Clinical and immunological aspects of neurological diseases associated to HTLV-I

THESES

Clinical and Immunological Aspects of Neurological Diseases Associated to HTLV-I (Abstract)^*. Dissertation. Salvador, 2003.

André Muniz^**

Human T-lymphotropic virus type I (HTLV-I) is the etiological agent of HTLV-I Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP), Adult T Cell Leukemia (ATL), and other systemic diseases mediated by the immune response. The HTLV-I infection is endemic in several regions of the world and also in Brazil, especially in the States of Bahia, Pernambuco and Pará.

The objective of the present study was to identify clinical and immunological markers associated with occurrence and severity of HAM/TSP.

A cross-sectional descriptive clinical and immunological study was performed including 237 HTLV-I infected individuals. These patients were assessed using standardized questionnaires and neurological exam. They were classified according to two neurological scales: Expanded Disability Status Scale (EDSS) and Osame's Motor Disability Score (OMDS).

Thirty-seven patients had an EDSS > 3 and OMDS > 1. There was a direct correlation between the degree of neurological disability assessed by OMDS and EDSS (r_s=0.857; p<0.001). There was also a direct correlation between the time of the initial signs of HAM/TSP and the degree of neurological disability assessed by OMDS (r_s=0.406; p=0.014) and EDSS (r_s=0.511; p=0.001).

A marked spontaneous proliferation was observed in peripheral blood mononuclear cells (PBMC) from HAM/TSP patients (n=9) as compared with HTLV-I asymptomatic carriers (n=11), p=0.006; Mann-Whitney U test. Higher levels of interferon (IFN)-g were detected in unstimulated PBMC from HAM/TSP patients (n=21) as compared with asymptomatic HTLV-I positive individuals (n=38), p<0.0001; Mann-Whitney U test.

No correlation was observed between pro-inflammatory cytokine levels and neurological disability or time of HAM/TSP onset. There was a direct correlation between IFN-g and interleukin (IL)-5 levels (r_s=0.560; p<0.05) as well as between tumor necrosis factor (TNF)-a and IL-10 levels (r_s=0.563; p<0.05).

The data of the present study show the validity of the neurological scales (OMDS and EDSS) to classify the degree of neurological disability in HTLV-I carriers, suggest the progressive behavior of HAM/TSP, and show that IFN-g in PBMC supernatants are markers of HAM/TSP and may play a role in the immunopathogenesis of the disease.

Key words: human T- lymphotropic virus 1, nervous system diseases, cytokines.

*

Aspectos clínicos e imunológicos de doenças neurológicas associadas ao HTLV-I (Resumo). Dissertação de Mestrado, Faculdade de Medicina da Universidade Federal da Bahia (Área: Imunologia Clínica). Orientadora: Amélia Ribeiro de Jesus.

**

Address: Rua Hosannah de Oliveira 112/503, 41815-215 Salvador BA, Brasil.

Publication Dates

• Publication in this collection
  19 Sept 2003
• Date of issue
  Sept 2003