Table 2.
Microbiological data
| Cellulitis | Cutaneous abscess | All cases | |||||||
|---|---|---|---|---|---|---|---|---|---|
| Diabetes mellitus N = 112 |
No diabetes mellitus N = 335 |
P | Diabetes mellitus N = 55 |
No diabetes mellitus N = 268 |
P | Diabetes mellitus N = 167 |
No diabetes mellitus N = 603 |
P | |
| Any microbiological culture obtained a | 82 (73) | 234 (70) | 46 (84) | 239 (89) | 128 (77) | 473 (78) | |||
| Wound drainage or swab | 19 (17) | 36 (11) | 1 (2) | 8 (3) | 20 (12) | 44 (7) | |||
| Abscess material | 1 (1) | 3 (1) | 39 (71) | 205 (76) | 40 (24) | 208 (34) | |||
| Tissue b | 2 (2) | 17 (5) | 1 (2) | 8 (3) | 3 (2) | 25 (4) | |||
| Blood | 73 (65) | 212 (63) | 26 (47) | 121 (45) | 99 (59) | 333 (55) | |||
| Any microorganism identified c | 20 (18) | 39 (12) | 0.09 | 38 (69) | 197 (74) | 0.50 | 58 (35) | 236 (39) | 0.30 |
| Aerobic gram-positive | 15 (75) | 36 (92) | 0.11 | 37 (97) | 182 (92) | 0.48 | 52 (90) | 218 (92) | 0.59 |
| Staphylococcus aureus | 11 (55) | 26 (67) | 0.38 | 28 (74) | 132 (67) | 0.42 | 39 (67) | 158 (67) | 0.97 |
| Methicillin-susceptible | 4 (20) | 15 (38) | 0.15 | 12 (32) | 42 (21) | 0.17 | 16 (28) | 57 (24) | 0.59 |
| Methicillin-resistant | 5 (25) | 11 (28) | 1.00 | 14 (37) | 85 (43) | 0.47 | 19 (33) | 96 (41) | 0.27 |
| Susceptibility not performed | 2 (10) | 0 | 0.11 | 2 (5) | 5 (3) | 0.32 | 4 (7) | 5 (2) | 0.08 |
| Streptococcal species | 6 (30) | 15 (38) | 0.52 | 12 (32) | 69 (35) | 0.68 | 18 (31) | 84 (36) | 0.51 |
| β-hemolytic streptococcus | 3 (15) | 13 (33) | 0.13 | 6 (16) | 32 (16) | 0.94 | 9 (16) | 45 (19) | 0.53 |
| S. anginosus-milleri group | 1 (5) | 0 | 0.34 | 2 (5) | 29 (15) | 0.11 | 3 (5) | 29 (12) | 0.12 |
| Other α-hemolytic streptococcus | 2 (10) | 2 (5) | 0.60 | 4 (11) | 12 (6) | 0.30 | 6 (10) | 14 (6) | 0.25 |
| Other streptococcus | 0 | 0 | - | 1 (3) | 3 (2) | 0.51 | 1 (2) | 3 (1) | 0.59 |
| S. aureus or streptococci | 15 (75) | 35 (90) | 0.25 | 37 (97) | 182 (92) | 0.48 | 52 (90) | 217 (92) | 0.60 |
| Enterococcus species | 0 | 2 (5) | 0.54 | 0 | 4 (2) | 1.00 | 0 | 6 (3) | 0.60 |
| Aerobic gram-negative | 2 (10) | 7 (18) | 0.70 | 2 (5) | 21 (11) | 0.39 | 4 (7) | 28 (12) | 0.28 |
| Anaerobic organism(s) | 2 (10) | 3 (8) | 1.00 | 8 (21) | 30 (15) | 0.37 | 10 (17) | 33 (14) | 0.53 |
| Mixed skin or oral flora | 1 (5) | 1 (3) | 1.00 | 0 | 1 (1) | 1.00 | 1 (2) | 2 (1) | 0.48 |
| Other | 1 (5) | 3 (8) | 1.00 | 2 (5) | 3 (2) | 0.19 | 3 (5) | 6 (3) | 0.39 |
| Polymicrobial | 3 (15) | 17 (45) | 0.03 | 11 (29) | 47 (24) | 0.51 | 14 (24) | 64 (27) | 0.65 |
| Positive blood culture d | 4 (5) | 8 (4) | 0.51 | 2 (8) | 3 (2) | 0.21 | 6 (6) | 11 (3) | 0.24 |
Data presented as n (%).
a
Cultures were obtained at the discretion of the treating provider.
b
Includes two tissue aspirates and one joint aspirate.
c
For each individual organism, the denominator used to calculate the proportion is the number of cases where an organism was identified.
d
Analysis excludes blood cultures with growth of only coagulase-negative staphylococci, diphtheroids, or micrococcus; denominator includes only cases where blood cultures were performed.