Persistent carriage and infection by multidrug-resistant Escherichia coli ST405 producing NDM-1 carbapenemase: report on the first Italian cases

Abstract

We report on the first detection of the NDM-1 carbapenemase in Italy, in Escherichia coli isolated in October 2009. Prolonged colonization and relapsing infection by NDM-1-positive E. coli were observed in a patient (index case) with an indirect epidemiological link with areas of endemicity. Transient colonization was apparently observed in another patient linked with the index case.

Fig. 1.

(a) Diagram showing the times of isolation of NDM-1-positive E. coli (NDM-EC) from patients 1 and 2 and attendance at the BMTU (thick lines), other hospital wards (thin lines), and the day hospital clinic (dashed lines) by patients 1, 2, and 3. The lack of detection of NDM-1-positive isolates from fecal swabs is also indicated, as is the reported intestinal colonization by carbapenem-resistant E. coli (NEM-R EC), for which NDM-1-production could not be documented. (b) PFGE profiles of the bla_NDM-1-positive E. coli isolates following digestion with XbaI. Molecular size standards are indicated, in kb, on the left.