A 26-Year-Old With Fever and Malaise Now Can't Tie His Shoes

Jeremy J. Logan, MD; Gautam Dehadrai, MD;  Herbert S Diamond, MD


September 09, 2021

Objective but low-sensitivity tests to quantify restriction of motion include touching the toes, the Schober test, and measurement of chest expansion.

Physical examination findings shortly after disease onset may include tenderness over the sacroiliac joints and spinous processes. Early in disease, limitation of spine motion is usually due to pain and tends to begin in the sacroiliac joints and lumbar spine and extend to the thoracic spine, rib cage, and cervical spine with disease progression. Fixed limitation of motion occurs as bony fusion progresses, with ankylosis of the annulus fibrosis and paravertebral ligaments. Peripheral joint examination may disclose large joint arthritis and tenderness over entheses.

Evidence of nonarticular involvement should also be considered during the physical examination. Eye involvement, including iritis, uveitis, and conjunctivitis, is the most common. Although uncommon, aortic insufficiency and conduction disturbances may be seen. Inflammatory bowel disease incidence is greatly increased. Other uncommon complications include cardiomyopathy, pericarditis, apical fibrosis of the lungs, bronchiectasis, and cavitation of the chest. A restrictive ventilatory pattern due to costovertebral joint involvement may be seen.

Diagnosis of ankylosing spondylitis is based on the findings of inflammatory arthritis of the sacroiliac joint and spine pain plus radiologic evidence of sacroiliitis. Classification criteria for ankylosing spondylitis include the Rome criteria (developed in 1963) and the New York criteria (developed in 1968). These are primarily intended for standardization of research studies and should not be used as the sole criteria for diagnosis. Clinical and radiologic features of seronegative spondyloarthropathies, including psoriatic arthritis, reactive arthritis, and arthritis associated with inflammatory bowel disease may include sacroiliitis and present challenges in differential diagnosis. Hyperparathyroidism and osteitis condensans ilii may also result in bilateral symmetric sacroiliac joint disease and should be considered in the differential diagnosis. Radiographically, diffuse idiopathic skeletal hyperostosis (DISH) DISH) typically occurs at a later age, produces wide-flowing calcification along discs, and does not produce erosion or fusion of sacroiliac joints.[1,2]

The earliest radiographic examination findings in the sacroiliac joints include erosions and increased bone density indicating inflammatory changes. This is followed by development of bone proliferation and ultimately, fusion of the joints. Findings are usually bilaterally symmetrical. In the spine, squaring of vertebral bodies is seen early, followed by calcification of the annulus fibrosis, which can progress to fusion of vertebrae and ultimately the radiologic appearance of a “bamboo” spine. Radiographically evident peripheral-joint abnormalities are seen in more than 50% of patients and often affect the symphysis pubis, manubriosternal, sternoclavicular, and other large central joints.[2,3]

Laboratory findings are of limited value. An elevated erythrocyte sedimentation rate or C-reactive protein level may occur with acute inflammation. The HLA-B27 histocompatibility antigen is found in more than 90% of White persons but also in 8% of healthy controls. A positive test result is less frequent in other groups. The test should not be relied on for diagnosis. Test results for rheumatoid factor are negative.


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