Alterations in immunoglobulin & complement levels in chronic obstructive pulmonary disease

Thirty patients of chronic obstructive pulmonary disease (COPD; all smokers) and an equal number of controls (15 smokers) were studied. The COPD patients were further divided into group A (predominantly emphysema) and group B (predominantly bronchitis) of 15 patients each. Serum and sputum IgG, IgA and IgM and serum C3 and C4 were estimated. IgG, IgA, IgM and C3 and C4 were similar in smoker and non-smoker controls. Mean (+/- SD) serum IgG (IU/ml) was significantly higher in COPD patients (207.78 +/- 62.73) than in control (177.25 +/- 43.5; P less than 0.05), serum IgA (IU/ml) was also significantly higher in COPD (205.04 +/- 46.56) than in control (108.21 +/- 33.3; P less than 0.01). IgM was similar in the 2 groups. Sputum IgA (IU/ml) was higher in COPD (4.68 +/- 3.51) than in control (2.25 +/- 1.03; P less than 0.05). IgG and IgM were similar in the 2 groups. Both serum C3 (IU) and C4 (IU) were lower in COPD patients (C3 = 95.9 +/- 33.11, C4 = 113.6 +/- 62.4) than in control (C3 = 167.3 +/- 25.42, C4 = 205 +/- 76.5; P less than 0.05). Serum IgA in type B COPD (212.25 +/- 50.06) was higher than in type A (197.52 +/- 43.3; P less than 0.05) IgG and IgM were similar in these 2 groups. In COPD patients, immunoglobulins were either normal or higher indicating that deficiency of immunoglobulin is not a predisposing factor in development of COPD. Similar immunoglobulin values in smoker and nonsmoker controls indicated that smoking was not the cause of rise of immunoglobulins in COPD.(ABSTRACT TRUNCATED AT 250 WORDS)