Necrotizing Fasciitis Caused by Hypermucoviscous Klebsiella pneumoniae in a Filipino Female in North America

Daniel Ng, MD; Brad Frazee, MD


Western J Emerg Med. 2015;16(1):165-168. 

In This Article

Abstract and Introduction


Necrotizing fasciitis caused by Klebsiella pneumoniae has been described in Southeast Asia, but has only recently begun to emerge in North America. The hypermucoviscous strain of K. pneumoniae is a particularly virulent strain known to cause devastatingly invasive infections, including necrotizing fasciitis. Here we present the first known case of necrotizing fasciitis caused by hypermucoviscous K. pneumoniae in North America.


Klebsiella pneumoniae is a member of the enterobacteriacea family of gram-negative rods that are found primarily in the human gastrointestinal tract. The most common forms of Klebsiella infection are hospital- acquired urinary tract infections, pneumonia, and bacteremia. Much of the recent literature surrounding K. pneumoniae has been in regards to its role as a carrier of extended spectrum beta-lactamase (ESBL), and more recently, as the predominant carbapenem resistant enterobacteriaceae (CRE) species. CRE is a new class of multi-drug resistant species that tend to infect elderly patients after prolonged hospital stays or in long-term care facilities.[1] The substantial mortality associated with CRE infections is likely due the lack of effective treatments and underlying vulnerability of the patients, rather than virulence of the bacteria.[1]

This case report describes a strain of K. pneumoniae, referred to as hypermucoviscous, that is distinctly different from CRE. Hypermucoviscous K. pneumoniae, unlike CRE, is community acquired, highly virulent and essentially pansensitive.[2] Hypermucoviscous K. pneumoniae causes invasive infections, including liver abscess, endopthalmitis, meningitis, empyema, and necrotizing fasciitis, that occur primarily in Southeast Asia. Here we report a case of monomicrobial necrotizing fasciitis caused by hypermucoviscous K. pneumoniae in a Filipino woman who presented to our public hospital in Oakland, California. While there have been limited reports of infection with this unusual K. pneumoniae strain outside of Asia, to our knowledge this is the first report of necrotizing fasciitis caused by confirmed hypermucoviscous K. pneumoniae in North America.