Treatment Failure Due to Emergence of Resistance to Carbapenem during Therapy for Shewanella algae Bacteremia

Abstract

We describe a case of bacteremia due to imipenem-susceptible Shewanella algae. Despite treatment with imipenem, the patient developed a spinal epidural abscess, from which imipenem-resistant S. algae was isolated. The development of resistance should be monitored when S. algae infection is treated with imipenem, even though the strain is initially susceptible to imipenem. CASE REPORTA 65-year-old man underwent distal pancreatectomy with cholecystectomy because of intraductal papillary mucinous tumor. On hospital day 12 (postoperative day 7), the patient complained of chills and fever. Abdominal sonography showed fluid collection in the abdomen, and percutaneous drainage was performed. Cultures of blood and percutaneous drainage fluid yielded Shewanella algae, which was susceptible to ceftazidime, cefepime, aztreonam, imipenem, and amikacin. It was resistant to piperacillin and gentamicin, as determined by disk diffusion testing. Based on this result, treatment with imipenem (500 mg intravenously [i.v.] every 6 h [q6h]) was instituted. Despite the treatment, the patient remained febrile. On hospital day 25, the patient became agitated and disoriented, and signs of meningismus were evident on his examination. His cerebrospinal fluid (CSF) contained 180 white blood cells/ mm 3 . The CSF protein concentration was 307 mg/dl (reference range, 15 to 45 mg/dl), and the CSF sugar concentration was 41 mg/dl (reference range, 40 to 80 mg/dl). The CSF culture was negative. Imipenem treatment was changed to meropenem treatment. On hospital day 32, he complained of pain in his neck, and weakness of his left arm and left leg developed suddenly. Magnetic resonance imaging (MRI) revealed a spinal epidural abscess extending from the fourth to the sixth cervical vertebrae. The patient underwent hemilaminectomy and discectomy of C4 and C5 with drainage of the epidural abscess, which yielded S. algae on culture.

Relative Frequency, Characteristics, and Antimicrobial Susceptibility Patterns of Vibrio spp., Aeromonas spp., Chromobacterium violaceum, and Shewanella spp. in the Northern Territory of Australia, 2000–2013

“…28 It is notable that the most common carbapenemase present in Aeromonas (CphA) has a very narrow substrate profile that would not affect cefepime, although VIM metallobetalactamases (MBLs) do also occur. 25 Treatment failure caused by the development of carbapenem resistance in Shewanella bacteremia has also been reported 29 ; therefore, carbapenem monotherapy in severe water-associated infections cannot be recommended.…”

Purulent Pericarditis with Greenish Pericardial Effusion Caused by Shewanella algae

“…In our patient, S. algae was initially susceptible to piperacillin-tazobactam and became resistant to piperacillintazobactam 10 days later. Rapid development of drug resistance to imipenem, but not to piperacillin-tazobactam, has been reported (6). The mechanism for the rapid development of drug resistance to piperacillin-tazobactam required further study.…”

In Vitro Synergism of Ciprofloxacin and Cefotaxime against Nalidixic Acid-Resistant Salmonella enterica Serotypes Paratyphi A and Paratyphi B

“…The results were related to the mean value obtained from three independent cultures of 10 8 CFU/ml spread on three different agar plates containing or not containing antibiotics. Along with these assays, all three isolates were also subjected to a serial passage experiment with ciprofloxacin or cefotaxime, as described earlier by Kim et al (14). Briefly, the overnight growth of Salmonella isolates on Mueller-Hinton agar was swabbed onto fresh agar plates containing one-half of the MIC of ciprofloxacin or cefotaxime or on agar plates not containing antibiotics.…”