Enterokinase deficiency

Congenital deficiency of this small intestine enzyme has been reported in a few children, resulting in the complete absence of pancreatic proteolytic activity; enterokinase is an essential activator of pancreatic trypsinogens.

The presentation is of infants that are ill from very early in life with severe diarrhoea and failure to thrive. Hypoproteinaemia is common in this condition and this may cause oedema. The tryptic activity in duodenal juice is missing while lipase and amylase are normal. In vitro the activity of the juice can be restored by the addition of enterokinase. The major result of this condition is malabsorption of protein although steatorrhoea has been reported.

The supplementation of the diet with pancreatic enzyme replacements restores normal digestive function.