Multiphasic disseminated encephalomyelitis associated with herpes virus infection in a patient with TLR3 deficiency

We report a case of a 14-year-old girl that presented headache, amaurosis, drowsiness, fever, vomiting and diffuse reduction of muscle strength. She had been diagnosed with ADEM one year before and had a previous diagnosis of Toll-Like 3 receptor deficiency. Cerebrospinal fluid analysis revealed pleocytosis (28/mm³, 12/mm³ red blood cells, 70% lymphocytes cells, 2% monocytes cells, 28% neutrophils), normal total protein (38 pg/mL) and normal glucose level (53/mm³). Studies for CSF oligoclonal bands and serum anti-MOG were negative but polymerase chain reaction (PCR) testing was positive for herpes virus 1. In the first ADEM episode, PCR for herpes virus was also positive. Magnetic resonance imaging (MRI) of the brain revealed disseminated hyperintense lesions on T2-weighted and FLAIR images in the white matter of frontal, parietal and temporal lobes, corresponding to extensive asymmetric areas of demyelination that produced mass effect and gadolinium enhancement. Electroencephalography demonstrated irregular diffuse and generalized slow-wave activity with predominance in frontal region. The diagnosis of multiphasic disseminated encephalomyelitis (MDEM) triggered by herpes simplex virus was made. Herpes virus is a neurotropic virus that can cause a wide variety of neurological infection-triggered autoimmune disorders and that is particularly damaging to the central nervous system in situations of impaired immune system. TLR3 is expressed in astrocytes and dendritic cells of the central nervous system and is essential for natural immunity to herpes simplex. TLR3-deficient patients have already been described with herpes simplex encephalitis. TLR3 deficiency may predispose and explain autoimmune and demyelinating manifestations induced by herpes virus. The association of multiphasic disseminated encephalomyelitis triggered by herpes virus in a patient with TLR3 deficiency has not been previously reported in the literature.

Atypical presentations of acute disseminated encephalomyelitis (ADEM) in HIV infection

Acute disseminated encephalomyelitis is a monophasic demyelinating disorder of the central nervous system associated with various viral infections including HIV infection. We present the findings of seven HIV-infected patients with mild to moderate immunosuppression presenting with atypical features. Four patients had a multiphasic course; three patients had tumefactive lesions, and two patients had corpus callosum lesions. Two patients with the multiphasic course also had tumefactive lesions. Their clinical and radiological findings are presented. Despite the few cases, we propose that the dysimmune process lying between marked immunosuppression (CD4 < 200 cells/μL) and normal CD4 counts (CD4 > 500 cells/μL) might be responsible for these atypical presentations.