Learning Radiology xray montage

Rheumatoid Lung

  • Although rheumatoid arthritis is more common in females, extra-articular manifestations of the disease are more common in males

  • Almost all patients with pulmonary evidence of RA have:

    • Clinical evidence of the disease

    • Severe disease

  • Circulating antibody is largely IgM in patients with RA and the changes in the lung are probably immune in origin

Pleural Effusion  

  • The most common manifestation of RA in the chest

  • Pleural fluid is an exudate with a high protein and a very low sugar content (below 30 mg per 100 ml) which does not rise with the IV administration of glucose which the low sugar effusion in TB will do.

  • Pleural fluid in RA is also high in LDH, rich in lymphocytes, positive for Rheumatoid Factor, and contains low complement levels.

  • The effusion may remain unchanged for months or years

  • Most are unilateral but they can occur on either side

  • The effusion is almost never associated with parenchymal disease

Pulmonary Fibrosis  

  • Begins as micronodular and progresses to coarse reticulation, often more prominent at the bases and indistinguishable from scleroderma

    • Has a honeycomb appearance

  • Clinically, shortness of breath is most common symptom

  • Subcutaneous rheumatoid nodules are often present

  • PFTs show restrictive disease

Necrobiotic Nodules  

  • Relatively rare

  • Almost always associated with subcutaneous nodules and identical pathologically to them

    • Usually well circumscribed masses

    • Typically multiple

    • Subpleural in location

    • With cavitation

    • Frequently at bases

Caplan’s Syndrome  

  • Necrobiotic nodules with silicosis

  • Pathologically, the only difference is a ring of dust in the nodule which produces a darkened ring around the central core

  • Roentgenographically identical to rheumatoid nodules with RA

Rheumatoid Disease with Pulmonary Arterial Hypertension  

  • Due to an arteritis which produces PAH and eventual cor pulmonale

Obliterative Bronchiolitis  

  • Same as BOOP except the patients have RA