Question

It’s Friday morning and Sal Volpe is sitting in Dr. Lorraine’s exam room, dozing after another night of disrupted sleep. When the doctor knocks and walks in, she finds the 66-year-old man looking exhausted and uncomfortable. Sal gets to the reason for his visit immediately: He’s been suffering from “stomach aches” (dyspepsia) that wake him at night and nag him in between meals during the day. He describes his pain as gnawing, burning (maybe a 4 out of 10 on a pain scale) and points to the epigastric region of his abdomen. When he eats, he tells Dr. Lorraine, the pain goes away, but then he feels bloated and a little nauseated. The pain usually returns 2–4 hours later, depending on what he eats. Sal explains that he has had some pain relief from the over-the-counter drug Pepcid^® (famotadine).

Dr. Lorraine proceeds with the history and physical exam. She discovers that Sal has a family history for gastrointestinal cancer and has unintentionally lost 10 pounds since his checkup a year ago. His epigastric area is modestly tender to palpation. She suspects a peptic ulcer (gastric or duodenal), but the weight loss and family history make it prudent to eliminate the diagnosis of stomach (gastric) cancer. “Mr. Volpe, I think you may have a stomach or intestinal ulcer,” Dr. Lorraine says. “I suggest we perform an endoscopy to have a look. This involves passing a small tube with a small camera through your mouth and into your stomach. We can look at the wall of your stomach and small intestine, check for an ulcer, and remove a very small piece of tissue to test for infection. We call this a biopsy. We’ll also test the biopsy for cancer because of your family history. But, I really think we’re dealing with an ulcer here and not cancer.”

Later that month, the endoscopy is performed and it confirms Dr. Lorraine’s suspicions. Sal has a duodenal ulcer and infection with the bacterium Helicobacter pylori (H. pylori). This is not surprising since H. pylori is the cause of most peptic ulcer disease, particularly in the duodenum. Treatment involves complete eradication of the H. pylori with two different antibiotics, and a drug that decreases gastric acid secretion, a so-called proton pump inhibitor (PPI). Dr. Lorraine explains to Sal, “Mr. Volpe, you do not have stomach cancer, but you do have a duodenal ulcer caused by the H. pylori bacteria I was telling you about. Too much acid and inflammation from this infection is causing your pain. The good news is we can probably cure your ulcer by killing the bacteria, but you will have to take three different medications twice a day for 14 days. I’ll see you again in 3 weeks; we can do a simple breath test to determine if the H. pylori has been successfully eliminated.”

Short Answer Questions:

1. The structures in the epigastric region share a common nerve supply. Can you name the specific cranial nerve that serves this region and the part of the nervous system to which it belongs?
2. In order to understand the disease in Mr. Volpe’s alimentary canal, one must know the layers that make up its walls. Design a chart that identifies the four basic layers of the alimentary canal, the tissues that make up each layer, and the general function of each layer.
3. Dr. Lorraine suspects a peptic ulcer. This is an inflammatory lesion in the stomach or duodenal mucosa, which may extend through all layers of the alimentary canal wall. Describe the basic histological (tissue) structure of the mucosa layer in the alimentary canal. Identify the unique features of the mucosa in the stomach and in the duodenum, and explain how this uniqueness determines the function of the stomach and the duodenum.
4. Mr. Volpe asks, “What do the bacteria have to do with the ulcer?” Dr. Lorraine tells him that the H. pylori increases stomach acid secretion and, at the same time, breaks down the lining of your stomach and duodenum. What is the source and normal function of acid in the stomach and what regulates its production
5. Why is Mr. Volpe’s dyspepsia relieved by food, and aggravated 2–4 hours after a meal?

Answer 1

Structures in epigastric areas include stomach , liver , part of duodenum. In this stomach is supplied by vagus nerve , the 10th cranial nerve . Its parasympathetic branch , supplies the walls of stomach and also walls of alimentary tract. It belongs to peripheral nervous system, specifically to parasympathetic branch of autonomic nervous system.

4 layers that makes up alimentary canal from inside to outside are , 1). Mucosa 2). Submucosa 3). Muscularis layer 4). Serosa .

Mucosa consists of columnar epithelium wich is responsible for secretion of mucous and other enzymes responsible for digestion. Below it is lamina propria which has digestive glands. Submucosa has connective tissue and blood vessels which supply nutrients. Muscularis is made of smooth muscles, which is responsible for contraction and peristaltic activity of the alimentary canal . Serosa is the outermost layer made of connective tissue, which holds the alimentary canal in position .

Mucosa of stomach is thrown into folds called rugae , it secretes hcl and pepsin from gastric glands which is involved in protein digestion . Mucosa of duodenum has finger like projections called villous which also secretes intestinal juice and involved in absorption of digested products . The villous has microvilli , which increases surface area for absorption.  

Stomach has parietal cells lining mucosa , wich secretes hcl. Pepsinogen is an inactive peptide secreted from chief cells of stomach, pepsinogen is converted to pepsin by the action of hcl. Mucosal erosion due to hcl is prevented by bicarbonate secretion from mucosal cells. Hcl also kills the infective microbes that entes the stomach through food . It's secretion is stimulated by parasympathetic fiber wich cause release of gastrin an hormone produced from G cells of stomach. Its secretion inhibited by somatostatin secreted from D cells of stomach and duodenum . This h.pylori increases gastrin secretion and can survive in low ph . When food enters stomach the pyloric sphincters are closed and digestion takes place for about 2 to 4 hours , after this the food enters duodenum which cause pain . This type is specific in duodenal ulcer , where patient feels dyspepsia due to hunger because of duodenal secreted and relieved after food and aggravated 2 to 4 hrs after food .