Article Figures & Data
Tables
- TABLE 1.
Characteristics of diabetic foot specimens taken prior to antimicrobial therapy
Characteristic Value Total no. of specimens 454 No. (%) with aerobes only 222 (48.9) No. (%) with anaerobes only 6 (1.3) No. (%) with mixed growth 199 (43.8) No. (%) with no growth 27 (5.9) No. of positive cultures 427 No. of patients with positive cultures 406 No. (%) of positive cultures with: One isolate 69 (16.2) Two isolates 87 (20.4) Three isolates 84 (19.7) Four isolates 57 (13.3) More than four isolates 130 (30.4) Total no. of aerobes 1,145 No. of different species 115 Range of no. of aerobes per specimen 0-8 Avg no. of aerobes per positive specimen 2.7 No. (%) of positive specimens in pure culture 64 (15.2) Total no. of anaerobes 462 No. of different species 74 Range of no. of anaerobes per specimen 0-9 Avg no. of anaerobes per positive specimen 2.3 No. (%) of positive specimens in pure culture 3 (1.5) Total no. of all isolates 1,607 - TABLE 2.
Comparative frequency of groups of species by specimen collection type
Organism No. of isolates (% of specimens yielding the groupa) obtained by or with: Total (n = 454) Aspiration (n = 52 [11.5b]) Swab (n = 132 [29.1]) Tissue (n = 258 [56.8]) Not specified (n = 12 [2.6]) Aerobes Nonfermenting gram-negative rods 35 (7.7) 5 (9.6) 10 (7.6) 18 (7.0) 2 (16.7) Pseudomonas spp. 42 (9.3) 3 (5.8) 15 (11.4) 24 (9.3) 0 Enterobacteriaceae group 147 (32.4) 16 (30.8) 45 (34.1) 85 (32.9) 1 (8.3) Corynebacterium spp. 116 (25.6) 7 (13.5) 32 (24.2) 72 (27.9) 5 (41.7) Miscellaneous gram-positive rods 53 (11.7) 3 (5.8) 18 (13.6) 32 (12.4) 0 Enterococcus spp. 154 (33.9) 10 (19.2) 56 (42.4) 84 (32.6) 4 (33.3) Staphylococcus spp. 388 (85.5) 34 (65.4) 107 (81.1) 237 (91.9) 10 (83.3) S. aureus, Ox-Rc 53 (11.7) 4 (7.7) 20 (15.2) 24 (9.3) 1 (8.3) S. aureus, Ox-Sd 164 (36.1) 22 (42.3) 46 (34.8) 93 (36.0) 3 (25.0) S. epidermidis 72 (15.9) 2 (3.8) 21 (15.9) 47 (18.2) 2 (16.7) S. epidermidis, Ox-R 15 (3.3) 0 6 (4.5) 9 (3.5) S. haemolyticus 22 (4.8) 1 (1.9) 4 (3.0) 16 (6.2) 1 (8.3) S. lugdunensis 22 (4.8) 1 (1.9) 4 (3.0) 14 (5.4) 3 (25.0) Other coagulase-negative staphylococci 36 (7.9) 3 (5.8) 7 (5.3) 26 (10.1) Streptococcus spp. 190 (41.9) 23 (44.2) 48 (36.4) 110 (42.6) 9 (75.0) Anaerobes Bacteroides fragilis group 55 (12.1) 4 (7.7) 16 (12.1) 32 (12.4) 3 (25.0) Fusobacterium spp. 11 (2.4) 1 (1.9) 3 (2.3) 7 (2.7) Porphyromonas spp. 53 (11.7) 4 (7.7) 12 (9.1) 37 (14.3) Prevotella spp. 64 (14.1) 2 (3.8) 15 (11.4) 46 (17.8) 1 (8.3) Anaerobic cocci 219 (48.2) 14 (26.9) 65 (49.2) 133 (51.6) 7 (58.3) Clostridium spp. 20 (4.4) 3 (5.8) 7 (5.3) 10 (3.9) Non-spore-forming, gram-positive rods 43 (9.5) 2 (3.8) 11 (8.3) 29 (11.2) 1 (8.3) - TABLE 3.
