Resumen de Inmunohistoquímica de los cambios degenerativos del sistema nervioso central en paraparesias espásticas asociadas al virus linfotrópico humanoTtipol(HTLV-l)
Luis Cartier R, Carmen Vergara R, María Antonieta Valenzuela P
Background: Human T lymphotropic virus type I is associated with tropical spastic paraparesis, that is a chronic and progressive disease which damages specially the cortiespinal tracts. The pathogenesis of this degenerative process remains unknown. Aim: To identify histopathological aspects that could suggest a pathogenic hypothesis we studied immunohistochemical features in spinal cords obtained from patients that died due to progressive spastic paraparesis. Patients and Methods: Five males and five females, who died between 1990 and 2000, with a mean age of 52 years and mean disease duration of 8.6, were studied. All had a complete clinical and virological diagnosis. Samples were obtained from the frontal motor cortex and spinal cord (cervical, dorsal and lumbar segments), were fixed in formol (10%), included in paraffin, and stained with Haematoxylin and Luxol-fast-blue. Immunohistochemical study was made with anti-neurofilament antibodies 1:100 (M0762, DAKO), anti-APP 1:20 (Rabbit Pre Amyloid protein 51-2700 ZYMED), anti-tau 1:100 (A0024DAKO) and anti-ubiquitine 1:50 (NCL UBIQm Novocastra). Results: All cases had demyelinization and axonal loss in the cortico-spinal tracts; distal and segmental demyelinization of Goll tract; axonal thickening, amyloid precursor protein deposits in the white matter; tau protein aggregation in the spinal cord oligodendrocytes; axonal ubiquitination of sensitive and motor tracts, and subcortical white matter. Neurona! injury was absent. Conclusions: The systematic damage of motor and sensitive tracts of the spinal-cord and the absence of neurona! damage, defines a degenerative process limited to axons. This central axonopathie could be caused by a disturbance of axoplasmic transport
