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Subacute progression of human T-lymphotropic virus type I-associated myelopathy/tropical spastic paraparesis

Marco A Lima1, Ramza C Harab, Doris Schor

  • 1The Reference Center on Neuroinfections and HTLV, Instituto de Pesquisa Clínica Evandro Chagas (IPEC), Fundação Oswaldo Cruz, Avenida Brasil 4365, Rio de Janeiro, RJ, Brazil. mlima@ipec.fiocruz.br

Journal of Neurovirology
|November 13, 2007
PubMed

Insights

A rare subacute form of human T-lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) affects 7.9% of patients. This aggressive HAM/TSP progression is not linked to higher HTLV-I proviral loads.

Area of Science:

  • Neurology
  • Infectious Diseases
  • Virology

Background:

  • Human T-lymphotropic virus type I (HTLV-I)-associated myelopathy/tropical spastic paraparesis (HAM/TSP) is typically a chronic neurological disorder.
  • However, a rapid, subacute disease course has been observed in a subset of patients.

Purpose of the Study:

  • To describe the clinical characteristics of HAM/TSP in a Brazilian cohort.
  • To determine the prevalence of subacute HAM/TSP, defined by wheelchair dependency within 2 years of symptom onset.
  • To compare HTLV-I proviral loads between patients with subacute and chronic HAM/TSP.

Main Methods:

  • Retrospective analysis of a Brazilian cohort of HAM/TSP patients.
  • Definition of subacute progression: wheelchair requirement within 2 years of symptom onset.
  • Quantification of HTLV-I proviral loads using real-time polymerase chain reaction (PCR).

Main Results:

  • Seven out of 88 patients (7.9%) exhibited a subacute HAM/TSP progression.
  • All patients with subacute progression were female, with 5/7 acquiring HTLV-I sexually.
  • No significant difference in HTLV-I proviral loads was found between the subacute and chronic HAM/TSP groups (P = .68).

Conclusions:

  • A distinct subgroup of HAM/TSP patients experiences rapid disease progression, independent of HTLV-I proviral load.
  • Early identification of subacute HAM/TSP is crucial for timely intervention.
  • Prompt immunosuppressive treatment may offer benefits for patients with aggressive HAM/TSP.

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