Distribution of 462 anaerobes and 1,145 aerobes isolated from DFIs
Organism No. isolated % Total aerobes or anaerobes % in genus % Total isolates No. (%) of patientsa No. (%) in pure culture All gram-positive aerobes 920 80.3 57.1 394 (97.0) 63 (6.8) Staphylococcus spp. 389 34.0 24.1 328 (80.8) OSSAb 164 14.3 42.2 10.2 162 (39.9) 26 (15.9) ORSAc 50 4.4 12.9 3.1 48 (11.8) 10 (20) S. epidermidis (15 MRSEd strains) 87 7.6 22.4 5.4 81 (20.0) 8 (9.2) S. lugdunensis 22 1.9 5.7 1.4 22 (5.4) 2 (9.1) S. haemolyticus 22 1.9 5.7 1.4 20 (4.9) 1 (4.5) S. simulans 12 1.0 3.1 0.7 12 (3.0) 2 (16.7) Other Staphylococcus spp. 32 2.8 8.2 2.0 31 (7.6) 2 (9.4) Streptococcus spp. 177 15.5 10.5 168 (41.1) S. agalactiae 86 7.5 48.6 5.2 82 (20.2) 3 (3.5) S. mitis group 41 3.6 23.2 2.5 38 (9.4) 2 (4.9) S. milleri group 19 1.7 10.7 1.1 17 (4.2) S. dysgalactiae subsp. equisimilis 18 1.6 10.2 1.1 18 (4.4) Other Streptococcus spp., including S. pyogenes (n = 3) 13 1.1 7.3 1.1 13 (3.2) Miscellaneous gram-positive cocci 27 2.4 1.7 1 (3.7) Enterococcus spp. 155 13.5 9.6 145 (35.7) E. faecalis 138 12.1 89.0 8.6 128 (31.5) 1 (0.7) Other Enterococcus spp. 17 1.5 11.0 1.1 17 (4.2) 1 (5.9) Corynebacterium spp. 116 10.1 7.2 115 (28.3) C. amycolatum 49 4.3 42.2 3 46 (11.3) 1 (2.0) C. striatum 30 2.6 25.9 1.9 29 (7.1) Other Corynebacterium spp. 37 3.2 31.9 2.3 37 (9.1) 1 (2.7) Dermabacter hominis 15 1.3 11.5 0.9 15 (3.4) Actinomyces-Arcanobacterium group 13 1.1 Other gram-positive rods 25 2.2 1 (4.0) All gram-negative aerobic organisms 225 19.7 14.0 145 (35.7) 3 (1.3) Escherichia coli 20 1.7 8.9 1.2 20 (4.9) Klebsiella spp. 25 2.2 11.1 1.6 25 (6.2) Enterobacter cloacae 20 1.7 8.9 1.2 20 (4.9) 1 (5.0) Enterobacter-Citrobacter-Pantoeae group 16 1.4 7.1 1.0 13 (3.2) 1 (6.3) Serratia marcescens 14 1.2 6.2 0.9 14 (3.4) Proteus-Providencia-Morganella group 28 2.4 12.4 1.7 25 (6.2) Proteus mirabilis 24 2.1 10.7 1.5 23 (5.7) Pseudomonas aeruginosa 40 3.5 17.8 2.5 35 (8.6) 1 (2.5) Stenotrophomonas maltophilia 15 1.3 6.7 0.9 15 (3.7) Alcaligenes faecalis group 10 0.9 4.4 0.6 9 (2.2) Other nonfermenting gram-negative rods 13 1.1 5.8 0.8 13 (3.2) All anaerobic organisms 462 28.7e 199 (49.0) 3 (0.6) Bacteroides fragilis group 47 10.2 2.9 34 (8.4) B. fragilis 19 4.1 40.4 B. caccae 2 0.4 4.3 B. distasonis 1 0.2 2.1 B. ovatus 5 1.1 10.6 B. stercoris 2 0.4 4.3 B. thetaiotaomicron 8 1.7 17.0 B. uniformis 5 1.1 10.6 B. vulgatus 5 1.1 10.6 Prevotella spp. 63 13.6 3.9 50 (12.3) P. melaninogenica 11 2.4 17.2 10 (2.5) Prevotella spp., pigmented 10 2.2 15.6 Prevotella bivia 26 5.8 41.3 26 (6.4) Prevotella spp., nonpigmented 16 3.5 25.0 Porphyromonas spp. 52 11.3 3.3 42 (10.3) P. asaccharolytica 29 6.3 55.8 28 (6.9) P. somerae (formerly P. levii) 21 4.5 39.6 20 (4.9) Other Porphyromonas spp. 2 0.4 3.8 Fusobacterium spp. 11 2.4 0.7 10 (2.5) F. nucleatum 8 1.7 72.7 F. mortiferum-F. varium group 3 0.6 27.2 Other gram-negative species 13 2.8 0.8 Anaerobic gram-positive cocci 209 45.2 13.0 152 (37.4) Finegoldia magna 102 22.1 48.8 6.4 99 (24.4) Peptoniphilus asaccharolyticus 37 8.0 17.7 37 (9.1) Peptostreptococcus anaerobius 15 3.2 7.2 14 (3.4) Anaerococcus prevotii 13 2.8 6.2 13 (3.2) 1 (7.7) Anaerococcus tetradius 9 1.9 4.3 9 (2.2) Peptostreptococcus micros 6 1.3 2.9 6 (1.5) Other species 27 5.8 12.9 27 (6.7) Clostridium spp. 20 4.3 1.2 20 (4.9) C. innocuum 1 0.2 5.0 C. clostridioforme group 3 0.6 15.0 C. perfringens 6 1.3 30.0 Other Clostridium spp. 10 2.1 50.0 Eubacterium group 17 3.7 1.1 17 (4.2) Other gram-positive, non-spore-forming rodsf 30 6.5 1.9 2 (6.7) - TABLE 4.
In vitro activities of antimicrobial agents against gram-positive aerobic organisms
Organism (no. of isolates) MIC50/MIC90 (μg/ml [% susceptible])a ETP P/T A/C CFL CIP LVX MXF DOX CM T/S Corynebacterium amycolatum (49) 2/>16 (69) ≤2/>32 (78) ≤1/>8 (78) ≤2/>32 (55) 8/>8 (27) 8/>8 (27) 2/>4 (57) ≤2/16 (80) 8/>8 (10) 2/>4 (51) Corynebacterium spp. and other non-spore-forming gram-positive rodsb (120) ≤0.25/2 (93) ≤2/>32 (78) ≤1/4 (91) ≤2/>32 (74) 4/>8 (50) 2/>8 (54) 0.5/>4 (74) ≤2/8 (87) 8/>8 (30) 4/>4 (49) Enterococcus spp.c (155) 8/16 (10) ≤2/>32 (97) ≤1/≤1 (99) >32/>32 (5) 1/>8 (68) 1/>8 (77) 0.5/>4 (80) 4/8 (63) >8/>8 (1) ≤0.5/4 (90) Staphylococcus aureus, Ox-Rd (49) 4/>16 (NIe) 8/32 (NI) 8/>8 (NI) >32/>32 (NI) >8/>8 (12) >8/>8 (16) 4/>4 (16) ≤2/≤2 (94) >8/>8 (47) ≤0.5/≤0.5 (90) S. aureus, Ox-Sf (169) ≤0.25/≤0.25 (100) ≤2/≤2 (100) ≤1/≤1 (100) ≤2/4 (99) ≤0.5/1 (94) ≤0.5/≤0.5 (96) ≤0.25/≤0.25 (95) ≤2/≤2 (95) ≤0.25/≤0.25 (98) ≤0.5/≤0.5 (98) S. epidermidis (89) 2/8 (87) ≤2/≤2 (97) ≤1/2 (99) 16/32 (37) ≤0.5/>8 (54) ≤0.5/8 (57) ≤0.25/2 (63) ≤2/8 (90) ≤0.25/>8 (89) ≤0.5/>4 (67) S. haemolyticus (22) 2/>16 (68) ≤2/>32 (68) ≤1/>8 (68) >32/>32 (14) >8/>8 (18) 8/>8 (23) 1/>4 (23) ≤2/32 (55) ≤0.25/>8 (77) ≤0.5/>4 (68) S. lugdunensis (23) ≤0.25/≤0.25 (100) ≤2/≤2 (100) ≤1/≤1 (100) 4/16 (83) ≤0.5/≤0.5 (100) ≤0.5/≤0.5 (100) ≤0.25/≤0.25 (100) ≤2/≤2 (100) ≤0.25/≤0.25 (91) ≤0.5/≤0.5 (100) Coagulase-negative Staphylococcus spp.g (44) 0.5/4 (93) ≤2/≤2 (98) ≤1/2 (100) ≤2/>32 (77) ≤0.5/>8 (80) ≤0.5/>8 (82) ≤0.25/4 (82) ≤2/4 (96) ≤0.25/>8 (84) ≤0.5/1 (91) Streptgcoccus spp.h (173) ≤0.25/≤0.25 (100) ≤2/≤ (100) ≤1/≤1 (99) ≤2/8 (93) ≤0.5/4 (71) ≤0.5/2 (97) ≤0.25/0.5 (97) 8/16 (40) ≤.25/>8 (90) ≤0.5/≤0.5 (95) ↵ a ETP, ertapenem; P/T, piperacillin-tazobactam; A/C, amoxicillin-clavulanic acid; CFL, cephalexin; CIP, ciprofloxacin; LVX, levofloxacin; MXF, moxifloxacin; DOX, doxycycline; CM, clindamycin; T/S, trimethoprim-sulfamethoxazole.
