Question

The patient stated that she had been experiencing frequent diarrhea, and that the feces appeared to be oily. Why would someone with Zollinger-Ellison syndrome have frequent episodes of diarrhea? A. Decreased ability of the large intestine to absorb water and compact feces B. Increased parasympathetic stimulation C. Overproduction of motilin by M cells of the small intestine in conjunction with oversecretion of gastrin by G cells D. Malabsorption due to villi blunting

Short answer

D. Malabsorption due to villi blunting.

Step-by-step solution

Identify Zollinger-Ellison Syndrome Characteristics

Understand the symptoms and effects of Zollinger-Ellison syndrome. This condition involves gastrin-secreting tumors, leading to excessive gastric acid production.

Connect Symptoms to Options

Relate the frequent diarrhea and oily feces to the potential reasons given in the options, considering how increased gastric acid can affect digestion.

Analyze Each Option

A: Consider if the large intestine's ability to absorb water and compact feces would be affected by Zollinger-Ellison syndrome.B: Evaluate whether increased parasympathetic stimulation is directly related to Zollinger-Ellison syndrome.C: Assess if overproduction of motilin along with gastrin could lead to the observed symptoms.D: Examine if malabsorption due to villi blunting fits the condition caused by Zollinger-Ellison syndrome.

Choose the Best Explanation

Given that Zollinger-Ellison syndrome causes excessive gastric acid production, it leads to malabsorption of fats and nutrients, often resulting in diarrhea and oily stools, indicating villi blunting. Thus, D is the most plausible explanation.

Key concepts

gastric acid production

Zollinger-Ellison syndrome is characterized by tumors called gastrinomas. These tumors secrete large amounts of the hormone gastrin. This results in the stomach producing excessive amounts of gastric acid.
High levels of gastric acid can lead to various digestive issues, including ulcers and gastroesophageal reflux disease (GERD).
In the context of our problem, this excessive acid disrupts normal digestive processes. Gastric acid breaks down food in the stomach, but too much acid can overwhelm the intestines, disrupting nutrient absorption.

malabsorption

Malabsorption occurs when the intestines cannot absorb nutrients properly from food.
In Zollinger-Ellison syndrome, excessive gastric acid in the intestines affects their ability to function normally. The acid can damage the lining of the intestines and interfere with the enzymes needed to digest and absorb food.
This leads to nutrient deficiency, including fats, proteins, and vitamins.
A key indicator of malabsorption is steatorrhea, where the stool becomes oily and foul-smelling because unabsorbed fats are being excreted.

villi blunting

The surface of the small intestine is covered with tiny, finger-like structures called villi. These villi increase the surface area for absorption of nutrients.
When exposed to excessive gastric acid, villi can become damaged and flatten out, a process known as villi blunting.
This damage to the villi further impacts the intestine's ability to absorb nutrients, contributing to malabsorption.
Blunted villi are less effective at absorbing fats and other essential nutrients from digested food.

diarrhea

Diarrhea is a common symptom of malabsorption and villi blunting caused by Zollinger-Ellison syndrome.
When the intestines are damaged and not absorbing nutrients properly, food moves too quickly through the digestive system.
This rapid movement does not allow enough time for water to be absorbed, leading to watery stools.
Excess fat in the stool, due to malabsorption, makes it oily. Chronic diarrhea can lead to dehydration and further nutritional deficiencies.
Effective management of Zollinger-Ellison syndrome often includes medications to reduce stomach acid and dietary adjustments to support nutrient absorption.