Diseases of the Respiratory System - Sarcoidosis
Sarcoidosis (or Boeck's sarcoid ), a disease that affects black people more often than whites, has symptoms closely resembling those of tuberculosis and other diseases. The most obvious symptom is the formation of skin nodules, often of the face, but the nodules, called granulomas (small tumors composed chiefly of granulation tissue), commonly occur in many other places as well, especially in the lungs and lymph nodes. They can occur also in the liver, bones, eyes, and other tissues.
Although sarcoidosis occurs all over the world, it is more common in temperate regions. Men and women are about equally affected. The onset of the disease occurs usually in the third or fourth decade of life.
Diagnosis and Treatment
The disease is diagnosed by an examination of chest X rays, which will show the proliferation of nodules in the lungs. Surgical biopsy and microscopic examination of skin tissue or tissue from a lymph node is usually necessary to confirm the presence of the disease.
There is no specific treatment for sarcoidosis, and in spite of its similarities in some respects to tuberculosis, no connection between the two disorders has been established. Steroids are sometimes used to treat the skin lesions, but in many cases the skin nodules clear up eventually without any treatment. About half of the patients, however, do not recover completely, and the disease becomes chronic—though of varying severity. Ultimately the granulomas can change into fibrous scars that may pose serious threats to the patient, depending upon where the scarring occurs. Respiratory distress, heart failure, and glaucoma, for example, can result from tissue changes in the lungs, heart, and eyes, respectively.