Secretory immunoglobulin A in serum of CF patients.

Increased sIgA values were found in CF patients in about 70 per cent (3 studies with 23, 43, 45 CF patients). With higher severity of CF disease (Shwachman score) we could observe higher sIgA levels. Postmortem histological findings and sIgA concentrations correlated well in 13 cases. Determinations of sIgA in serum could serve as parameter for hepatobiliary involvement in CF. Secretory immunoglobulin A (sIgA) is the predominant immunoglobulin of exocrine secretions. In serum large and frequent elevations of sIgA could be found in patients with chronic liver disease characterized by biliary obstruction (3). Slight and irregular elevations were observed in patients with disorders of gastrointestinal tract and of respiratory tract as well as in lactating women (3). Manifestations of the hepatobiliary system in CF will become more important with advancing age and progressively higher life expectancy of CF patients. A simple reliable test for detection of hepatobiliary involvement in CF would be useful.