Bloodstream infection caused by extensively drug-resistant Acinetobacter baumannii in cancer patients: high mortality associated with delayed treatment rather than with the degree of neutropenia.

This study aimed to describe severe infections with extensively drug-resistant Acinetobacter baumannii-calcoaceticus complex (XDR-ABC), as well as to investigate risk factors for mortality, in cancer patients. It was a retrospective study including all patients diagnosed with XDR-ABC bacteraemia during hospitalization in the intensive care unit of a cancer hospital between July 2009 and July 2013. Surveillance cultures were collected weekly during the study period, and clonality was analysed using pulsed field gel electrophoresis (PFGE). We analysed underlying diseases, oncology therapy, neutrophil counts, infection site and management of infection, in terms of their correlation with 30-day mortality. During the study period, 92 patients with XDR-ABC bacteraemia were identified, of whom 35 (38.0%) were patients with haematological malignancy. We identified XDR-ABC strains with four different profile patterns, 91.3% of patients harbouring the predominant PFGE type. Of the 92 patients with XDR-ABC bacteraemia, 66 (71.7%) had central line-associated bloodstream infections; infection occurred during neutropenia in 22 (23.9%); and 58 (63.0%) died before receiving the appropriate therapy. All patients were treated with polymyxin, which was used in combination therapy in 30 of them (32.4%). The 30-day mortality rate was 83.7%. Multivariate analysis revealed that septic shock at diagnosis of XDR-ABC infection was a risk factor for 30-day mortality; protective factors were receiving appropriate therapy and invasive device removal within the first 48 h. Among cancer patients, ineffective management of such infection increases the risk of death, more so than do features such as neutropenia and infection at the tumour site.

Infection with Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae in solid organ transplantation.

Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae is spreading globally and represents a challenge in infection control and treatment. Solid organ transplant (SOT) recipients are especially at risk for infection by multidrug-resistant bacteria, and little is known about infection with KPC-producing organisms in this setting. The aim of this study was to describe the clinical and microbiologic aspects of KPC-producing K. pneumoniae infections in SOT recipients. A KPC-2-producing K. pneumoniae outbreak was identified in a public teaching tertiary care hospital in São Paulo, Brazil, in June 2009. During the outbreak, cases of KPC-2-producing K. pneumoniae infection in SOT recipients occurred between July 2009 and February 2010; these cases were retrospectively reviewed. Overall, 12 episodes of infection with KPC-producing K. pneumoniae occurred in 2 heart, 4 liver, and 6 kidney transplant recipients with incidence rates of 16.7%, 12.9%, and 26.3% in heart, liver, and kidney transplantation, respectively. Infection occurred at a median time of 20 days after transplantation. Primary infection sites were as follows: 4 urinary tract infections, 4 bloodstream infections, 2 pneumonias, and 2 surgical site infections. All patients except one had received antibiotics in the last 30 days, mostly piperacillin-tazobactam or glycopeptides. All strains exhibited susceptibility to amikacin and gentamicin. Patients were treated with tigecycline plus polymyxin B (3 cases), polymyxin B plus carbapenem (3 cases), polymyxin B alone (3 cases), or tigecycline plus imipenem (1 case). In 2 cases, patients received only carbapenem, and death occurred before the final culture result. The overall 30-day mortality rate was 42%. In this series of KPC-producing K. pneumoniae infection in SOT recipients, the infection occurrence was high during an institutional outbreak and was potentially life threatening.