[Antibiotic resistance of bacterial strains isolated from bacteremias in immuno-compromised patients]

Immunocompromised hosts are subjects of predilection to bloodstream infections. The global mortality is high. Bacterial strains are frequently multiresistant; fungemias are almost always deadly, in spite of the susceptibility of the fungus.

to evaluate the positive blood cultures in patients with malignant and non-malignant diseases and to determine the resistance mechanisms with the Vitek2.

a 29 months study--181 episodes of invasive infections--168 patients. The blood culture vials were Bactec Plus. The isolates were identified using Api galleries and with the Vitek 2. The susceptibility was tested by the disk-diffusion method (Oxoid Ltd.). Minimal inhibitory concentrations: Vitek2.

EUCAST 2008 standard.

overall mortality: 27%. Gram-negative bacilli: 59.4% and 48.5% Gram-positive cocci. Klebsiella pneumoniae and Escherichia coli isolates accounted for 16.43% and 71.23%respectively; 25% of E. coli strains and 33% of K. pneumoniae respectively, produced extended-spectrum beta-lactamases. Oxacillin resistance: 54.4% of S. aureus isolates. No resistance to carbapenems in enterobacteria.

Bacterial resistance is not likely to decrease, if at all; Death produced by infections is an event that can be prevented. Molecular determinations should be performed to assess the role of the virulence genes and of the resistance mechanisms and to help the better understanding of the interractions between bacteria and the human organism.