↵ b Corynebacterium striatum (n = 31), Corynebacterium accolens (n = 1), Corynebacterium aurimucosum (n = 5), Corynebacterium glucuronolyticum (n = 2), Corynebacterium jeikeium (n = 5), Corynebacterium minutissimum (n = 1), Corynebacterium pseudodiphtheriticum (n = 1), “Corynebacterium pseudogenitalium” (n = 2), Corynebacterium pseudotuberculosis (n = 1), Corynebacterium simulans (n = 4), Corynebacterium tuberculostearicum (n = 7), Corynebacterium urealyticum (n = 1), Corynebacterium xerosis (n = 4), Corynebacterium spp. (n = 2), Dermabacter hominis (n = 15), Actinobaculum massiliae (n = 1), Actinomyces neuii subsp. anitratus (n = 2), A. neuii subsp. neuii (n = 1), A. turicensis (n = 2), Arcanobacterium bernardiae (n = 5), Arcanobacterium hemolyticum (n = 3), Arthrobacter albus (n = 2), Arthrobacter creatinolyticus (n = 1), Bacillus cereus (n = 2), Bacillus pumilus (n = 2), Bacillus sp. (n = 1), Bifidobacterium urinalis (n = 1), Brachybacterium sp. (n = 1), Brevibacterium lutoleum (n = 1), Brevibacterium otitidis (n = 1), Brevibacterium spp. (n = 2), Lactobacillus gasseri (n = 1), Lactobacillus jensenii (n = 1), Microbacterium oxydans (2), Paenibacillus sp. (n = 1), Propionibacterium acnes (n = 1) and Propionibacterium avidum (n = 1) (both aerobic), “Zimmermannella bifida” (n = 1), and gram-positive bacilli with no sequence match (n = 2).
↵ c Enterococcus faecalis (n = 139), E. avium (n = 3), E. canis (n = 2), E. casseliflavus (n = 1), E. faecium (n = 5), E. gallinarum (n = 4), and Enterococcus sp. (n = 1).
↵ d Ox-S, oxacillin sensitive.
↵ e NI, no interpretation.
↵ f Ox-R, oxacillin resistant.
↵ g Staphylococcus. auricularis (n = 1), S. capitis (n = 2), S. caprae (n = 3), S. cohnii (n = 4), S. hominis (n = 5), S. schleiferi (n = 1), S. sciuri (n = 9), S. simulans (n = 12), S. warneri (n = 4), S. xylosus (n = 1), and Staphylococcus spp. with no sequence match (n = 2).
↵ h Streptococcus agalactiae (n = 85), S. anginosus (n = 17), S. bovis (n = 1), S. canis (n = 1), S. constellatus (n = 2), S. dysgalactiae subsp. equisimilis (n = 19). S. gordonii (n = 1), S. infantarius (n = 1), S. mitis group (n = 41), S. minor (n = 1), S. pyogenes (n = 3), and S. salivarius (n = 1).
- TABLE 5.
