Abstract:Objective To evaluate the application value of hypermucoviscous phenotype and virulence gene in predicting hypervirulent Klebsiella pneumoniae (hvKp). Methods Klebsiella pneumoniae isolated from four hospitals in Guangdong Province from November 2016 to April 2018 were collected, mucoviscous phenotypes were determined through string test, virulence genes and serotypes were detected, 50% lethal rate (LD50) of strains was calculated by Galleria mellonella model, LD50 of strains of different hypermucoviscous phenotypes and virulence genes were compared. Results A total of 194 strains of Klebsiella pneumoniae were collected, 40.2% (n=78) of which were positive for string test. Galleria mellonella test results showed that LD50 of only iucA, iroB, and fimH positive strains was lower than that of corresponding negative strains(P < 0.05). LD50 of strain group of all positive for iucA+iroB+fimH+hm (n=58), iucA positive+iroB positive+fimH positive+hm negative (n=23) and all negative for iucA+iroB+fimH+hm (n=28) were (5.39±0.71), (5.44±0.62), and (5.83±0.64) lg10CFU/mL respectively, there was no significant difference between the first two groups (P=0.786), but there was significant difference between the first two groups and the third group (P < 0.05), positive rates of serotypes K1, K2 and K57 in hypermucoviscous phenotype strains were significantly higher than those in non-hypermucoviscous phenotype strains, difference were all significant (all P < 0.001). Conclusion Accuracy of the prediction of hvKp based only on hypermucoviscous phenotype is low, compared with hypermucoviscous phenotype, virulence genes iucA+, iroB+ and fimH + are more accurate to prediction hvKp.