IgG subclass deficiency associated with corticosteroids in obstructive lung disease.

IgG subclass levels were measured in three groups of adult patients with obstructive airways disease to discern the relationships among depressed IgG subclass levels, chronic corticosteroid use, and recurrent sinopulmonary infections. Group 1 consisted of patients with corticosteroid-dependent bronchial asthma, group 2 patients had corticosteroid-dependent chronic bronchitis/emphysema, and group 3 was comprised of asthma patients not requiring oral corticosteroids but associated with recurrent sinopulmonary infections. One or more IgG subclass deficiencies were noted in 66.7 percent of group 1, 46.7 percent of group 2, and 6.7 percent of group 3. Significant differences were noted between groups 1 and 3 (p = .0008) and between groups 2 and 3 (p = .018), but not between groups 1 and 2 (p = .5). IgG1 deficiency was the most common subclass deficiency found; 14 (77.8 percent) of 18 patients with detectable subclass deficiency demonstrated IgG1 deficiency. In this study population, IgG subclass level deficiencies appeared to be secondary to long-term low-dose corticosteroid therapy.

Enalapril induced angioedema.

A report of three patients who developed angiodema while receiving enalapril. Patient 1 came in with an 8-hour history of facial swelling after enalapril had been started 2 days earlier. The second patient came in with severe angiodema of the tongue, larynx, and glottis requiring emergency tracheostomy, hydroxyzine, and steroids. He had been treated with enalapril for 1 year. The third patient developed facial swelling within a few hours of the first dose of enalapril. Angiodema with enalapril can occur early or late in the course of therapy. A possible mechanism for this drug reaction is the potentiation of bradykinin with resultant kinin system activation.

Quantitative immunoglobulins and IgG subclasses in patients with corticosteroid-dependent reversible airway obstruction.

Six of 12 patients with corticosteroid-dependent bronchial asthma and recurrent sinopulmonary infections were found to have significant abnormalities in quantitative immunoglobulins and/or IgG subclasses. Five patients had a combined quantitative immunoglobulin and IgG subclass deficiency and one patient had an isolated IgG deficiency. Combined IgG subclass deficiencies were observed in two patients, both with deficiencies of IgG2 and IgG3. The most common IgG subclass deficiencies were of IgG2 and IgG3, which were found in three patients each.