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Introduction: Bordetella hinzii has been isolated mainly from respiratory specimens and from blood of immunocompromised patients, and Bordetella trematum from ear infections or leg, arm and ankle wounds and from diabetic foot ulcers. Bordetella holmesii is instead associated with bactaeremia in young adults, mostly with underlying conditions. Only three septic arthritis cases due to this species have been described in the literature. Case presentation: Herein we describe four cases of infections due to Bordetella species that have been recovered from unusual infection sites: two cases of B. hinzii infections, one recovered from the urine of a patient with chronic prostatitis and the other from a liver cyst in an immunocompetent patient; one B. trematum case from a bone biopsy of a patient with chronic osteomyelitis of the hip; and one B. holmesii case isolated from the joint fluid of an immunocompetent patient with diagnosed septic arthritis. The organisms were identified using standard biochemical tests, by API 20 NE version 6.0, by automated system VITEK 2, by mass spectrometry using the Bruker Daltonics MicroFlex LT spectrometer with MALDI Biotyper 3.1, and by PCR amplification of 16S rRNA. Antibiotic susceptibility testing was performed using the VITEK 2 system, except for B. holmesii, for which the epsilometric method (Etest technique; bioMérieux) was used. Conclusion: We highlight the importance of isolating Bordetella species from severe infections and unusual sites, and also of combining both phenotypic and genotypic methods for definitive identification.

Identifying the risk factors for carbapenem-resistant Enterobacterales (CRE) bacteremia in cancer and hematopoietic stem cell transplantation (HSCT) patients would allow earlier initiation of an appropriate empirical antibiotic treatment. This is a prospective multicenter observational study in patients from 12 centers in Argentina, who presented with cancer or hematopoietic stem-cell transplant and developed Enterobacterales bacteremia. A multiple logistic regression model identified risk factors for CRE bacteremia, and a score was developed according to the regression coefficient. This was validated by the bootstrap resampling technique. Four hundred and forty-three patients with Enterobacterales bacteremia were included: 59 with CRE and 384 with carbapenem-susceptible Enterobacterales (CSE). The risk factors that were identified and the points assigned to each of them were: ≥10 days of hospitalization until bacteremia: OR 4.03, 95% CI 1.88–8.66 (2 points); previous antibiotics > 7 days: OR 4.65, 95% CI 2.29–9.46 (2 points); current colonization with KPC-carbapenemase-producing Enterobacterales: 33.08, 95% CI 11.74–93.25 (5 points). With a cut-off of 7 points, a sensitivity of 35.59%, specificity of 98.43%, PPV of 77.7%, and NPV of 90.9% were obtained. The overall performance of the score was satisfactory (AUROC of 0.85, 95% CI 0.80–0.91). Finally, the post-test probability of CRE occurrence in patients with none of the risk factors was 1.9%, which would virtually rule out the presence of CRE bacteremia.

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Cronobacter species are opportunistic pathogens associated with severe infections in neonates and immunocompromised infants. From January 2009 through September 2010, two cases of neonatal infections associated with Cronobacter malonaticus and one case associated with Cronobacter sakazakii, two of them fatal, were reported in the same hospital. These are the first clinical isolates of Cronobacter spp. in Argentina. The objective of this work was to characterize and subtype clinical isolates of Cronobacter spp. in neonate patients, as well as to establish the genetic relationship between these isolates and the foodborne isolates previously identified in the country. Pulsed-field gel electrophoresis analysis showed a genetic relationship between the C. malonaticus isolates from two patients. Different results were found when the pulsed-field gel electrophoresis patterns of clinical isolates were compared with those deposited in the National Database of Cronobacter spp.