IMMUNE-MEDIATED NEUROLOGICAL COMPLICATIONS AND DENGUE

CASE PRESENTATION: CASE 1: Woman, 50 years old, after 15 days of dengue infection confirmed by detection of the NS1 antigen in the blood, began to present intense asthenia, paresthesia and ascending paresia. He performed electroneuromyography compatible with acute demyelinating polyradiculoneuritis - Guillain-Barré Syndrome, and liquor with proteino-cytological dissociation. After treatment with human immunoglobulin, he showed significant improvement in symptoms. CASE 2: Man, 23 years old, had dengue virus infection confirmed by serology. After 20 days, it evolved with paresthesia and upward paresis, hypoesthesia with a sensory level on T1 and urinary retention. In magnetic resonance imaging of the skull and cervical spine, multiple lesions with hypersignal in T2/FLAIR are evident in the white, supra and infratentorial substance, in the brainstem, in the cervical and thoracic spinal cord, with acute disseminated encephalomyelitis (ADEM) being the first diagnostic hypothesis. In the cerebrospinal fluid, pleocytosis, proteinorrhachia and IgM immunoglobulin reagent for the dengue virus were observed.

DISCUSSION: The neuropathogenesis of dengue infection is due to the direct invasion of the virus into the central nervous system, immune-mediated reactions or metabolic changes. The neurological complications of dengue include encephalopathy, meningitis, myelitis, ADEM, optic neuromyelitis, optic neuritis, Guillain-Barré syndrome and neuro-ophthalmic complications. After infection with the dengue virus, our patients had neurological complications in the peripheral nervous system and the central nervous system, both of which are probably secondary to the immune-mediated mechanisms.

FINAL CONSIDERATIONS: The dengue virus is considered non-neurotropic, however, the presence of viral particles in the cerebrospinal fluid, as well as damage to the blood-brain barrier, suggest viral neurotropism. Acute febrile diseases with neurological manifestations should be included in the diagnostic investigation, especially in endemic regions of arboviruses, such as tropical and subtropical countries.