Four Infants with Upper Urinary Tract Infection due to Extended-spectrum β lactamase (ESBL)-producing Escherichia coli

Bacteriuria With CTX-M-8 Extended-Spectrum β-Lactamase-Producing Escherichia coli in a Patient With Incomplete Kawasaki Disease

We report the case of a 2-month-old infant with incomplete Kawasaki disease that presented as an apparent urinary tract infection. The patient's fever persisted despite antibiotic treatment. Intravenous immunoglobulin and aspirin therapy cured both the incomplete Kawasaki disease and bacterial pyuria. Renal sonography, voiding cystourethrography, and renal parenchyma radionuclide scanning did not detect any abnormalities. Temporary dilation of the coronary artery was noted. In a urine specimen obtained through transurethral catheterization, the growth of 10⁵ colony-forming units/mL of extended-spectrum β-lactamase-producing Escherichia coli was detected. Polymerase chain reaction analysis revealed that the enzyme genotype was CTX-M-8, which is a rare type in Japan. In conclusion, attention should be paid to a misleading initial presentation of fever and pyuria, which might be interpreted as urinary tract infection in patients with Kawasaki disease. Furthermore, pediatricians should consider incomplete Kawasaki disease when patients present with fever and pyuria, which are consistent with urinary tract infection, but do not respond to antibiotic treatment.

Community spread of extended-spectrum β-lactamase-producing bacteria detected in social insurance hospitals throughout Japan

We surveyed the status of community-acquired infections involving four extended-spectrum β-lactamase (ESBL)-producing bacteria (Escherichia coli, Klebsiella pneumoniae, Klebsiella oxytoca, Proteus mirabilis) isolated from clinical specimens from 11 social insurance hospitals in Japan in 2012. These are member hospitals of the Japan Community Healthcare Organization, an independent administrative hospital organization. The isolation rates for E. coli, K. pneumoniae, K. oxytoca, and P. mirabilis were 14.0% (165/1176), 3.3% (16/480), 3.1% (4/130), and 15.9% (17/107), respectively. The CTX-M-9 group, the most frequently detected genotype, was found in 77.0% (127/165) of E. coli and 43.8% (7/16) of K. pneumoniae isolates. Among K. oxytoca isolates, 75% (3/4) were the CTX-M-1 group, and all 17 P. mirabilis strains were the CTX-M-2 group. ESBL-producing bacteria isolation rates in each hospital ranged from 5.8% to 21.5% (median 9.5%), and the proportion of community-acquired infections among ESBL-producing bacteria isolates ranged from 1.6% to 30.8% (median 11.4%) in each hospital. Overall, the rates of ESBL-producing bacterial infection in all community-acquired infections and in all hospital infections were 10.6% (115/1081) and 10.7% (87/812), respectively. The ESBL-producing bacteria are not limited to certain regions or hospitals but are spreading in communities throughout Japan.

Emergence of extended spectrum-β-lactamase-producing Escherichia coli O25b-ST131: a major community-acquired uropathogen in infants

BACKGROUND

Escherichia coli sero-group O25b-sequence type 131 (O25b-ST131), a multidrug-resistant clonal group, is a significant pathogen in adults and children. This study investigated the genotyping and role of extended spectrum β-lactamase (ESBL)-producing E. coli O25b-ST131 and non-O25b-ST131 in urinary tract infections in infants.

METHODS

Clinical and laboratory data from 111 infants less than 1 year of age, who were hospitalized for urinary tract infections caused by ESBL-producing E. coli between 2009 and 2012 were collected. Polymerase chain reactions and multi-locus sequence typing were used to identify E. coli O25-ST131 clones. The gene blaCTX-M groups 1, 2 and 9, a specific polymerase chain reaction of CTX-M 14 and 15, were also determined in ESBL-producing E. coli isolates.

RESULTS

O25b-ST131 accounted for 65% of the 111 isolates, although 92 isolates belonged to the blaCTX-M group 9, of which most were CTX-M-14. Those with O25b-ST131 clones had similar risk factors, clinical features and outcomes as those with non-O25b-ST131. The E. coli O25b-ST131 isolates were more resistant to ciprofloxacin and gentamicin, but more susceptible to cefoxitin, minocycline and trimethoprim/sulfamethoxazole than the non-O25b-ST131 isolates. Most of the infants (78%) were previously healthy with no apparent risk factors.

CONCLUSIONS

E. coli O25b-ST131 is a major community-acquired uropathogen in the infant population. Regardless of O25b-ST131 or non-O25b-ST131 clones, CTX-M-14 accounts for majority of the ESBL genotype. The O25b-ST131 clone is not associated with more severe clinical disease, but it may make the diagnosis and selection of antimicrobials for treatment more challenging.