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Pyogenic liver abscess caused by an atypical hypervirulent Klebsiella pneumoniae K1-ST23 in Mexico
Lucía Martínez-Hernandez1, Alejandro Alvarado-Delgado2, Nadia Rodríguez-Medina2
1Departamento de Infectología y Microbiología Clínica del Hospital Español, Ciudad de México, Mexico.
Abstract:
Hypervirulent K. pneumoniae infection has been raising worldwide and is one of the major causes of community-acquired pyogenic liver abscess. We described a case report of pyogenic liver abscess caused by an atypical hypervirulent (non-hypermucoviscous) K. pneumoniae K1 ST23 in a diabetic Asian patient who resided in Mexico. The susceptibility to antimicrobials, pathogenicity, molecular and genomic analysis were determined. A man from Guangdong (China) with a recent diagnosis of diabetes mellitus was admitted to the hospital, and he denied traveling in the last 3 months. A computed tomography revealed a right lobe liver abscess. On the third day after admission a Klebsiella pneumoniae isolate (14652) was obtained. The isolate corresponded to a susceptible K. pneumoniae with capsular type K1 and ST23 (CG23) and exhibited a non-hypermucoviscous phenotype. The isolate 14652 was genetically related to the globally distributed lineage ST23-KL1. This study describes the first case in Mexico of K. pneumoniae capsular type K1 and ST23 with an atypical hypervirulent phenotype.
Insights
A rare, atypical hypervirulent Klebsiella pneumoniae (K. pneumoniae) strain caused a liver abscess in a diabetic patient in Mexico. This K1 ST23 strain was non-hypermucoviscous, highlighting evolving virulence factors in K. pneumoniae infections.
Area of Science:
- Infectious Diseases
- Microbiology
- Genomics
Background:
- Hypervirulent Klebsiella pneumoniae (K. pneumoniae) infections are a growing global concern, frequently causing community-acquired pyogenic liver abscesses.
- Traditional hypervirulent K. pneumoniae strains are often characterized by a hypermucoviscous phenotype.
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