Native bone and joint infections caused by extended-spectrum β-lactamase-producing Enterobacterales: experience of a reference centre in the Greater Paris area

Recurrent joint infection caused by a multidrug-resistant capnophilic Escherichia coli ST131 O25H4 strain

We report a case of a native knee septic arthritis and subsequent osteomyelitis due to a CO2-dependent (capnophilic) multidrug-resistant E. coli ST131 O25:H4 strain. Capnophilic phenotype made microbiology investigation challenging; susceptibility testing could not be performed and the organism did not grow in the urine culture using standard method. The combination of unique virotype and capnophilia may have contributed to the aggressiveness of this organism and the initial unsuccessful carbapenem course, leading to recurrent infection.

Hip joint infections caused by multidrug-resistant Enterobacterales among patients with spinal cord injury: experience of a reference center in the Greater Paris area

Introduction

We aimed to describe the management and treatment of hip joint infections caused by multidrug-resistant Enterobacterales among patients with spinal cord injury (SCI).

Methods

We included all hip joint infections associated with grade IV decubitus ulcers caused by Extended-Spectrum Beta-Lactamase producing Enterobacterales (ESBL-PE) and Carbapenemase-Producing Enterobacterales (CPE) treated in a reference center for bone and joint infections (BJIs) over 9 years in a retrospective study.

Results

Seventeen SCI patients with ischial pressure ulcers breaching the hip capsule (mean age 52 ± 15 years) were analyzed. In 16 patients, paraplegia was secondary to trauma and one was secondary to multiple sclerosis. Infections were mostly polymicrobial (n=15; 88.2%), notably caused by Klebsiella pneumoniae (n=10) and S. aureus (n=10). The carbapenemases identified were exclusively OXA-48-type (n=3) including 2 isolates co-expressed with ESBL-PE within the same bacterial host.

Multidrug-resistant Enterobacterales were commonly resistant to fluoroquinolones (n=12; 70.6%). Most therapies were based on carbapenems (n=10) and combination therapies (n=13). Median duration of treatment was 45 (6-60) days. Of 17 cases of hip joint infections, 94.1% (n=16) benefited from a femoral head and neck resection.

Infection control was initially achieved in 58.8% (n=10) of cases and up to 88.2% after revision surgeries, after a median follow-up of 3 (1-36) months.

Conclusion

Hip infections among SCI patients caused by multidrug-resistant Enterobacterales are often polymicrobial and fluoroquinolones-resistant infections caused by K. pneumoniae and S. aureus, highlighting the need for expert centers with pluridisciplinary meetings associating experienced surgeons, clinical microbiologists and infectious disease specialists.