Rhombencephalitis caused by Listeria monocytogenes with striking involvement of trigeminal nerve on MR imaging

Romboencefalite causada por Listeria monocytogenes com envolvimento do nervo trigêmio na RNM

LETTERS

Rhombencephalitis caused by Listeria monocytogenes with striking involvement of trigeminal nerve on MR imaging

Romboencefalite causada por Listeria monocytogenes com envolvimento do nervo trigêmio na RNM

Adriana Moro^I; Pedro Henrique de Campos Albino^I; Alisson Pittol Bresciani^I; Marcus Victor de Oliveira^I; Melina Moré Bertotti^II; Rafael Martins Ferreira^III; Luiz Paulo Queiroz^IV

^IResident of Neurology, Neurology Department, Hospital Governador Celso Ramos, Florianópolis SC, Brazil

^IIResident of Neurosurgery, Neurology Department, Hospital Governador Celso Ramos, Florianópolis SC, Brazil

^IIIMD, Neuroradiologist, Associate Professor of Neurology Residency Program, Neurology Department, Hospital Governador Celso Ramos, Florianópolis SC, Brazil

^IVMD, PhD, Neurologist, Neurology Residency Program Preceptor, Head of the Neurology Residency, Neurology Department, Hospital Governador Celso Ramos, Florianópolis SC, Brazil

^{Correspondence}

The listeria rhombencephalitis is an uncommon and severe infection of the brainstem, usually occurring in healthy adults with a typical biphasic picture ¹. A pro-drome of fever, headache, nausea and vomiting followed by abrupt neurological symptoms². A stiff neck is present in half of the cases and positive culture in cerebrospinal fluid (CSF) in about 40% of the cases. Mortality is high and serious sequelae are common². We report a case of a patient with involvement of the brainstem and a favor-able outcome.

CASE

A 65-year-old man presented with pain in right jaw, nuchal pain and right facial palsy, following gastroen-teritis. The neurological exam revealed a palsy of VI and VII right cranial nerves, right hemifacial hypoesthesia, strength grade 3, hyperreflexia, Babinski sign bilaterally, neck stiffness and axial ataxia. The CSF showed: 100 cells/mm³ (95% lymphocytes); protein 63 mg/dL; glucose 95 mg/dL; negative cultures for bacteria, fungi and acid-fast bacilli. Magnetic resonance imaging (MRI) showed bilateral and asymmetric lesions involving the brainstem with a striking enhancement along the right trigeminal nerve and ipsilateral spinal trigeminal nucleus (Figure).

With the diagnostic suspicion of herpes zoster en-cephalitis, the patient was treated with acyclovir and was transferred to an intensive care unit due to respiratory failure 24 hours later.

Blood cultures showed the presence of Listeria mono-cytogenes later. Acyclovir was interrupted and intrave-nous ampicillin plus dexamethasone were initiated. The infection improved but the patient remained with severe neurological sequelae. The second MRI showed multiple hemorrhagic foci in the cerebellar hemispheres, brain-stem, basal ganglia nuclei and capsular region. Mild signal abnormalities remained in the brainstem and cer-ebellar peduncles.

At four months he began walking and making sounds that were gradually replaced by full speech.

DISCUSSION

Listeria monocytogenes is a Gram-positive organism transmitted by consumption of contaminated food. The diagnosis can be delayed if no meningeal signs are pre-sented in the beginning of the disease⁴ as in our patient. Cultures of CSF and blood are positive in 41% and 61% of cases, respectively³. In our case only the blood cul-ture was positive.

The CSF typically reveals an increased leukocyte count, with predominance of polymorphonuclear cells, increased protein, and normal glucose levels⁵. Our pa-tient presented only a predominance of lymphomono-nuclear cells, maybe due to precoceous CSF examination.

MRI is important for the early detection of paren-chymal lesions, therefore, being crucial for early diag-nosis and follow-up⁵. The patient presented extensive le sions involving the brainstem and, as far as we know, such striking involvement of trigeminal nerve extending to its trigeminal spinal nucleus has never been reported. It may mimic trigeminal nerve involvement with herpes zoster.

For the treatment, ampicillin and gentamicin are the most recommended combination. Dexamethasone is an important agent in treating most CNS infection because of its powerfull anti-inflammatory activity and reduction of cerebral edema⁴.

Listeria monocytogenes encephalitis should be in-cluded in the differential diagnosis of rombencephalitis in elderly people with non- typical bacterial CSF founds. Involvement of trigeminal nerve and spinal trigeminal nucleus can occur in these cases, mimicking cases of herpes zoster infection.

Received 26 February 2011

Received in final form 13 March 2011

Accepted 21 March 2011

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• 2. Uldry PA, Kuntzer T, Bogousslavsky J, et al. Early symptoms and outcome of Listeria monocytogenes rhombencephalitis: 14 adult cases. J Neurol 1993;240:235-242.
• 3. Armstrong RW, Fung PC. Brainstem encephalitis (rhombencephalitis) due to Listeria monocytogenes: case report and review. Clin Infect Dis 1993; 16:689-702.
• 4. Popescu GA, Saquepe'e M, Poisson D, Prazuck T. Treatment difficulties of a listerial rhombencephalitis in an adult patient allergic to penicillins.
• 5. Alper G, Knepper L, Kanal E. MR Findings in Listerial rhombencephalitis. AJNR 1996;17:593-596.

Publication Dates

• Publication in this collection
  19 July 2012
• Date of issue
  June 2011