[Risk factors and clinical evolution of carbapenemase-producing Klebsiella pneumoniae infections in a university hospital in Spain. Case-control study].

OBJECTIVE: Carbapenemase-producing Enterobacterias is a global health hazard due to their ease of transmission, difficulty of treatment, and their personal and economic impact. We analyze the factors associated with an increased risk of infection by Klebsiella pneumoniae carbapenemase-producing bacteria (KPC) and factors related to poor prognosis.

METHODS: We designed a case-control study. KPC isolates were taken during an outbreak in a hospital in Madrid. A logistic regression was performed with the main variables.

RESULTS: Sixteen cases of clinically documented infections were isolated. Overall mortality rates in the cases group was 25%. The most frequent location was blood (37.5%) followed by urine (25%). All but one were OXA-48. Regarding factors related to an increased risk of developing infection, only previous exposure to antibiotics presented statistical significance difference OR 13 (2.40-70.46). With respect to the overall mortality, the presence of pneumonia OR 25 (1.93-323.55) or the use of invasive mechanical ventilation was associated with greater risk 15 OR 33 (1.92-122.8) For attributable mortality only invasive ventilation had a significant association OR 18 (1.48-218.95).

CONCLUSIONS: Exposure to previous antibiotics is an independent risk factor for developing KPC infection, adjusted for all other clinical and demographic variables. Risk factors such as the presence of pneumonia or the use of invasive mechanical ventilation were associated with a worse prognosis in terms of overall and attributable mortality.