Contributor: Nancy Liu, MD
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A 25 year old female is referred for evaluation of back pain. She has had chronic back pain since high school and thought it was related to injuries since she was active in numerous sports,. During college, she was less physically active in sports, but the back pain persisted. She describes her back stiffness as most severe in the morning upon awakening and after prolonged inactivity, such as sitting in the classroom for an hour. The symptoms last at least for 60 minutes and improve if she stretches, moves, or participates in physical exercise. Her pain is mostly in the lower thoracic region and she describes muscle spasms. She will awaken at night after 3-4 hours of sleep with back pain and will have to walk around. Occasionally, she will have alternating buttock pain as well. Naproxen OTC reduces her stiffness but she is afraid to take them regularly due to concern for toxicity.
What are the typical features of inflammatory back pain?
The characteristics features of inflammatory back pain include: 1) onset of back pain before age 40; 2) insidious in onset; 3)pain that improves with exercise but 4) no improvement with rest; 5) nocturnal pain, especially the second half of the night.
What are other commonly associated features in this diagnosis that should be sought?
Aside from inflammatory back pain, other manifestations include: enthesitis, particularly in the Achilles tendon, plantar fascia, anterior chest wall or iliac crest; shoulder or hip joint involvement; uveitis; aortitis; IgA nephropathy; rarely neurologic involvement; and apical pulmonary fibrosis.
What is the best approach to classify and confirm the diagnosis?
Aside from the history and physical exam, laboratory data has limited utility. Although elevations in inflammatory markers such as erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) are often present, these are nonspecific. Radiographic imaging in early disease can be normal but obtaining sacroiliac (SI) joint, thoracic and lumbar spine films can sometimes reveal characteristic changes (enthesitis at the vertebral body, syndesmophytes, sacroiliac erosions or sclerosis) if symptoms have been of longer duration. MRI with STIR images of the axial spine and SI joints are more sensitive for early inflammatory changes and bone marrow edema. HLA B27 testing is helpful in supporting the diagnosis in a patient with classic inflammatory back symptoms or other associated features (arthritis, dactylitis, heel enthesitis, uveitis, psoriasis, inflammatory bowel disease, elevated inflammatory markers, response to NSAIDs, or family history of spondyloarthropathy (SpA) if radiographic changes are not yet present.
Spondyloarthropathy encompasses a group of diseases: ankylosing spondylitis, non-radiographic axial SpA, undifferentiated SpA, reactive arthritis, SpA associated with psoriasis, inflammatory bowel disease, and juvenile onset SpA.
Another classification proposed by the Assessment of Spondyloarthritis International Society (ASAS) separates this group of diseases into two main clinical classifications: predominantly axial spondyloarthritis or predominantly peripheral spondyloarthritis.
Thus, in this case, the patient would have axial spondyloarthritis or ankylosing spondylitis if there were radiographic changes, or non-radiographic axial SpA if her films Xrays were normal.
A 40 year old male with longstanding psoriatic arthritis on adalimumab for management of skin and joint disease develops increasingly severe mid-back pain. The pain started after lifting a heavy box at work. He describes the pain as constant, unrelieved by positional change and worse with activity. He has tried ibuprofen 800mg three times daily without symptomatic relief. The pain has been increasing in severity. His psoriatic arthritis and skin disease have been in excellent control for the past 6 years on therapy. He denies any fevers but describes malaise for the past week and mild anorexia. He has no radicular symptoms.
What is your differential diagnosis?
Although psoriatic arthritis is one of the spondyloarthropathies that can have associated involvement in the axial spine, it is important to consider the entire history. The patient’s joint disease has been in very good control with adalimumab and it would be unusual to develop new inflammatory back pain on adequate therapy. The sudden onset of pain after lifting a box is concerning for possible mechanical injury or compression fracture. The latter would be unusual in this 40 year old male. However, he also has more generalized symptoms of fever, malaise and has low grade fever on ibuprofen. Given his immunosuppression with adalimumab and evidence of skin breakdown at his elbow, workup for possible infectious cause is strongly indicated.
How would you proceed in evaluating this patient?
General evaluation includes CBC with differential, electrolytes, creatinine, ESR, CRP, blood and urine cultures. If there is swelling of the olecranon bursa, an aspirate and culture can provide possible identification of organism. Radiographs of area of point tenderness is the first imaging test but it is likelyfurther imaging with MRI or CT scan is needed to exclude vertebral osteomyelitis, discitis or paravertebral abcess. Cardiac echo should be ordered to exclude endocarditis.
(Answer questions 1 – 5 on a piece a paper. Find Answer Key at the bottom on the page.)
A 25 year old male has a 6 months history of progressive lower back pain. It began slowly without prior trauma and it is associated with stiffness and pain, particularly in the second portion of the night. He will awaken and need to get up and move around for a period of time before he can return to bed. In the morning, he has prolonged morning stiffness of his back, particularly in the buttock region. The pain will sometimes radiate down towards the posterior knee but never below it and sometimes alternate from one side to the other. He prefers to walk around at work rather than sit at his desk.
1) Which of the following is likely the source of his pain?
A 30 year old female has new onset joint pain and swelling in her right index finger, left wrist, and left ankle of 3 weeks duration. There was no antecedent trauma. She is in good health without any other medical problems. She travelled to Central America for an extended period of time and just returned 2 months ago. She developed an episode of what she presumed was traveler’s diarrhea that was associated with fevers, chills, crampy abdominal pain and loose stools. Her symptoms resolved after a week. Other companions on the same trip also developed similar symptoms. She has tried naproxen 220mg BID with some improvement.
On exam, she is afebrile with normal vital signs. General exam is normal. Joint exam reveals dactylitis of her right index finger, swelling in her left wrist, and medial left ankle which is painful on inversion against resistance.
Laboratories: ESR of 45mm/hr; CRP of 30mg/L (normal <10mg/L); WBC of 13,000 cells/mm3; hgb of 14 gm/dL and hct of 40%. Creatinine, LFTs and urinalysis are normal.
2) What is the most appropriate next step in management of this patient?
A 22 year old previously healthy male developed unilateral uveitis that was treated with topical steroids successfully. 3 months later, he develops onset of left knee pain and swelling that is associated with prolonged morning stiffness that gradually improves by noon. He also notes chest wall pain with inspiration and bilateral heel pain. He denies any rashes, diarrhea or mouth ulcers. There is family history of an uncle with Crohn’s disease.
Physical exam reveals normal vital signs. The general exam is normal. The chest wall is tender at the costochondral junctions. Musculoskeletal exam reveals moderate size left knee effusion that is warm and limited range of motion. The ankles are normal but there is point tenderness and swelling of bilateral Achilles insertion at the retrocalcaneal region.
3) The most likely diagnosis is:
4) Psoriatic arthritis has a wide range of clinical features that are clinically present in other spondyloarthropathies. The one feature that is unique and characteristic in psoriatic arthritis is:
Tumor necrosis factor alpha inhibitors (TNFi) are the predominant class of biologic medications used to treat ankylosing spondylitis, psoriatic arthritis, and inflammatory bowel disease when more traditional medications are ineffective. The decision to use these medications includes assessing risk factors.
5) Which of the following would be a contraindication to starting a TNFi?
Last updated February 2015