Gastroenterology

Pathophysiology and Clinical Applications

Harvey J. Dworken

• Publisher: Butterworth-Heinemann
• Year: 2014
• Print ISBN: 9780409950212
• eBook ISBN: 9781483192673
• Topic: Medicine
• Subtopic: Diseases & Allergies

Gastroenterology is based on its predecessor volume ""The Alimentary Tract"" but the content has been rewritten almost completely. The scope has been expanded to account for major developments in the field of gastroenterology and in order to make the volume more useful to house officers and practicing physicians. The text is designed to be read first, and then summarized if desired with illustrated lectures and demonstrations. This book is organized into 20 chapters. These chapters cover updated gastroenterological topics as of 1982 including symptoms, diagnosis and treatment of diverticular diseases of the colon and lower small intestine; the incidence and distribution of inflammatory bowel diseases; and classification and pathological mechanism of diarrheal disorders. This book will of interest to house officers and practicing physicians.

Chapter 1

History Taking in Gastrointestinal Disease, and Evaluation of Abdominal Pain

Publisher Summary

This chapter presents an orderly approach for evaluating pain appearing in any quadrant of the abdomen. The approach requires an adequate knowledge of the major disorders that may occur in the abdomen, their usual presenting and associated symptoms, and the physical findings that may be anticipated. Each diagnostic procedures should be employed to answer a specific question, and those that are least costly and least troublesome for the patient should be used first. The willy-nilly use of any and all diagnostic procedures tends to add much to the patient’s discomfort and little to the solution of the clinical problem. The physician of the 1980s is at considerable risk of suffering from an abundance of riches when the full range of diagnostic procedures currently available is critically analyzed. Not only have conventional radiological procedures been improved but also entirely new techniques such as ultrasonography and computed tomographic scanning have been shown to be capable of duplicating, supplementing, or even replacing the older modalities.

In this book we intend to undertake a thorough examination of the digestive tract, its diseases and their treatment, and to delineate their pathophysiology to the extent that that is possible in these waning years of the twentieth century. At first, we focus briefly on the individual patient with a digestive disorder, with the aim of developing a logical approach to the diagnosis of our patient’s problem in the most direct fashion and with the least discomfort and expense. We commence by suggesting an approach to history taking, and follow with a plan for evaluating abdominal pain by both physical diagnosis and by ancillary diagnostic procedures which will be described more fully later.

HISTORY TAKING

Derangements of normal physiology eventually approach the level of perception and manifest themselves to patients as symptoms. All too often, such symptoms do not appear until disease has become well established, and even then they might be nonspecific and may define the disease process imperfectly. Despite this inexactitude, a careful physician can often delineate the progress of a disorder and deduce the mechanisms involved. Success in these efforts is limited by the experience of the physician, the adequacy of the approach to the patient, and by the patient’s own ability to describe the difficulty intelligibly. Taking the time to talk with patients and caring enough to employ an orderly and complete approach often makes the task more simple. Gastrointestinal complaints can be grouped under a number of headings, each of which should be investigated thoroughly. It is the purpose of this section to suggest such an approach.

Pain

Type.

Cramplike pain usually suggests hyperperistalsis of the type associated with inflammation or obstruction of the small intestine or colon. It is also encountered frequently with psychogenic or functional alimentary disorders. A steady pain suggests a localized disorder. Sharp pains are most often due to spasm of intestinal musculature or acute inflammation of the viscera or peritoneum, whereas dull pains suggest visceral distention associated with partial obstruction or chronic inflammation. Patients with peptic ulcer or esophagitis often describe their discomfort as burning.

Severity.

The patient’s own description of the discomfort is extremely helpful, even when one discounts for hyperbole. The pain of acute peritonitis is often so excruciating that the patient cannot tolerate movement of the abdomen, or even deep breathing, as in acute pancreatitis or perforated peptic ulcer. Such pain is usually sudden in onset, though it may have been preceded by less intense pain for hours or days. The pain of an inflamed gall bladder or appendix progresses more slowly and usually does not reach such extreme intensities. Cancer may be painless until it causes visceral obstruction or spreads to surrounding tissues. Under this circumstance, pain gradually becomes more severe, prolonged, and relentless.

Location.