In vitro activities of antimicrobial agents against gram-negative aerobic organisms
Organism (no. of isolates) MIC50/MIC90 (μg/ml [% susceptible])a ETP IPM P/T A/C CFL CAZ CIP LVX MXF GM AMK DOX T/S Enterobacteriaceae groupb (98) ≤0.125/≤0.125 (99) 0.25/2 (100) ≤1/4 (96) 8/>64 (55) 8/>32 (52) ≤0.5/≤0.5 (94) ≤0.5/≤0.5 (94) ≤0.5/1 (94) ≤0.25/2 (94) ≤2/≤2 (95) ≤8/≤8 (99) 2/16 (79) ≤0.5/>4 (90) Proteus-Providencia-Morganella groupc (55) ≤0.125/≤0.125 (98) 4/4 (100) ≤1/≤1 (98) 8/>64 (58) ≤0.5/8 (93) ≤0.5/≤0.5 (95) ≤0.5/≤0.5 (95) ≤0.25/2 (91) ≤2/≤8 (98) ≤2/≤2 (100) >32/>32 (22) ≤0.5/>4 (91) P. aeruginosa (43) 8/16 (NId) 1/4 (86) 4/16 (98) 1/4 (98) ≤.5/1 (91) ≤.5/8 (79) 1/8 (74) ≤2/4 (95) ≤8/≤8 (100) S. maltophilia (15) >16 (NI) >16 (NI) >128/>128 (NI) 64/64 (NI) 8/>32 (53) 2/>8 (NI) 1/>8 (80) 0.5/4 (NI) >32/>32 (NI) 128/>128 (NI) 4/4 (NI) >4/>4 (20) Miscellaneous nonfermenting gram-negative rodse (24) ≤.125/>16 (63) 0.25/4 (92) ≤1/>128 (79) 4/>64 (67) 4/>32 (79) 1/>8 (58) ≤0.5/>8 (83) 1/>8 (71) ≤2/8 (83) ≤1/128 (79) ≤1/>32 (75) ≤0.5/>4 (75) ↵ a ETP, ertapenem; IPM, imipenem; P/T, piperacillin-tazobactam; A/C, amoxicillin-clavulanic acid; CFL, cephalexin; CAZ, ceftazidime; CIP, ciprofloxacin; LVX, levofloxacin; MXF, moxifloxacin; GM, gentamicin; AMK, amikacin; DOX, doxycycline; T/S, trimethoprim-sulfamethoxazole.
↵ b Escherichia coli (n = 20), Enterobacter cloacae (n = 21), Enterobacter aerogenes (n = 7), Enterobacter gergoviae (n = 1), Enterobacter intermedius (n = 1), Citrobacter freundii (n = 1), Citrobacter koseri (n = 4), Klebsiella oxytoca (n = 16), Klebsiella pneumoniae (n = 9), Pantoeae agglomerans (n = 3), and Serratia marcescens (n = 15).
↵ c Proteus mirabilis (n = 26), Proteus vulgaris (n = 4), Providencia rettgeri (n = 6), Providencia rustigianii (n = 1), Providencia stuartii (n = 1), and Morganella morganii (n = 17).
↵ d NI, no interpretation.
↵ e Alcaligenes faecalis (n = 10), Acinetobacter baumannii (n = 6), Acinetbacter calcoaceticus (n = 1), Brevundimonas diminuta (n = 1), Chryseobacterium sp. (n = 1), Myroides odoratum (n = 1), Paracoccus sp. (n = 1), Pseudomonas fluorescens (n = 2), and Shewanella putrefaciens (n = 1).
- TABLE 6.
