Skip to main content

Table 4 Skin and soft tissue infections with microbiologic testing, Kaiser Permanente of Northern California, 20092011 a

From: Incidence, microbiology, and patient characteristics of skin and soft-tissue infections in a U.S. population: a retrospective population-based study

SSTI episodes with microbiologic testing 108,243 (100)
  Any pathogen identified by micriobiology test 58,794 (54)
  Specimen typeb  
   Blood 14,761 (14)
   Other 93,482 (86)
Microbiology results: Among episodes with culture-confirmed pathogenc  
  MRSA 21,890 (37)
  MSSA 25,628 (44)
  BHS 5,729 (10)
  Other streptococci 72 (<1)
  Other gram positive bacteria 923 (2)
  Gram negative bacteria 7,955 (14)
  Anaerobic bacteria 101 (<1)
  1. a Only SSTIs with a microbiology test are included in this table. Only tests performed on specimens obtained in the period from 7 days prior to the start of the SSTI episode to 7 days after the end of the SSTI episode were included. These tests were considered to have been performed to determine SSTI etiology. MRSA = methicillin-resistant S. aureus; MSSA = methicillin-sensitive S. aureus; BHS = beta-hemolytic streptococcus. Data are number (%) of cultured SSTI episodes, unless otherwise indicated.
  2. b Specimen type was the first positive specimen during the episode, or, if no specimens were positive, the first specimen. “Other” specimens include tissue, body fluid, and other miscellaneous bacterial specimens such as those taken from abscesses, pustules, boils, etc. Respiratory, CSF and urine cultures were excluded.
  3. c Denominator for percents is the number of episodes with any positive pathogen. Pathogen results are not mutually-exclusive. Over the study period 6% of first positive specimens were positive for multiple organisms. “Other streptococci” comprises S. pneumoniae, S. milleri, S. anginosus, S. constellatus, and S. intermedius. The following organisms were considered contaminants and not included: coagulase negative staphylococcus, ochrobactrum, corynebacterium, micrococcus spp., bacillus spp., gram positive cocci, gram positive rods, and streptococcus species other than BHS, S. pneumoniae, and “other streptococci” as defined above. ”BHS” comprises streptococci with Lancefield groups A, B, C and G.