First report of NDM-1-producing Klebsiella pneumoniae imported from Africa to Italy: Evidence of the need for continuous surveillance.

Objectives: NDM-producing Enterobacteriaceae are considered emergent on the African continent and have been increasingly reported in recent years. In contrast, strains producing NDM-type enzymes have been rarely reported in Italy, usually associated with sporadic cases or small outbreaks. Here we report two cases of infection caused by NDM-1-producing Klebsiella pneumoniae (NDM-KP) in two unrelated patients returned from travel to Egypt.

Case Reports: The two patients had been previously hospitalised for a short period in two different Egyptian hospitals. In our institution in Italy, NDM-KP isolates were detected from surgical wound drainage (patient #1) and respiratory secretions and blood cultures (patient #2). Rectal swabs of both patients were persistently positive for NDM-KP. In both cases, NDM-1-producing isolates exhibited a multidrug-resistant phenotype, being susceptible only to tigecycline and colistin. Analysis by multilocus sequence typing (MLST) revealed that the two K. pneumoniae isolates were not clonally related, belonging to different sequence types (STs), namely ST15 from patient #1 and ST11 from patient #2.

Conclusions: To the best of our knowledge, this is the first report of NDM-producing isolates imported from Africa to Italy, with no obvious link to the Indian subcontinent. Our experience confirms that Egypt is an emergent source of NDM-producing Enterobacteriaceae, thus representing a cause of concern for Mediterranean countries. Owing to its geographical position, Italy is a first-line European checkpoint with respect to African countries and plays a pivotal role in limiting the dissemination of high-risk clones, especially considering the latest strong migration flows.