Characteristics and Clinical Implications of Carbapenemase-Producing Klebsiella pneumoniae Colonization and Infection, Italy.

carbapenemase–producing (KPC) has been endemic in Italy since 2013. In a multicenter cohort study, we investigated various aspects of KPC among patients, including 15-day mortality rates and delays in adequate therapy. Most (77%) KPC strains were sequence type (ST) ST512 or ST307. During 2017, KPC- prevalence was 3.26 cases/1,000 hospitalized patients. Cumulative incidence of KPC- acquired >48 hours after hospital admission was 0.68% but varied widely between centers. Among patients with mild infections and noninfected colonized patients, 15-day mortality rates were comparable, but rates were much higher among patients with severe infections. Delays of 4 days in receiving adequate therapy more frequently occurred among patients with mild infections than those with severe infections, and delays were less common for patients with known previous KPC colonization. Italy urgently needs a concerted surveillance system to control the spread of KPC-.