Introduction: Gram negative bacilli cause < 10% of adult meningitis. Klebsiella pneumoniae represents a tiny fraction and is usually postoperative or nosocomial. Otogenic spread from mastoiditis is rarer still. Because diabetic ketoacidosis (DKA) alters sensorium, concomitant meningitis may be overlooked in the ICU. Description: A 56-year-old diabetic woman presented in fulminant DKA and septic shock requiring ICU admission and intubation. She denied recent procedures or systemic infection other than a self-treated earache one week earlier. After metabolic correction she remained febrile and encephalopathic; examination revealed nuchal rigidity and left mastoid tenderness. Empiric antimicrobial therapy was initiated. Lumbar puncture (opening pressure 32 cm H2O) yielded turbid CSF with 1,800 WBC/mm3 (90% neutrophils), protein 420 mg/dL, glucose 10 mg/dL; CSF and blood cultures later grew pan-susceptible Klebsiella pneumoniae. Temporal-bone CT and contrast MRI showed coalescent left mastoiditis with cortical erosion and a 1.5 cm subperiosteal abscess abutting dura, without venous sinus thrombosis or parenchymal abscess. Urgent cortical mastoidectomy evacuated purulent material; mastoid cultures matched the CSF isolate, confirming otogenic spread. She was ultimately discharged home to complete a 21-day course of ceftriaxone, neurologically intact except for mild left high-frequency hearing loss. Discussion: Community-acquired otogenic K. pneumoniae meningitis has been reportedly only sporadically outside East Asia; diabetes and hypermucoviscous serotypes appear contributory. Mortality can exceed 40% when recognition or source control is delayed. This unusual case yields three critical-care lessons: (1) when encephalopathy persists after metabolic derangements normalize, clinicians should re-examine for CNS infection; (2) gram-negative rods on initial CSF smear warrant immediate broad coverage with a third-generation cephalosporin or carbapenem; (3) early temporal-bone imaging plus prompt mastoidectomy are essential for definitive source control in the context of recent ear infection. Vigilance for uncommon but lethal pathogens such as K. pneumoniae, even in community presentations, is imperative in the ICU era of evolving antimicrobial resistance and hypervirulent strains.
Khalek et al. (Sun,) studied this question.