From the Guidelines
Trypsin activity is most likely impaired in this patient. The absence of enteropeptidase in the proximal intestinal villi directly affects trypsin activation, as enteropeptidase is responsible for converting trypsinogen to trypsin 1. This conversion is crucial for protein digestion, and without it, trypsinogen remains inactive, leading to impaired protein digestion. The patient's symptoms of large-volume diarrhea and failure to thrive can be explained by the malabsorption of proteins, which cannot be properly broken down and absorbed due to the lack of trypsin activity. Key points to consider in this case include:
- The role of enteropeptidase in activating trypsinogen to trypsin
- The importance of trypsin in protein digestion
- The consequences of impaired trypsin activity, including malabsorption and the patient's symptoms. Given the information provided and the underlying biochemical processes, trypsin is the substance whose activity would be most significantly affected in this case, as its activation is directly dependent on the presence and activity of enteropeptidase 1.
From the Research
Impaired Substance Activity
The patient's symptoms, including large-volume diarrhea and failure to thrive, along with the absence of enteropeptidase activity in the proximal intestinal villi, suggest an impairment in the activation of pancreatic proteolytic enzymes.
- The substance most likely impaired in this patient is trypsin, as enteropeptidase plays a key role in activating trypsinogen to trypsin in the small intestine 2.
- Trypsin is essential for the activation of other pancreatic zymogens, and its impaired activity can lead to a severe disturbance of protein digestion, resulting in symptoms such as failure to thrive, hypoproteinemia, and anemia 2.
- The activation of trypsinogen to trypsin is a critical step in the digestive process, and enteropeptidase is the primary enzyme responsible for this activation in the human small intestine 2, 3, 4, 5.