Introduction: Spontaneous bacterial meningitis infections secondary to gram-negative bacilli are an infrequent occurrence in the immunocompetent adult population. Amongst the most common gram-negative bacilli causing adult bacterial meningitis include Klebsiella pneumoniae, Pseudomonas aeruginosa, and Actinetobacter, with E.coli meningitis as the rarest. E.coli meningitis typically occurs in three settings: neonatal meningitis, postoperative meningitis, and spontaneous meningitis. Spontaneous meningitis typically is seen in immunocompromised patients, and rarely in immunocompetent patients. Between 1945 to 2017, there was a total of 45 confirmed cases of spontaneous E.coli meningitis in immunocompetent patients. Given that these individuals often have higher mortality rates, of around twenty times greater than other meningitis infections, early identification of symptoms and presentation is imperative to improving outcomes for our patients.

Case Presentation: A 55-year-old female with a past medical history of polymorphic ventricular tachycardia status post dual chamber implantable cardioverter defibrillator, hypertension, and type III spinal meningeal cyst presented with right-sided facial droop, dysarthria, headache, and neck stiffness for 3 hours. On physical examination, heart rate was 110 beats/min, temperature was 102.3F, and Glasgow coma score of 12. The patient was stroke alerted with computed tomography of the head without acute intracranial hemorrhage. Ultrasound of the bilateral orbits was obtained, which revealed increased optic nerve sheath diameter bilaterally (> 0.7cm). An infectious workup was collected. Blood cultures were negative. A lumbar puncture was performed with findings significant for elevated leukocytes, elevated protein, decreased glucose, and gram stain significant for gram-negative rods. Cerebral spinal fluid was negative for herpes simplex virus. Urinalysis was positive for leukocyte esterase with urine culture growing Escherichia coli (E.coli). Computed tomography of the abdomen/pelvis was negative for intra-abdominal findings. The patient was started on antibiotics and de-escalated to Ceftriaxone once sensitivity confirmed pan-sensitive E.coli.

Final/Working Diagnosis: Infectious disease was consulted with suspicion of E.coli meningitis etiology from a urinary source translocated to the central nervous system through the disruption of the blood-brain barrier as a result of her meningeal cyst.

Management/Outcomes/Followup: During the patient’s hospitalization, she continued to clinically improve with symptoms resolving. The patient was discharged home on Levaquin 750 mg daily for three weeks, and follow-up with Infectious Disease outpatient.

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