Neuroconduction examination in patients with HTLV-I associated myelopathy

Estudo da neurocondução em pacientes com mielopatia pelo HTLV-I

THESES

NEUROCONDUCTION EXAMINATION IN PATIENTS WITH HTLV-I ASSOCIATED MYELOPATHY (ABSTRACT)^*. DISSERTATION. NITERÓI, 1999.

CRISTIANE RIBEIRO DE ALMEIDA AFONSO ^**

The main neurological manifestation of the Human T-Cell Lymphotropic Virus Type I (HTLV-I) is spastic paraparesis, of progressive nature, also known as HTLV-I associated myelopathy (HAM) or tropical spastic paraparesis. Since the discovery of the virus, other neurological manifestations, like polymyositis and peripheral neuropathy, have been associated to it.

A group of 54 individuals positive to HTLV-I associated myelopathy were surveyed from the electrophysiological point of view (neuroconduction). The evaluated nerves were: the radial, the ulnar and the median from the upper limbs; and the fibular, the tibial and the sural, from the lower limbs. From the neuroconduction examination, we observed that the peripheral nerve is compromised in 68.5% of the patients. In this group, 37.8% presented a mononeuropathy, the median nerve was the most compromised, 24.4% manifested multiple mononeuropathy, and 37.8% presented polyneuropathy (84.6% presented sensorymotor polyneuropathy and 15.4% presented exclusively a motor polyneuropathy; 61.5% manifested a mixed polyneuropathy, with 30.8% indicating that myelin is compromised and 7.7% presenting axonal polyneuropathy).

The most frequent detected electrophysiological alterations were increased latency on the sural nerve (30.2%) followed by the decrease median motor amplitude (25.6%).

Statistical analyses were performed comparing two samples using the Student t test: Sample 1 (patients with myelopathy presenting alterations in the neuroconduction exam) and Sample 2 (patients with myelopathy not presenting alterations in the neuroconduction examination). Statistical results showed that the association of myelopathy to neuroconduction alterations was not casual. All the evaluated parameters showed significant statistical values, with the only exception being the fibular nerve latency.

We conclude that electrophysiological compromising of the peripheral nerve is frequent in patients with HTLV-I associated myelopathy. Furthermore, electrophysiological compromising can arise even when the patient does not present clinical manifestations denoting this kind of problem. Hence, the study of the neuroconduction has to become a routine for patients with HTLV-I.

KEY WORDS: nerve conduction, HTLV-I, peripheral neuropathy.

** Address: Rua Santa Amelia 50 / 1512 Bl-02, 20260-030 Rio de Janeiro RJ, Brasil. E-mail: [e-mail]

*

Estudo da neurocondução em pacientes com mielopatia pelo HTLV-I (Resumo). Dissertação de Mestrado, Universidade Federal Fluminense (Área: Neurologia). Orientador: Osvaldo José Moreira do Nascimento.

Publication Dates

• Publication in this collection
  06 Dec 2000
• Date of issue
  June 2000