Location is a very important determinant, the general location of pain often suggesting the organ involved. Biliary tract, pancreatic, and duodenal disorders commonly produce pain in the right upper abdomen; cecal, appendiceal, and lower ileal diseases, in the right lower section; and descending colonic or sigmoidal disorders, in the left lower abdomen. Supra-umbilical pain relates mainly to organs above the jejunum, including gall bladder, liver, pancreas, duodenum, and stomach. Usually, the more sharply localized the pain, the more likely is the parietal peritoneum to be involved. Infraumbilical pain suggests small intestinal or colonic disorders. Vague, diffuse lower abdominal discomfort often accompanies inflammatory or psychogenic intestinal disease. One must always be mindful of the fact that not all abdominal pain stems from the alimentary tract—primary diseases of the urogenital system and the large abdominal arteries also cause abdominal pain!

Radiation.

Patterns of pain radiation often suggest disease loci. Thus, right upper abdominal pain which radiates posteriorly and upward to a point between the shoulder blades suggests inflammation in the gall bladder or biliary tree. Pain in a similar part of the abdomen referred as well to the right scapuloclavicular junction suggests inflammation of the diaphragm, such as occurs with a subphrenic abscess. The pain of a penetrating peptic ulcer or of retroperitoneal disorders such as pancreatitis, cancer of the pancreas, or aneurysms of the abdominal aorta are often most severe in lower dorsal or upper lumbar levels of the back. A psoas abscess may produce pain that radiates downward into the groin and thigh.

Relationships.

Knowledge of what relieves or aggravates pain is frequently a helpful indication of disease. Immediate aggravation by meals suggests that the disease somehow interferes with normal postprandial hyperperistaltic reflexes, a situation encountered in partial intestinal obstructions, intestinal inflammations, or in psychogenic disorders. Pain that appears some hours after a large meal suggests interference with normal gall bladder emptying or pancreatic secretion, as in cholelithiasis or pancreatitis. The pain of peptic ulcer or esophagitis is often promptly relieved by eating, whereas the patient with alcoholic gastritis may experience partial, transient relief from a drink of spirits.

Vomiting often relieves the pain of gastric retention or intestinal obstruction, whereas it usually does not affect, or worsens, symptoms of cholecystitis or pancreatitis. Passage of stool or flatus commonly improves the discomfort of inflammatory or obstructive lower bowel disorders.

Borborygmi (audible bowel sounds) related to abdominal cramps suggest the sort of hyperperistalsis that may accompany obstructive or inflammatory disease or some disorders or intestinal motility, such as the irritable bowel syndrome. A previous history of abdominal surgery might implicate postoperative adhesions as a cause of the obstruction. Chills and fever with abdominal pain suggest abscess formation or extensive inflammation. A recent abdominal injury prior to the onset of pain draws one’s attention to the possibility of intra-abdominal hemorrhage or visceral perforation.

Anorexia and Weight Loss

Many patients are endowed with very frail appetites, and anorexia in such individuals may accompany any feeling of unease and be of little diagnostic value. However, significant and documentable loss of weight is always an important symptom, whether accompanied by anorexia or not.

Anorexia associated with fever suggests inflammatory disease or abscess. The resultant loss of weight is caused by both decreased caloric intake and increased metabolic demands. Malignant neoplasms also lead to prodigious losses of weight because of the increased metabolic requirements of the malignant tissue. Anorexia may also be caused by certain drugs, such as digitalis, or by a fear of the patient that eating will aggravate the abdominal pain.

In patients in whom weight falls despite a good or increased appetite, one must think of hypermetabolic states, such as hyperthyroidism, or conditions wherein normal metabolic pathways are interrupted by disease, such as uncontrolled diabetes mellitus, or disorders of intestinal absorption. Food faddists, such as vegetarians, commonly lose weight because of simple caloric inadequacy and protein malnutrition. More tragic cases of weight loss despite a good appetite exist in our society among those persons who are either too poor or too old, or both, to obtain the food necessary to maintain nutritional parity. Misdirected appetites for alcohol or drugs also frequently lead to weight loss stemming from caloric inadequacy.

Regurgitation and Heartburn (Pyrosis)

Regurgitation is a passive symptom in which esophageal, gastric or duodenal contents appear in the mouth without being preceded by retching or vomiting. If the contents merely taste like previously swallowed material, the chances are good that they have never entered the stomach and are regurgitated because they were sequestered in a diverticulum or were unable to traverse the full length of the esophagus because of obstruction or muscular dysfunction of that organ.

