Table 3

Distribution of antimicrobial drug resistance in relation to source group and ST131 status among 953 E. coli isolates from reproductive-age women with cystitis or pyelonephritis and from healthy fecal controls

Antibiotic resistance or other traitaNo. (column %) with trait by isolate source and ST131 statusP values by isolate source (vs ST131)b
FecalCystitisPyelonephritis
ST131 (n = 4)Non-ST131 (n = 326)ST131 (n = 42)Non-ST131 (n = 280)ST131 (n = 89)Non-ST131 (n = 212)FecalCystitisPyelonephritis
Antibiotics
    Ampicillin4 (100)78 (24)42 (100)93 (33)89 (100)71 (33)0.004<0.001<0.001
    Amoxicillin-clavulanate4 (100)42 (13)42 (100)48 (17)89 (100)13 (6)<0.001<0.001<0.001
    Cephalothin1 (25)46 (14)23 (55)106 (38)54 (61)103 (49)NS0.043NS
    TMP-SMZ2 (50)23 (7)22 (52)42 (15)52 (58)35 (17)NS<0.001<0.001
    Nitrofurantoin0 (0)3 (1)4 (10)6 (2)9 (10)0 (0)NS0.029<0.001
    Gentamicin1 (25)3 (1)9 (21)10 (4)13 (15)8 (4)0.039<0.0010.002
    Amikacin0 (0)0 (0)3 (6)3 (1)5 (6)1 (<1)NS0.0310.010
    Norfloxacin1 (25)13 (4)15 (36)25 (9)37 (42)5 (2)NS<0.001<0.001
    Ciprofloxacin1 (25)13 (4)15 (35)26 (9)36 (41)5 (2)NS<0.001<0.001
    Imipenem0 (0)0 (0)1 (2)1 (<1)1 (1)1 (<1)NS
    Nalidixic acid1 (25)16 (5)24 (58)44 (16)58 (65)14 (6)NS<0.001<0.001
    Tetracycline4 (100)104 (32)37 (88)166 (59)84 (94)112 (53)0.011<0.001<0.001
    Ceftriaxone0 (0)3 (1)4 (10)9 (3)11 (12)7 (3)NSNS0.006
    Ceftazidime0 (0)0 (0)1 (2)2 (1)3 (3)9 (4)NSNSNS
ESBL production0(0)3 (1)5 (11)9 (3)17 (19)10 (5)NS0.002<0.001
Resistance to >1 agent4 (100)75 (23)42 (100)93 (33)89 (100)71 (33)NS<0.001<0.001
Biofilm production4 (100)52 (16)36 (86)151 (53)89 (100)128 (60)NS<0.001<0.001
Resistance score (median [range])5 (5–9)2 (0–8)7 (5–11)5 (0–9)9 (7–13)8 (3–10)<0.001<0.001<0.001
  • a TMP-SMZ, trimethoprim-sulfamethoxazole; ESBL, extended-spectrum β-lactamase.

  • b P values are shown where P < 0.05, as calculated by Fisher's exact test; in the last row, the Mann-Whitney U test was used. P values for ST131 by source group of fecal versus pyelonephritis and cystitis versus pyelonephritis were nonsignificant. NS, nonsignificant.