The pancreas in cystic fibrosis: chemical composition and comparative morphology.

Sections of pancreas from 16 individuals who died with cystic fibrosis (CF) 
were classified by morphometric criteria into four categories in increasing order 
of pancreatic involvement. The concentration of acini, islets, main ducts, lobular 
ducts, connective tissue, and fat was compared with control levels. The 
results show that in the least involved pancreases, from neonates who 
died under 5 months of age, acini were reduced to 33% 
of control levels and the following were increased: islets, to 410%, 
lobular ducts, to 250%; and main ducts, to 1700% of controls. 
With increasing severity of the pancreatic disease the acini were further 
reduced to 5% and lobular ducts to 37% of control levels, 
respectively. Main ducts increased by 19-fold, and fatty infiltration accounted for 
more than 25% of the fresh weight of the pancreas in 
9 of the 16 specimens. Comparative biochemical studies of 35 fibrocystic 
pancreases were quantitatively related to the severity of the pancreatic involvement 
as follows. Water and volatile matter, normally accounting for 80 +/-% 
of the weight of the fresh pancreas, was reduced to less 
than 30% in the most affected organs. The concentration of zinc 
diminished from near normal mean levels of 193 mugZn/g dry pancreas 
to 10% of this amount in the severely involved pancreas. Elevated 
concentrations of calcium, amounting to over 10 times control level, were 
found in obstructed ductal structures. Calcium was depleted from pancreatic sections 
adjacent to the obstructions. The following biochemical indicators were significantly different 
in their mean levels in the 35 fibrocystic pancreases when compared 
with the 17 controls: (P less than or equal to 0.001) 
fat, water, zinc, calcium, copper, magnesium, potassium, and sodium (P less 
than or equal to 0.01). 