The epidemic clone of Klebsiella pneumoniae ST258 carbapenem resistant cause a persistent infection in a mouse model of peritonitis and subverts the respiratory burst in murine neutrophils

CASTILLO LA; BIRNBERG WEISS F; PITTALUGA JR; MARTIRE-GRECO D; GÓMEZ SA; LANDONI VI; FERNÁNDEZ GC

Congreso; LXVIII Reunión Anual de la Sociedad Argentina de Inmunología 2019; 2020

Klebsiella pneumoniae (Kp), an opportunistic pathogen, usually affects immunosuppressed patients, and the increase of their resistance to antimicrobials is associated with high mortality. Our previous results showed that Kp sequence type 258, Kp carbapenemase(KPC) producer (Kp258KPC+), is able to impair the respiratory burstand release of NETs by human neutrophils (PMN). Now, a murinemodel of peritonitis was used, in order to evaluate if the subversion of PMN microbicidal functions represents a real advantage forthe bacteria. In a lethality test, the highest dose of Kp258KPC+ injected (108UFC, i.p), did not cause any death 24h post-infection,while 107UFC of Escherichia coli (Eco), used as control, was lethalin 71% of infected mice. Kp258KPC+ induced an important recruitmentof leukocytes to the peritoneum within 24h, compared to Eco (Leukocytes/L: Kp258KPC+= 3.5x109 ± 0.6; Eco: 2.1x109 ± 0.4; p