Fatal Tension Pneumocephalus Associated with Central Nervous System Infection Caused by an Extended-Spectrum β-Lactamase-Producing Klebsiella pneumoniae Harboring Hypervirulence-Associated Genes.

BACKGROUND: Central nervous system (CNS) infections caused by Klebsiella pneumoniae harboring hypervirulence-associated genes usually arise from metastatic dissemination from an extracranial focus. Cases lacking an overt extracranial source remain uncommon. Furthermore, the spontaneous development of tension pneumocephalus in this context is exceptionally rare. CASE PRESENTATION: We report a fatal case of a 49-year-old female with a 40-year history of polycystic liver and kidney disease who presented with fulminant meningoencephalitis. Despite aggressive systemic meropenem therapy and neuroprotective measures, she developed refractory intracranial hypertension (780 mmH2O) and rapidly progressive tension pneumocephalus without evidence of neurotrauma or external anatomical breach. Blood and cerebrospinal fluid (CSF) cultures, alongside CSF metagenomic next-generation sequencing (mNGS), identified an extended-spectrum β-lactamase (ESBL)-producing K. pneumoniae. The isolate exhibited a hypermucoviscous phenotype and harbored multiple hypervirulence-associated genes (eg, rmpA, iucA, and iroB) alongside resistance determinants (CTX-M-15-like and AAC(6')-Ib-cr), supporting a probable convergent phenotype. The patient ultimately died from irreversible multiple organ dysfunction syndrome on day 7. CONCLUSION: The rapid evolution of tension pneumocephalus in this case highlights the potential for abrupt neurological deterioration in CNS infections associated with convergent K. pneumoniae phenotypes. While the exact etiology of intracranial gas is likely multifactorial, this case underscores the critical need to integrate phenotypic assays with molecular diagnostics to identify hypervirulence, while maintaining rigorous differential diagnoses for spontaneous pneumocephalus in the neurocritical care setting.