Jamaican neuropathy: an electrophysiological study

HTLV-1 and neurological conditions: when to suspect and when to order a diagnostic test for HTLV-1 infection?

HTLV-1 is a retrovirus associated with a myriad of clinical conditions, especially hematological and neurological ones. Regarding nervous system diseases, it is of utmost importance to select those cases in which HTLV-1 infection could really be associated. This is particularly true for patients from endemic areas and for HIV-infected patients and drug users, since that these groups are at a higher risk for HTLV infection. This caution in selecting neurological patients for HTLV diagnostic tests is justified by the fact that in some circumstances the seropositivity may merely represent an epiphenomenon. In this paper we enroll some neurological conditions that have been associated with HTLV-1/2 infection in the literature and discuss the real need for HTLV-1/2 diagnostic tests in each one. Because HIV/HTLV-co-infected patients seem to be at an increased risk for neurological diseases development, a special consideration about this matter is also made.

The myeloneuropathies of Jamaica

This article summarizes the present state of knowledge of TSP/HAM as it is seen in Jamaica. It reviews the historical and clinical aspects of the disease, and shows how the discovery of HTLV-I has generated research in several countries and contributed to a better understanding of the disease. It highlights the need for continued collaboration between basic scientists and clinical neurologists in order that the dilemmas relating to therapy and pathogenicity may be successfully addressed.

Peripheral nerve lesions in HTLV-I associated myelopathy (HAM/TSP)

Peripheral nerve dysfunction (PND) was found in as many as 43% of our patients with human T-cell lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM/TSP). To evaluate the PND further we biopsied the sural nerve in 6 patients. The histological features were varying degrees of demyelination, remyelination, axonal atrophy and degeneration, and perineurial fibrosis. "Globule" or "sausage" formation was prominent in two of the specimens. Inflammatory infiltrates were absent. No deposits of IgG, IgM, IgA, or complement were detected in the biopsies. No viral antigen or proviral DNA was detected. It is proposed that the PND and the histological findings noted are part of HTLV-I-associated disease and not an unrelated disorder. The pathogenesis of the PND remains unclear. There was no evidence of direct viral infection. The histological findings could represent primary changes induced by viral-triggered release of soluble factors, such as cytokines or secondary changes to more proximal disease, e.g., root involvement.

AAEM minimonograph #34: polyneuropathy: classification by nerve conduction studies and electromyography

Electrodiagnostic evaluation of patients with suspected polyneuropathy is useful for detecting and documenting peripheral abnormalities, identifying the predominant pathophysiology, and determining the prognosis for certain disorders. The electrodiagnostic classification of polyneuropathy is associated with morphologic correlates and is based upon determining involvement of sensory and motor fibers and distinguishing between predominantly axon loss and demyelinating lesions. Accurate electrodiagnostic classification leads to a more focused and expedient identification of the etiology of polyneuropathy in clinical situations.

Tropical spastic paraparesis. A clinical study of 50 patients from Tumaco (Colombia) and review of the worldwide features of the syndrome

Tropical spastic paraparesis (TSP) is a chronic and slowly progressive endemic myelopathy occurring in geographical isolates in the Caribbean, South India, South Africa, the Seychelles, and Colombia. A detailed clinical and laboratory study was performed on 50 TSP patients from the island of Tumaco (Colombia), in a tropical rain forest area. Most patients were middle-aged blacks, 29 (58%) men and 21 women. In every case, neurological examination confirmed the presence of pyramidal signs in the lower limbs, plus, in 58%, moderate decrease in vibratory perception distally in the feet, bilaterally and symmetrically. Absent ankle jerks were found in 28%. Slow onset and chronic progression were documented in most patients. Positive treponemal serology, from yaws infection in childhood, was found in the serum in 92%, and in 19% also in the cerebrospinal fluid (CSF). No pleocytosis was documented on 27 CSF samples, but increased protein content occurred in 86%, with elevation of gamma-globulins in 78%. Treatment of 20 patients with high doses of penicillin produced no change in the clinical picture. TSP emerges from this review of the literature as a remarkably homogeneous clinical entity worldwide. A retrovirus-human T-lymphotropic virus type 1 (HTLV-1)--has been recently implicated as a possible etiology of the syndrome.