What is tropical spastic paraparesis?
Tropical spastic paraparesis has been recognized clinically for many years in tropical areas and Japan.
It is characterized by a chronic course in which mild to severe leg weakness develops with increased muscle tone and extensor plantar responses.
The upper limbs may become hyperreflexic, but do not usually show weakness. Urinary symptoms are common such as increased urgency and incontinence due to neurogenic bladder.
One-half of patients have posterior column sensory signs, and 15% have optic nerve involvement.
The condition is caused by infection with a retrovirus, HTLV-1, which infects approximately 10 to 20 million people worldwide.
Of infected individuals, 0.25% to 3.8% will develop tropical spastic paraparesis, otherwise known as HTLV 1-associated myelopathy.