | 18 (9) | 1.04 (0.48-2.29) | 0.99 |
| 30-39 | 17 (14) | 18 (9) | 1.70 (0.84-3.44) | 0.14 |
| 40-49 | 13 (11) | 18 (9) | 1.66 (0.59-2.66) | 0.56 |
| 50-59 | 1 (1) | 15 (7) | 0.11 (0.11-0.81) | 0.007 |
| 60-69 | 10 (8) | 22 (11) | 0.75 (0.34-1.65) | 0.57 |
| 70-79 | 1 (1) | 23 (11) | 0.07 (0.01-0.50) | 0.0003 |
| 80-89 | 1 (1) | 16 (8) | 0.10 (0.01-0.76) | 0.008 |
| NZDep2006 scorec | ||||
| 1-3 (low deprivation) | 22 (18) | 52 (25) | 0.66 (0.38-1.15) | 0.17 |
| 4-7 (medium deprivation) | 42 (34) | 69 (33) | 1.05 (0.65-1.68) | 0.90 |
| 8-10 (high deprivation) | 58 (48) | 86 (42) | 1.28 (0.81-2.00) | 0.30 |
| Source of infectiona | ||||
| Skin and soft tissue infection | 112 (90) | 122 (58) | 6.81 (3.54-13.11) | <0.0001 |
| Surgical site infection | 2 (2) | 34 (16) | 0.09 (0.02-0.36) | <0.0001 |
| Catheter-related infection | 1 (1) | 12 (6) | 0.13 (0.02-1.05) | 0.04 |
| Bone and joint infection | 4 (3) | 9 (4) | 0.75 (0.23-2.48) | 0.78 |
| Pneumonia | 2 (2) | 9 (4) | 0.37 (0.08-1.73) | 0.22 |
| Primary bacteremia or endocarditis | 0 (0) | 6 (3) | ||
| Other | 3 (2) | 19 (9) | 0.25 (0.07-0.86) | 0.02 |
| Onseta | ||||
| Community onset, not health care associated | 69 (56) | 79 (37) | 2.10 (1.34-3.29) | 0.001 |
| Community onset, health care associated | 43 (35) | 52 (25) | 1.62 (1.00-2.64) | 0.06 |
| Hospital onset, health care associated | 12 (10) | 80 (38) | 0.18 (0.09-0.34) | <0.0001 |
| Comorbidities (Charlson score of <3) | 112 (90) | 155 (73) | 3.37 (1.73-6.58) | 0.0002 |
| Implanted medical device | 3 (2) | 23 (11) | 0.20 (0.06-0.69) | 0.005 |
| Trauma with breach of skin <30 days | 19 (15) | 21 (10) | 1.64 (0.84-3.18) | 0.16 |
| Chronic noninfective skin condition | 6 (5) | 32 (15) | 0.28 (0.12-0.70) | 0.004 |
| Required surgical procedurea | 75 (60) | 59 (28) | 3.94 (2.47-6.30) | <0.0001 |
| ≥2 surgical procedures | 4/75 (5) | 10/59 (17) | 0.28 (0.08-0.93) | 0.04 |
| Presence of bacteremia | 4/35 (11) | 19/92 (21) | 0.50 (0.16-1.58) | 0.43 |
| Duration of admission (days) | ||||
| ≤1 | 45 (36) | 72 (34) | 1.1 (0.69-1.75) | 0.73 |
| 2-4 | 63 (51) | 46 (22) | 6.00 (3.40-10.59) | <0.0001 |
| ≥5 | 16 (13) | 93 (44) | 0.19 (0.10-0.34) | <0.0001 |
| Readmitted within 30 days | 6 (5) | 9 (4) | 1.14 (0.40-3.29) | 0.79 |
| 30-day mortality | 1 (1) | 10 (5) | 0.16 (0.02-1.29) | 0.06 |
a
Found to be independent associations upon multivariate analysis adjusted for gender, ethnicity, age, deprivation score, onset, comorbidities, implanted medical device, trauma with breach of skin, chronic noninfective skin conditions, surgical requirement, duration of admission, 30-day readmission, and 30-day mortality.
b
Six patients aged greater than 90 years were excluded from analysis due to low numbers.
c
NZDep2006 score was not available for six patients.