Key Clinical Questions
What are the signs and symptoms of cervical spine involvement in rheumatoid arthritis and the spondyloarthritides?
What tests should be ordered in patients with suspected pulmonary-renal syndrome?
Which patients with interstitial lung disease are most likely to respond to corticosteroids?
What are common and uncommon clinical signs and symptoms associated with giant cell arteritis?
What factors portend an impending renal crisis in a patient with known scleroderma?
What are the risk factors for Raynaud digital crisis? What treatments reduce morbidity?
Rheumatologic diseases rarely present as an acute emergency. However, when they do, a delay in diagnosis can lead to significant morbidity and mortality. The most important and common examples of this include: (1) cervical spine involvement in inflammatory arthritides; (2) recognition of the protean presentations of giant cell arteritis so as to prevent permanent visual loss; (3) early diagnosis of pulmonary-renal syndromes which, if unrecognized, can lead to life-threatening respiratory failure and renal failure; and (4) scleroderma renal crisis, in which a delay in diagnosis can mean the missing of the therapeutic window in which renal function can be rescued. In each of these conditions, involvement of a rheumatologist is often warranted.
THE CERVICAL SPINE IN THE RHEUMATIC DISEASES
Catastrophic neurologic injury and even death may result from cervical spine disease in patients with rheumatoid arthritis (RA) or spondyloarthritis (SPA). Early recognition of the signs and symptoms and appropriate diagnostic evaluation are critical to avoid these complications.
Up to 30% of patients with severe RA have some degree of subluxation of the atlantoaxial joint (C1-C2). In normal patients, the odontoid process of the axis (C2) is secured in front by the anterior arch of the atlas (C1), and posteriorly by the transverse ligament of the atlas. The normal distance between the odontoid process and the anterior arch of the atlas is 3 mm. Inflammation in the small joints that make up the atlantoaxial joint, or tenosynovitis of the transverse ligament of the axis, may weaken the transverse ligament, as well as lead to bony erosions in the odontoid process. As a result, the space between the odontoid and the anterior arch of the atlas widens (Figure 246-1), and the atlantoaxial joint becomes unstable. Anterior subluxation, in which the atlas slides forward relative to the axis, is the most common type of cervical spine emergency. It leads to cord compression and cervical myelopathy. Less commonly, posterior subluxation occurs when the odontoid is badly damaged or fractured. Rarely, vertical C1-C2 subluxation occurs, with atlanto-axial impaction, migration of the odontoid into the foramen magnum, brainstem compression, and death. Atlantoaxial instability may also produce vertebrobasilar insufficiency by impairing blood flow in the vertebral arteries, which travel through the transverse foramina of the cervical spine.
Cervical spine in rheumatoid arthritis, showing atlantoaxial subluxation. A lateral view ...