In vitro activities of antimicrobial agents against anaerobic organisms
Organism (no. of isolates) MIC50/MIC90 (μg/ml [% susceptible])a ETP P/T A/C CM LVX MXF Bacteroides fragilis groupb (51) 0.5/4 (100) 2/8 (100) 0.5/8 (80) 1/>32 (67) 8/>16 (33) 2/>16 (57) Fusobacterium spp.c (10) ≤.015/0.25 (100) ≤0.06/2 (100) ≤0.06/0.5 (100) ≤0.06/2 (90) 0.5/4 (80) 0.25/2 (90) Porphyromonas spp.d (53) ≤0.015/≤0.015 (100) ≤0.06/≤0.06 (100) ≤0.06/0.125 (100) ≤0.06/>32 (87) 0.5/2 (91) 0.5/1 (98) Prevotella spp.e (66) 0.125/0.25 (100) ≤0.06/≤0.06 (100) ≤0.25/2 (100) ≤0.06/>32 (77) 2/>16 (45) 2/>16 (64) Clostridium spp.f (20) 0.03/1 (100) 0.125/4 (100) ≤0.06/0.5 (100) 1/8 (80) 0.25/16 (80) 0.5/8 (80) Finegoldia magna (110) 0.06/0.125 (100) ≤0.06/0.125 (100) 0.125/0.25 (100) 0.5/8 (81) 8/>16 (40) 2/16 (64) Peptoniphilus asaccharolyticus (40) ≤0.015/0.125 (100) ≤0.06/0.125 (100) ≤0.06/0.25 (100) 0.25/>32 (78) 4/>16 (35) 0.5/16 (78) Miscellaneous gram-positive coccig (77) 0.06/0.25 (100) ≤0.06/0.5 (100) ≤0.06/0.25 (100) 0.125/4 (90) 4/>16 (62) 1/16 (82) Miscellaneous gram-positive rodsh (49) 0.06/0.5 (100) ≤0.06/4 (96) ≤0.06/0.5 (100) ≤0.06/>32 (84) 0.5/8 (80) 0.5/4 (88) ↵ a ETP, ertapenem; P/T, piperacillin-tazobactam; A/C, amoxicillin-clavulanic acid; CM, clindamycin; LVX, levofloxacin; MXF, moxifloxacin.
↵ b Bacteroides caccae (n = 2), B. distasonis (n = 1), B. fragilis (n = 19), B. ovatus (n = 7), B. stercoris (n = 4), B. thetaiotaomicron (n = 8), B. uniformis (n = 5), and B. vulgatus (n = 5).
↵ c Fusobacterium nucleatum (n = 7) and Fusobacterium varium (n = 3).
↵ d Porphyromonas asaccharolytica (n = 30), P. somerae (n = 21), P. catoniae (n = 1), and P. endodontalis (n = 1).
↵ e Prevotella bivia (n = 29), P. corporis (n = 6), P. disiens (n = 5), P. enoeca (n = 1), P. intermedia (n = 3), P. melaninogenica (n = 11), P. oralis (n = 1) P. oris (n = 2), P. pallens (n = 1), P. tannerae (n = 2), P. veroralis (n = 1), and Prevotella spp. (n = 4).
↵ f Clostridium aminovalericum (n = 1), C. cadaveris (n = 4), C. clostridioforme (n = 3), C. innocuum (n = 1), C. malenominatum (n = 1), C. perfringens (n = 6), C. septicum (n = 1), C. sphenoides (n = 1), and C. subterminale (n = 2).
↵ g Peptostreptococcus anaerobius (n = 15), Peptostreptococcus micros (n = 7), Peptoniphilus harei (n = 4), Peptoniphilus indolicus (n = 1), Peptoniphilus ivorii (n = 1), Peptoniphilus lacrimalis (n = 1), Anaerococcus prevotii (n = 14), Anaerococcus octavius (n = 1), Anaerococcus tetradius (n = 9), Anaerococcus vaginalis (n = 7), Gemella morbillorum (n = 3), Ruminococcus productus (n = 1), and anaerobic gram-positive cocci (n = 13).
↵ h Eubacterium lentum (n = 1), Eubacterium limosum (n = 1), Eubacterium nodatum (n = 1), Eubacterium saburreum (n = 1), Eubacterium spp. (n = 13), Propionibacterium acnes (n = 19) Propionibacterium sp. (n = 1), Actinomyces meyeri (n = 1), Actinomyces odontolyticus (n = 1), Actinomyces turicensis (n = 1), Arcanobacterium pyogenes (n = 1), Corynebacterium CDC group G-like (anaerobic) (n = 2), Lactobacillus brevis (n = 1), Lactobacillus casei (n = 1), Lactobacillus plantarum (n = 2), Lactobacillus uli (n = 1), and an unusual gram-positive bacillus (n = 1).
