Emedinews : New Delhi metallo-beta-lactamase (NDM-1)

Enterobacteriaceae isolates carrying a novel MBL gene, the New Delhi metallo-beta-lactamase (NDM-1) was first described in December 2009 in India with Klebsiella pneumoniae (1). Later, it was described in patients who had traveled to and undergone procedures in India and Pakistan (2). Cases were also reported in Asia, Europe, and North America (2-4). Isolates have also included E. coli and Enterobacter cloacae (2).

Risk factors

1. Recent treatment with carbapenem

2. Indwelling urinary or venous catheters

3. Severe illness (5)

4. NDM-1 can inactivate all beta-lactams except aztreonam.

Salient points

1. It is an important emerging resistant pathogen (6).

2. NDM1 isolates are susceptible to colistin or tigecycline

3. The susceptibility is short-lived.

4. NDM-1 has been identified in public water supplies in India (7)

References

1. Yong D, Toleman MA, Giske CG, et al. Characterization of a new metallo-beta-lactamase gene, bla(NDM-1), and a novel erythromycin esterase gene carried on a unique genetic structure in Klebsiella pneumoniae sequence type 14 from India. Antimicrob Agents Chemother 2009;53:5046.

2. Kumarasamy KK, Toleman MA, Walsh TR, et al. Emergence of a new antibiotic resistance mechanism in India, Pakistan, and the UK: a molecular, biological, and epidemiological study. Lancet Infect Dis 2010;10:597.

3. Centers for Disease Control and Prevention (CDC). Detection of Enterobacteriaceae isolates carrying metallo-beta-lactamase - United States, 2010. MMWR Morb Mortal Wkly Rep 2010;59:750.

4. Sidjabat H, Nimmo GR, Walsh TR, et al. Carbapenem resistance in Klebsiella pneumoniae due to the New Delhi Metallo-β-lactamase. Clin Infect Dis 2011;52:481.

5. Deshpande P, Shetty A, Kapadia F, et al. New Delhi metallo 1: have carbapenems met their doom? Clin Infect Dis 2010;51:1222.

6. Nordmann P, Poirel L, Toleman MA, Walsh TR. Does broad-spectrum {beta}-lactam resistance due to NDM-1 herald the end of the antibiotic era for treatment of infections caused by Gram-negative bacteria? J Antimicrob Chemother 2011;66:689.

7. Walsh TR, Weeks J, Livermore DM, Toleman MA. Dissemination of NDM-1 positive bacteria in the New Delhi environment and its implications for human health: an environmental point prevalence study. Lancet Infect Dis 2011;11:355.