In a study of patients with severe asthma who had eosinophils in their sputum despite extensive antiasthma medication, investigators showed that a high dose of extra intramuscular corticosteroids resulted in almost complete disappearance of eosinophilic cells, led to decreased use of “rescue” medications, and helped improve patients’ lung function tests.
Eosinophils are a type of white blood cell that constitute from 1 to 3 percent of the total white cell count. When foreign substances or infectious cells enter the body, lymphocytes and neutrophils attract eosinophils which release toxic substances that can destroy abnormal cells. Eosinophils function in allergic responses and in helping resist some infections.
Writing in the second issue for September 2004 of the American Thoracic Society’s peer-reviewed American Journal of Respiratory and Critical Care Medicine, Elisabeth H. Bel, M.D., Ph.D., of the Department of Pulmonary Diseases, Leiden University Medical Center, Leiden, The Netherlands, along with four associates, studied 22 non-smoking outpatients with severe asthma in order to prove that patients with extensive eosinophilia, despite significant anti-inflammatory treatment, were sensitive to high dose injected corticosteroids. Of the 22 patients in the study, 11 received the steroids and 11 were given placebo over a 3-week period. All patients had sputum eosinophilia above the upper limit of normal. However, after treatment with the injected corticosteroids, sputum eosinophils returned to normal levels (from zero to 2 percent) in the 11 treated patients.