The Rapid Induction of Carbapenem-Resistance in an <i>Aeromonas dhakensis</i> Blood Isolate

Abstract

SUMMARY: Meropenem-susceptible and -resistant Aeromonas dhakensis isolates from blood cultures of a fatal case of septicemia were analyzed. The two isolates were homologous and gene expression of metallo-b-lactamase in the resistant strain was upregulated. Physicians should be aware of the possibility of the induction of carbapenem-resistance, following the use of carbapenems in the treatment of Aeromonas infection.In an earlier study, conducted at a hospital in Japan, we observed that Aeromonas septicemia occurred frequently in hospitalized patients with underlying diseases, including malignancy (1). In this report, a fatal case of Aeromonas septicemia in a girl with neutropenia is described. Two strains of Aeromonas veronii biovar sobria were isolated from blood cultures obtained before and after treatment with carbapenem. The strain isolated at the onset of sepsis was sensitive to carbapenem; however, the strain isolated after treatment, was resistant. Aeromonas species have chromosomal genes, such as cphA and imiS, encoding metallo-b-carbapenemase, which are not commonly expressed, but inducible. These genes have similar sequences and the enzymes can hydrolyze carbapenems efficiently (2,3). To understand the mechanism underlying the development of resistance to carbapenem, we analyzed the genetic homology between the blood isolates and the gene expression levels of the chromosomal metallo-blactamase.The two Aeromonas strains (meropenem-susceptible, MIC 0.5 mg/mL; meropenem-resistant, MIC

Clinical characteristics and risk factors of Aeromonas bloodstream infections in patients with hematological diseases

“…In this study, the susceptible rate of Aeromonas to aminoglycosides and quinolones was > 90%, which is similar to the results of other research results [ 10 , 33 ]. In conformance to other studies, it is worth noting that resistance induction was also found during the treatment period in five cases [ 30 , 34 ]. Four patients developed quinolones resistance.…”

“…Carbapenem antibiotics are one of the most important empiric therapy for patients with hematological diseases as they exhibit a broad spectrum activity against gram-negative bacilli [ 29 ]. Unfortunately, after using carbapenems for a short time, carbapenem resistance emerges, including Aeromonas [ 30 ]. However, Aeromonas can exhibit rare phenotypes such as carbapenem resistance and cephalosporin susceptible.…”

Pulmonary infection with Aeromonas dhakensis in a patient with acute T lymphoblastic leukemia: a case report and review of the literature

“…According to the previously reported cases (Table 2), most were out-of-hospital infections, the disease progressed rapidly, the 14-day mortality rate was high, and the cause of death was mostly bacteremia or systemic infection. These reported cases were all misjudged in the early diagnostic process based on routine biochemical tests and were eventually confirmed by etiological sequencing (6,14,16,18). Pulmonary infection caused by Aeromonas dhakensis has rarely been reported.…”

A Case Report and Literature Review of a Death Caused by Aeromonas daca Complicated with Septic Shock

“…However, the production of carbapenem cannot be easily detected in traditional drug sensitivity tests unless a large number of inoculants or additional tests are used. It has been reported that when carbapenem antibiotics were used to treat Aeromonas aeruginosa, A. aeruginosa resistant to carbapenem antibiotics appeared [16]. For severe Candida daca infection, it is suggested that a large number of inoculations and/or additional drug sensitivity tests should be performed prior to carbapenem treatment.…”