Recent trend of necrotizing fasciitis in Taiwan: focus on monomicrobial Klebsiella pneumoniae necrotizing fasciitis.
BACKGROUND
Necrotizing fasciitis (NF) is a rapidly progressive, life-threatening soft-tissue infection that is traditionally caused by group A Streptococcus (GAS) or mixed aerobic/anaerobic bacteria. Monomicrobial Klebsiella pneumoniae NF (KP-NF) has been reported since 1996 but has not yet been systematically studied.


METHODS
We retrospectively studied consecutive NF cases treated at a university hospital in Taiwan during 1997-2010 and investigated the clinical characteristics and outcomes associated with monomicrobial KP-NF, using monomicrobial GAS-NF as a reference. We also analyzed the virulence gene profiles of the isolated K. pneumoniae strains.


RESULTS
Of 134 NF cases, 88 were monomicrobial, of which the most common pathogens were GAS (n = 16) and K. pneumoniae (n = 15). Monomicrobial KP-NF entailed a moderate risk of limb loss (20% vs 25%; P = 1.000) and high mortality (47% vs 19%; P = .135), and it was more likely to involve bacteremia (80% vs 31%; P = .011), concomitant distant abscesses (27% vs 0%; P = .043), and underlying immunocompromising conditions (100% vs 63%; P = .018), compared with GAS-NF. The isolated K. pneumoniae strains (n = 10) were of capsular polysaccharides genotype K1 (n = 4), K54/K20/K5 (n = 4), K2 (n = 1), and K16 (n = 1). All strains carried rmpA, iucABCDiutA, and iroA. Genotype K1 strains had a significantly higher risk of concomitant distant abscesses, compared with non-K1 strains (75% vs 0%; P = .033).


CONCLUSIONS
K. pneumoniae has become a common pathogen of monomicrobial NF in Taiwan. Physicians treating patients with monomicrobial KP-NF should be aware of the risk of concomitant distant abscesses, particularly in cases caused by genotype K1.
Department of Surgery, National Taiwan University Hospital, Taipei.
Nai-Chen
NC
Cheng
Yen-Chen
YC
Yu
Hao-Chih
HC
Tai
Po-Ren
PR
Hsueh
Shan-Chwen
SC
Chang
Shau-Yan
SY
Lai
Wen-Ching
WC
Yi
Chi-Tai
CT
Fang
D000328:Adult; D000368:Aged; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D019115:Fasciitis, Necrotizing / Q000453:epidemiology* / Q000382:microbiology* / Q000401:mortality / Q000473:pathology; D005260:Female; D006785:Hospitals, University; D006801:Humans; D007710:Klebsiella Infections / Q000453:epidemiology* / Q000382:microbiology* / Q000401:mortality / Q000473:pathology; D007711:Klebsiella pneumoniae / Q000302:isolation & purification*; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D015995:Prevalence; D012189:Retrospective Studies; D017422:Sequence Analysis, DNA; D013290:Streptococcal Infections / Q000453:epidemiology / Q000382:microbiology / Q000401:mortality / Q000473:pathology; D013297:Streptococcus pyogenes / Q000302:isolation & purification; D016019:Survival Analysis; D013624:Taiwan / Q000453:epidemiology; D016896:Treatment Outcome; D037521:Virulence Factors / Q000235:genetics
D004269:DNA, Bacterial; D037521:Virulence Factors