MOG-IgG is rare in AQP4-IgG seronegative NMO phenotype in Brazil.

Background: Neuromyelitis optica spectrum disorder (NMOSD) is a rare autoimmune disease most frequently characterized by a neuromyelitis optica (NMO) phenotype, comprising both simultaneous or sequential optic neuritis (ON) and longitudinally extensive transverse myelitis (LETM). Symptoms of brainstem, diencephalic and cerebral involvement may also occur. While most NMOSD patients test positive for serum aquaporin-4 (AQP4) antibodies, some seronegative patients test positive for oligodendrocyte glycoprotein-IgG (MOG-IgG).

Encephalitis associated with anti-mGluR5 antibodies.

A 30-year-old woman had 5 days of visual hallucinations, nystagmus, memory impairment and mutism. On examination, she was disorientated with reduced attention span, gaze-evoked nystagmus, paratonia and abnormal frontal reflexes. Cerebrospinal fluid (CSF) showed 80 cells, protein 0.

Acute disseminated encephalomyelitis following Saint Louis encephalitis virus infection.

Saint Louis encephalitis virus (SLEV) infection is an arbovirosis associated with a broad spectrum of neurological complications. We present a case of a 55-year-old man hailing from Manaus, a city situated in the heart of the Amazon Rainforest, who exhibited symptoms of vertigo, tremors, urinary and fecal retention, compromised gait, and encephalopathy 3 weeks following SLEV infection. Neuroaxis MRI revealed diffuse, asymmetric, and poorly defined margins hyperintense lesions with peripheral and ring enhancement in subcortical white matter, as well as severe spinal cord involvement.

Neurocysticercosis: diagnosis via metagenomic next-generation sequencing.

A 68-year-old Brazilian woman had 3 months of progressive fatigue, difficulty walking and 18 kg weight loss. On examination, there was gait apraxia and executive dysfunction. MR scan of brain showed communicating hydrocephalus and a cerebrospinal fluid showed 105 white cells/µL (≤5), predominantly lymphocytes, protein of 1.

Neuromyelitis optica spectrum disorder associated with dengue virus infection.

Dengue virus infection is a disease with high incidence in some tropical and subtropical countries. A variety of neurological complications of dengue fever (DF) has been described including two cases with the phenotype of neuromyelitis optica spectrum disorder (NMOSD). However, aquaporin-4 serostatus was unknown or negative in these patients.

Myelitis and cauda equina involvement following dengue fever. A case report and review of the literature.

Dengue fever (DF) is a common arbovirosis in tropical and subtropical countries and may be associated with a wide range of neurological complications. We describe a 41-year-old man who developed weakness in the right arm and lower limbs, paresthesia in the upper and lower limbs, and sphincter disturbance four weeks following DF. Examination disclosed a wheel-chair bound patient with urinary catheter, areflexia in the lower limbs, and a sensation level at T10.