UTI-triggered Klebsiella split reveals hidden brain-virulence within a patient

A 63-year-old woman with a urinary tract infection developed a brain abscess two years later after a hypervirulent subpopulation of Klebsiella pneumoniae evolved within her urinary tract and disseminated to the brain and eye; genome analysis showed these hypervirulent strains diverged from a common ancestor and arose via capsule-related mutations, illustrating heterovirulence and intra-patient bacterial evolution while remaining antibiotic-susceptible.