Counterimmunoelectrophoresis of sputum and blood for the diagnosis of chest infections caused by pneumococci or Haemophilus influenzae.

In 107 patients with lower respiratory tract infections, counterimmunoelectrophoresis (CIE) of blood and sputum, bacterial cultures of blood, sputum and nasopharyngeal secretion, and enzyme-linked immunosorbent assay (ELISA) for antibody determination were performed, with special reference to pneumococci and Haemophilus influenzae. For pneumococci CIE of sputum was superior to culture especially in antibiotic-treated patients. The clinical significance of a positive CIE of sputum was supported by close correlation to significant antibody increase. The usefulness of CIE regarding H. influenzae was more difficult to evaluate.