A young boy presents with failure to thrive. Biochemical analysis of a aspirate after a meal reveals a deficiency of enteropeptidase (enterokinase). The levels of which digestive enzymes would be affected?
**Core Concept**
The underlying principle being tested is the role of **enteropeptidase (enterokinase)** in the activation of pancreatic digestive enzymes. Enteropeptidase is an enzyme produced by the cells of the duodenum that plays a crucial role in the activation of trypsinogen to trypsin. **Trypsin** then activates other pancreatic enzymes.
**Why the Correct Answer is Right**
The correct answer is related to the enzymes that are directly or indirectly activated by trypsin. Trypsin activates **chymotrypsinogen** to chymotrypsin, **procarboxypeptidase** to carboxypeptidase, and other enzymes. Thus, a deficiency in enteropeptidase would lead to reduced activation of these enzymes, affecting their levels and activity.
**Why Each Wrong Option is Incorrect**
**Option A:** This option might be incorrect because it does not directly relate to the primary action of enteropeptidase.
**Option B:** Similarly, this option might not be directly related to the enzymes activated by trypsin.
**Option D:** This option is incorrect because it does not accurately reflect the enzymes whose levels would be affected by a deficiency in enteropeptidase.
**Clinical Pearl / High-Yield Fact**
A key point to remember is that enteropeptidase deficiency can lead to malabsorption and failure to thrive due to the impaired activation of pancreatic enzymes. This condition highlights the importance of **enteropeptidase** in digestive processes.
**Correct Answer:** D. Trypsin, chymotrypsin, and carboxypeptidase