Tropical spastic paraparesis


Tropical spastic paraparesis, is a medical condition that causes weakness, muscle spasms, and sensory disturbance by human T-lymphotropic virus resulting in paraparesis, weakness of the legs. As the name suggests, it is most common in tropical regions, including the Caribbean. Blood transfusion products are screened for HTLV-1 antibodies, as a preventive measure.

Signs and symptoms

Some of the signs of Tropical spastic paraparesis are:
Individuals with TSP may also exhibit uveitis, arthritis, pulmonary lymphocytic alveolitis, polymyositis, keratoconjunctivitis sicca, and infectious dermatitis.
HTLV-1 can be transmitted via breastfeeding, sexual contact, via blood contact.

Pathogenesis

In Tropical spastic paraparesis, HTLV-1 shows elevated cellular acquired immune response as well as high production of proinflammatory cytokines. IFN overexpression has been demonstrated as well. Also the number of NK cells is diminished.

Diagnosis

Among the methods of diagnosing tropical spastic paraparesis are MRI and lumbar puncture.

Treatment

Treatment of TSP involves corticosteroids to help with inflammation. Though any success with corticosteroids is short-lived, with symptoms worsened as the dosage is reduced. A synthetic derivative, 17-alpha-ethinyltestosterone, can be used to treat Tropical spastic paraparesis, improvement in motor and bladder function was reported but not sustainable.
Mogamulizumab, an anti-CCR4 IgG1 monoclonal antibody, is also being researched as a possible treatment for Tropical spastic paraparesis. The antibody reduces HTLV-1 proviral load and production of proinflammatory cytokines. Valproic acid has also succeeded in reducing the proviral load of HTLV-1. A further combination of valproic acid and zidovudine has demonstrated a decrease in proviral loads.

Prognosis

The prognosis for Tropical spastic paraparesis indicates some improvement in a percentage of cases due to immunosuppressive treatment. A higher percentage will eventually lose the ability to walk within a ten-year interval.

History

For several decades, the term tropical spastic paraparesis was used to describe a chronic and progressive clinical syndrome that affected adults living in equatorial areas of the world. This condition was initially thought to be associated with infectious agents and with chronic nutritional deficiencies or exposure to potentially toxic foods.
Tropical myeloneuropathies are classified as two separate syndromes: tropical ataxic neuropathy and tropical spastic paraparesis. They are placed together because they are found in tropical countries, although tropical spastic paraparesis
has occurred in temperate countries.