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Table 1 Clinical and microbiological characteristics of bloodstream infections due to AmpC-producing Enterobacteriaceae in the Calgary Zone

From: Clinical and microbiological characteristics of bloodstream infections due to AmpC β-lactamase producing Enterobacteriaceae: an active surveillance cohort in a large centralized Canadian region

  Enterobacter spp. 1 Serratia spp. 2 Citrobacter spp. 3 Providencia & Morganella spp. 4 E. coli 5 Other 6
No. of episodes 255 73 51 39 30 10
Source of infection (no. episodes)       
  Biliary 46 2 6 2 3 4
  Bowel 18 5 4 4 2 0
  Urinary 43 10 13 15 5 2
  Pneumonia 14 13 2 0 1 0
  CVS source 0 1 0 0 0 0
  SST source 7 4 0 0 0 0
  BJ source 1 0 2 4 0 0
  CNS source 1 0 0 0 0 0
  Unknown 125 38 24 14 19 4
Comorbid conditions       
  Myocardial infarction 15 (5.9%) 4 (5.5%) 4 (7.8%) 4 (10%) 2 (6.7%) 0 (0%)
  CHF 32 (13%) 18 (25%) 5 (9.8%) 6 (15%) 2 (6.7%) 1 (10%)
  PVD 6 (2.4%) 7 (9.6%) 1 (2.0%) 4 (10%) 2 (6.7%) 1 (10%)
  CVD 8 (3.1%) 5 (6.8%) 1 (2.0%) 2 (5.1%) 0 (0%) 1 (10%)
  Dementia 2 (<1%) 0 (0%) 2 (3.9%) 3 (8.5%) 1 (3.3%) 0 (0%)
  CPD 20 (7.8%) 13 (18%) 2 (3.9%) 5 (13%) 8 (27%) 3 (30%)
  Rheumatic disease 2 (<1%) 0 (0%) 1 (2.0%) 3 (8.5%) 0 (0%) 0 (0%)
  Peptic ulcer disease 9 (3.5%) 4 (5.5%) 1 (2.0%) 2 (5.1%) 0 (0%) 1 (10%)
  Hemiplegia/Paraplegia 6 (2.4%) 4 (5.5%) 2 (3.9%) 3 (8.5%) 1 (3.3%) 0 (0%)
  Renal disease 31 (12%) 17 (23%) 7 (14%) 9 (23%) 2 (6.7%) 0 (0%)
  Mild liver disease 10 (3.9%) 1 (1.4%) 1 (2.0%) 0 (0%) 0 (0%) 0 (0%)
  Moderate severe liver disease 12 (4.7%) 4 (5.5%) 1 (2.0%) 2 (5.1%) 2 (6.7%) 1 (10%)
  Malignancy 53 (21%) 8 (11%) 15 (29%) 2 (5.1%) 1 (3.3%) 2 (20%)
  Metastatic solid cancer 27 (11%) 3 (4.1%) 2 (3.9%) 1 (2.6%) 5 (17%) 1 (10%)
  DM w/o complication 25(9.8%) 7 (9.6%) 2 (3.9%) 4 (10%) 3 (10%) 0 (0%)
  DM w/ complications 14 (5.5%) 6 (8.2%) 3 (5.9%) 6 (15%) 1 (3.3%) 0 (0%)
Median Charlson (IQR) 3 (1–5) 4 (2–6) 3 (2–4) 4 (3–7) 4 (1–5) 4 (4–6)
Median age (IQR) 58.0 (39 – 72.3) 65.6 (52.1 – 74.2) 59.1 (36.6 – 75.3) 72.9 (62.9 – 79.6) 58.6 (41.1 – 77.3) 71.2 (64.4 – 81.6)
Male sex (%) 62% 60% 75% 74% 33% 50%
Surveillance definition       
  Nosocomial 138 (24, 17% ) 45 (14, 31%) 22 (1, 4.5%) 13 (2, 15%) 11 (0, 0%) 3 (0, 0%)
  HCAI 70 (6, 8.6%) 12 (1, 8.3%) 16 (0, 0%) 17 (3, 18%) 10 (1, 10%) 4 (0, 0%)
  Community acquired 47 (3, 6.4%) 16 (3, 19%) 13 (0, 0%) 9 (1, 11%) 9 (0, 0%) 3 (1, 33%)
  p-value 0.08 0.248 1.000 1.000 0.633 0.600
Per year of infection       
  2000 20 (7.8%) 6 (8.2%) 2 (3.9%) 7 (18%) 0 (0%) 1 (10%)
  2001 26 (10%) 13 (18%) 3 (5.9%) 0 (0%) 4 (13%) 3 (30%)
  2002 24 (9.4%) 5 (6.9%) 5 (9.8%) 1 (2.6%) 4 (13%) 1 (10%)
  2003 33 (13%) 3 (4.1%) 3 (5.9%) 9 (23%) 5 (17%) 2 (20%)
  2004 31 (12%) 9 (12%) 8 (16%) 3 (7.7%) 2 (6.7%) 2 (20%
  2005 20 (7.8%) 14 (19%) 8 (16%) 8 (21%) 2 (6.7%) 1 (10%)
  2006 24 (9.4%) 6 (8.2%) 5 (9.8%) 5 (13%) 7 (23%) 0 (0%)
  2007 31 (12%) 7 (9.6%) 10 (20%) 2 (5.1%) 2 (6.7%) 0 (0%)
  2008 46 (18%) 10 (14%) 7 (14%) 4 (10%) 4 (13%) 0 (0%)
Susceptibility testing (percentage susceptible)       
  Ciprofloxacin 248/255 (98%) 71/73 (97%) 47/50 (94%) 36/38 (95%) 24/30 (80%) 10/10 (100%)
  Gentamicin 251/255 (99%) 72/73 (99%) 45/50 (90%) 34/38 (90%) 23/30 (77%) 10/10 (100%)
  Piperacillin-tazobactam 203/255 (80%) 69/73 (95%) 46/50 (92%) 38/38 (100%) 29/30 (97%) 7/10 (70%)
  TMP/SMX 242/255 (95%) 73/73 (100%) 39/50 (78%) 31/38 (82%) 19/30 (63%) 10/10 (100%)
  Tobramycin 251/255 (99%) 64/73 (88%) 45/50 (90%) 33/38 (87%) 26/30 (87%) 10/10 (100%)
  Imipenem 255/255 (100%) 73/73 (100%) 50/50 (100%) 38/38 (100%) 30/30 (100%) 10/10 (100%)
  1. 1Includes 34 E. aerogenes, 1 E. asburiae, 2 E. cancerogenus, 210 E. cloacae, 6 E. sakazakii and 2 E. spp bacteremia episodes.
  2. 2Includes 3 S. liquefaciens, 67 S. marcescens, 1 S. odorfera and 2 S. spp. bacteremia episodes.
  3. 3Includes 17 C. braakii, 30 C. freundii, 2 C. spp. and 2 C. youngae bacteremia episodes.
  4. 4Includes 27 M. Morganii, 3 P. rettgeri and 9 P. stuartii bacteremia episodes.
  5. 5Includes 30 E. coli bacteremia episodes.
  6. 6Includes 7 H. alveii, 2 Salmonella spp. and 1 K. pneumoniae bacteremia episodes.
  7. CVS = Cardiovascular, SST = Skin and Soft Tissue, BJ = Bone and Joint, CNS = Central Nervous System, CHF = Congestive Heart Failure, PVD = Peripheral Vascular Disease, CVD = Cerebrovascular Disease, CPD = Chronic Pulmonary Disease, TMP/SMX = Trimethoprim/Sulfamethoxazole.