Table 1.
Characteristics of clinically-diagnosed skin and soft tissue infection episodes, Kaiser Permanente of Northern California, 2009–2011 a
| All episodes | 471,550 (100) |
|---|---|
| Type of SSTI |
|
| Carbuncle and furuncle |
24,238 (5) |
| Impetigo |
37,075 (8) |
| Other infections of the skin |
31,870 (7) |
| Folliculitis |
69,000 (15) |
| Other SSTI |
11,331 (2) |
| Cellulitis and abscess |
298,036 (63) |
| Gender |
|
| Female |
249,844 (53) |
| Male |
221,706 (47) |
| Age in years |
|
| Under 5 |
32,384 (7) |
| 5- < 18 |
73,779 (16) |
| 18- < 50 |
185,103 (39) |
| 50- < 65 |
97,277 (21) |
| 65+ |
83,007 (18) |
| Mean age (std) |
40.82 (24) |
| Race/ethinicity |
|
| Asian |
55,595 (12) |
| African-American |
43,407 (9) |
| Hispanic |
96,626 (20) |
| Native American |
2,967 (1) |
| Multiracial |
18,449 (4) |
| White |
254,507 (54) |
| Microbiology test performedb |
108,243 (23) |
| Any pathogen identified by microbiology test | 58,794 (12) |
a Episodes were defined as beginning on the date of the first skin and soft tissue infection (SSTI) diagnosis and ending with the last SSTI or SSTI-related complication diagnosis, not followed by another SSTI or SSTI complication diagnosis within 42 days. Duration of health services use was calculated as the number of days from the start of the episode to the end of the episode. Values in columns are number of episodes and percent of all episodes, unless otherwise indicated.
b Microbiology tests included in analyses were those performed on blood, tissue, body fluid or other miscellaneous bacterial specimens (such as those taken from abscesses, pustules, boils, etc.) obtained from the patient within 7 days prior to the beginning of the SSTI episode to 7 days after the end of the episode. Respiratory, cerebrospinal fluid and urine specimens were excluded. These microbiology tests were considered to have been performed to determine SSTI etiology. A minority of episodes received such testing.