Differential Diagnosis for Enthesitis and Back Pain in a Young Person
Single Most Likely Diagnosis
- Ankylosing Spondylitis (AS): This is a form of arthritis that primarily affects the spine, although other joints can also be involved. It causes inflammation of the spinal joints (vertebrae) that can lead to severe, chronic pain and discomfort. Enthesitis, which is inflammation of the sites where tendons or ligaments insert into the bone, is a hallmark of AS, making it a likely diagnosis for a young person presenting with enthesitis and back pain.
Other Likely Diagnoses
- Reactive Arthritis: This form of arthritis occurs as a reaction to an infection elsewhere in the body, often in the gastrointestinal tract or the urethra. It can cause back pain, enthesitis, and arthritis, especially in young adults.
- Psoriatic Arthritis: A type of arthritis that occurs in some people with psoriasis, characterized by joint pain, swelling, and sometimes enthesitis. Back pain can also be a feature, especially if the spine is involved.
- Inflammatory Bowel Disease (IBD)-associated Arthritis: Both Crohn's disease and ulcerative colitis can be associated with peripheral arthritis and axial involvement, including back pain and enthesitis.
Do Not Miss Diagnoses
- Infectious Spondylodiscitis: An infection of the intervertebral disc space and the adjacent vertebrae, which can present with back pain and may mimic inflammatory back pain. It's crucial to identify this condition due to its need for specific antibiotic treatment.
- Spinal Tumors: Although rare, tumors of the spine can cause back pain and may lead to enthesitis if they involve the areas where tendons or ligaments attach to bone. Early detection is critical for effective management.
- Osteoporosis with Fracture: Especially in young individuals with risk factors such as long-term steroid use, osteoporosis can lead to vertebral fractures, causing back pain.
Rare Diagnoses
- Sarcoidosis: A condition characterized by the growth of granulomas (inflammatory cells) in various parts of the body, including the spine, which can lead to back pain and enthesitis.
- Relapsing Polychondritis: A rare disorder that causes inflammation of cartilage and other tissues, which can involve the spine and lead to back pain.
- Enteropathic Arthritis due to Whipple's Disease: A rare, systemic bacterial infection that can cause arthritis, including back pain, among other symptoms.
Each of these diagnoses has distinct features and implications for treatment, emphasizing the importance of a thorough diagnostic workup for young individuals presenting with enthesitis and back pain.