Increasing Occurrence of Antimicrobial-Resistant Hypervirulent (Hypermucoviscous) Klebsiella pneumoniae Isolates in China

Hypervirulent (hypermucoviscous) Klebsiella pneumoniae strains constitute an increasing proportion of the K. pneumoniae strains isolated from patients in China. Disturbingly, the frequency of antimicrobial-resistant strains identified among these isolates has increased in recent years. Background. New hypervirulent variants of Klebsiella pneumoniae (hvKP) are emerging globally, most of which exhibit antimicrobial susceptibility. Methods. A retrospective study was conducted in 88 patients with cultures positive for K. pneumoniae hospitalized in the Beijing You'an Hospital from April 2010 to June 2012. The clinical and molecular data of the hvKP isolates (defined as string test positive) were compared with those of the classic K. pneumoniae (cKP) isolates. Results. Overall, 33.0% (29/88) of K. pneumoniae isolates were hvKP. Univariate analysis revealed the following risk factors for hvKP: virulence gene rmpA (odds ratio [OR], 16.92 [95% confidence interval {CI}, 4.842–59.145]), capsule antigens K1 (OR, 3.355 [95% CI, 1.153–9.768]) and K2 (OR, 9.280 [95% CI, 0.987–87.250]), alcoholic hepatitis (OR, 7.435 [95% CI, 1.397–39.572]), liver abscess (OR, 9.068 [95% CI, 1.747–47.061]), metastatic infection (OR, 2.752 [95% CI, 1.100–6.886]), community-acquired infection (OR, 10.432 [95% CI, 3.623–30.033]), sputum isolation (OR, 0.312 [95% CI, .095–1.021]), and HIV infection (