Glands may Become obstructed by viscid or solid eosinophilic material in the lumen (pancreas, intestinal glands, intrahepatic bile ducts, gallbladder, and submaxillary glands) Appear histologically abnormal and produce excessive secretions (tracheobronchial and Brunner glands) Appear histologically normal but secrete excessive sodium and chloride (sweat, parotid, and small salivary glands) Respiratory Although the lungs are generally histologically normal at birth, most patients develop pulmonary disease beginning in infancy or early childhood.