A 54-year-old male, five months postorthotopic
heart transplantation, presented with intermittent
fevers,
headaches, and "soupy" stools. Prior to presentation, he had low-level cytomegalovirus (CMV)
viremia for two straight weeks. Given his immunosuppression,
diarrhea, and low-level CMV
viremia, he was presumed to have cytomegalovirus and/or C. difficile
colitis and treated empirically for both on hospital day one. However, he developed
neck pain/stiffness, diaphoresis, and worsening
fevers on hospital day three. Blood cultures eventually grew Listeria monocytogenes; MRI of the brain with
gadolinium showed left brain
meningoencephalitis with early
cerebral abscess formation. Lumbar puncture revealed elevated opening pressure, CSF neutrophilic
pleocytosis, and elevated CSF
protein and
lactate but negative gram
stain and cultures. First-line agent for
Listeria meningoencephalitis is
ampicillin. However, he reported
amoxicillin allergy. Desensitization to
ampicillin failed because
ampicillin was too unstable per the allergist. He was therefore treated with
penicillin monotherapy for eight weeks with complete resolution of his brain lesions and without any residual
neurologic deficits.