Overview
Tropical spastic paraparesis (TSP), also known as HTLV-1-associated myelopathy (HAM), is a chronic disease of the spinal cord caused by infection with the human T-lymphotropic virus type 1 (HTLV-1). This virus slowly damages the nerves in the spinal cord, particularly those that control leg movement and bladder function. The disease is not inherited genetically but is acquired through infection, which can spread through breastfeeding, sexual contact, blood transfusions, or sharing needles. The main symptoms include progressive stiffness and weakness in both legs, making walking increasingly difficult over time. People often notice that their legs feel heavy, they trip more easily, and they develop problems with bladder control such as urgency or incontinence. Low back pain and tingling or numbness in the legs are also common. Symptoms usually develop slowly over months to years. There is currently no cure for tropical spastic paraparesis. Treatment focuses on managing symptoms and slowing disease progression. Corticosteroids and other immune-modulating medications may help reduce inflammation. Physical therapy plays an important role in maintaining mobility and strength. Medications can also help manage bladder problems and muscle spasticity. While the disease is progressive, the rate of decline varies greatly from person to person, and many people maintain the ability to walk with assistance for many years.
Also known as:
Key symptoms:
Progressive leg stiffness and weaknessDifficulty walkingBladder urgency or incontinenceLow back painTingling or numbness in the legsMuscle spasms in the legsConstipationSexual dysfunctionLeg heaviness or fatigueFrequent falls or trippingPain in the legsDifficulty with bowel controlOveractive reflexes in the legs
Sporadic
Usually appears on its own, not inherited from a parent
Adult
Begins in adulthood (age 18 or older)
FDA & Trial Timeline
5 eventsThe University of Hong Kong — NA
Guangdong Provincial People's Hospital — NA
National Institute of Neurological Disorders and Stroke (NINDS) — PHASE1, PHASE2
National Institute of Neurological Disorders and Stroke (NINDS)
Data sourced from FDA regulatory filings and ClinicalTrials.gov. Updated periodically.
Treatments
No FDA-approved treatments are currently listed for Tropical spastic paraparesis.
2 clinical trialsare actively recruiting — trials can provide access to cutting-edge therapies.
View clinical trials →Treatment Centers
8 centersBaylor College of Medicine Rare Disease Center ↗
Baylor College of Medicine
📍 Houston, TX
🏥 NORDStanford Medicine Rare Disease Center ↗
Stanford Medicine
📍 Stanford, CA
🔬 UDNNIH Clinical Center Undiagnosed Diseases Program ↗
National Institutes of Health
📍 Bethesda, MD
🔬 UDNUCLA UDN Clinical Site ↗
UCLA Health
📍 Los Angeles, CA
🔬 UDNBaylor College of Medicine UDN Clinical Site ↗
Baylor College of Medicine
📍 Houston, TX
🔬 UDNHarvard/MGH UDN Clinical Site ↗
Massachusetts General Hospital
📍 Boston, MA
🏥 NORDMayo Clinic Center for Individualized Medicine ↗
Mayo Clinic
📍 Rochester, MN
👤 Mayo Clinic Center for Individualized Medicine
🏥 NORDUCLA Rare Disease Day Program ↗
UCLA Health
📍 Los Angeles, CA
Travel Grants
No travel grants are currently matched to Tropical spastic paraparesis.
Community
No community posts yet. Be the first to share your experience with Tropical spastic paraparesis.
Start the conversation →Latest news about Tropical spastic paraparesis
Disease timeline:
New recruiting trial: Effectiveness and Safety of Adjuvant Software Based on Virtual Reality for Post-thoracoscopic Surgery Pain
A new clinical trial is recruiting patients for Tropical spastic paraparesis
New recruiting trial: Agilis RF TSP Early Feasibility Study
A new clinical trial is recruiting patients for Tropical spastic paraparesis
New recruiting trial: Teriflunomide in HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis
A new clinical trial is recruiting patients for Tropical spastic paraparesis
Caregiver Resources
NORD Caregiver Resources
Support, advocacy, and financial assistance for caregivers of rare disease patients.
Mental Health Support
Rare disease caregiving can be isolating. Connect with counseling and peer support.
Family & Caregiver Grants
Financial assistance programs specifically for caregivers of rare disease patients.
Social Security Disability
Learn how rare disease patients may qualify for SSDI/SSI benefits.
Questions for your doctor
Bring these to your next appointment
- Q1.How quickly is my disease likely to progress, and what factors affect this?,What treatments are available to slow the progression of my symptoms?,Should my family members or sexual partners be tested for HTLV-1?,What type of physical therapy program would be most helpful for me?,Are there any clinical trials I might be eligible for?,What can I do to manage my bladder symptoms more effectively?,How can I reduce my risk of passing HTLV-1 to others?
Common questions about Tropical spastic paraparesis
What is Tropical spastic paraparesis?
Tropical spastic paraparesis (TSP), also known as HTLV-1-associated myelopathy (HAM), is a chronic disease of the spinal cord caused by infection with the human T-lymphotropic virus type 1 (HTLV-1). This virus slowly damages the nerves in the spinal cord, particularly those that control leg movement and bladder function. The disease is not inherited genetically but is acquired through infection, which can spread through breastfeeding, sexual contact, blood transfusions, or sharing needles. The main symptoms include progressive stiffness and weakness in both legs, making walking increasingly d
How is Tropical spastic paraparesis inherited?
Tropical spastic paraparesis follows a sporadic inheritance pattern. Genetic counseling can help families understand recurrence risk and testing options.
At what age does Tropical spastic paraparesis typically begin?
Typical onset of Tropical spastic paraparesis is adult. Age of onset can vary across affected individuals.
Are there clinical trials for Tropical spastic paraparesis?
Yes — 2 recruiting clinical trials are currently listed for Tropical spastic paraparesis on UniteRare. See the clinical trials section on this page for phase, sponsor, and site details sourced from ClinicalTrials.gov.
Which specialists treat Tropical spastic paraparesis?
25 specialists and care centers treating Tropical spastic paraparesis are listed on UniteRare, sourced from ClinicalTrials.gov principal investigators, published research, and the NPPES NPI registry.