Regurgitation of sour and partially digested contents suggests that the reflux arose in the stomach and passed too readily retrograde into the esophagus. This symptom implies decreased competence of the sphincteric mechanism at the lower end of the esophagus, and the possible presence of a hiatal hernia. Bitter regurgitant fluid, particularly if it is bile stained, represents reflux of duodenal contents. This is encountered commonly in patients with previous partial gastric resections who also suffer from decreased competence of the gastroesophageal sphincter, and in many patients with gastritis or gastric ulcer.

Heartburn is a burning distress usually felt beneath the sternum, and commonly aggravated by large meals and by lying down. It results from irritation of the esophageal mucosa by acid or bilious gastric contents, and its occurrence correlates well with gross or microscopic findings of esophagitis in the lower esophagus. Assuming a recumbent position facilitates flow from stomach to esophagus and aggravates heartburn. Ingestion of antacids generally brings prompt relief.

Dysphagia

The patient who complains of difficulty in swallowing almost invariably has a disorder that can be precisely diagnosed. Dysphagia should be clearly distinguished by history from the feeling of a lump in the throat that does not interfere with swallowing and is usually psychogenic in origin.

Most disorders compromising the lumen of the esophagus (e.g., stricture, cancer or an obtruding mediastinal mass) gradually lead to a progressive form of swallowing difficulty, wherein the patient first experiences trouble with solid, then with liquid foods. Achalasia is the outstanding exception, patients usually experiencing equal difficulty from the start with solids and liquids, or even having more trouble with the latter.

Relationships.

A history of heavy smoking in a patient with dysphagia makes one suspect a carcinoma of the esophagus. Nasogastric intubation in the recent past or a history of ingestion of caustic agents favors a diagnosis of stricture of the esophagus. Raynaud phenomenon or thickening of the skin is often found with scleroderma of the esophagus. Although loss of weight occurs with almost all forms of dysphagia, its absence favors a diagnosis of diffuse esophageal spasm. Previous heartburn or sour regurgitation suggests that dysphagia results from esophagitis and stricture, whereas pain with dysphagia (odynophagia) supports the impression of an esophageal ulcer, ulcerated neoplasm, or Candida or herpetic esophagitis.

Nausea and Vomiting

As an isolated symptom, nausea is often functional in origin, commonly accompanying the constipation and flatulence frequently associated with the irritable colon syndrome. However, since nausea may also be an early sign of disorders, such as digitalis intoxication, pregnancy, or hepatitis, its significance should never be minimized without fuller investigation. A careful history of drug ingestion, disease exposure, and menstrual activity should be obtained. Nausea, especially in the morning, may be an early symptom of alcohol withdrawal. Its relief by a drink of spirits is diagnostic.

A single episode of vomiting, while especially significant in an adult, might merely be an accompaniment to an infection or fever and have no specific import in relation to alimentary disease. Repeated vomiting, however, is another matter, and is often critically important.

Type of vomiting.

Repeated vomiting of recently ingested gastric contents is commonly encountered in gastritis, peptic ulcer, alcoholism, and pancreatitis, and is occasionally seen in certain types of drug intoxication (e.g., digitalis) or in metabolic disorders, such as uremia.

Retention vomiting is usually the result of obstructions from ulcer or neoplasm. It is typified by vomitus, usually voluminous, containing food eaten many hours or several days before. The absence of bile staining indicates that duodenal contents are not able to reflux into the stomach.

Hematemesis implies that bleeding has arisen from above the ligament of Treitz (duodenal-jejunal junction). Coffee-grounds vomitus has the same significance, but indicates that blood has been in contact with acid gastric contents long enough to convert hemoglobin to acid hematin. Vo...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• Dedication
• Preface
• Acknowledgments
• Chapter 1: History Taking in Gastrointestinal Disease, and Evaluation of Abdominal Pain
• Chapter 2: A Survey of Gastrointestinal Hormonology
• Chapter 3: The Esophagus
• Chapter 4: Functional Characteristics of the Stomach
• Chapter 5: Gastritis and Gastric Mucosal Hypertrophy
• Chapter 6: The Pathophysiology of Peptic Ulcer
• Chapter 7: The Liver: Structure and Function
• Chapter 8: Mechanisms and Diagnosis of Hepatic Disease
• Chapter 9: Complications of Advanced Liver Disease
• Chapter 10: Agents Causing Acute Hepatitis
• Chapter 11: Singular Forms of Cirrhosis of the Liver
• Chapter 12: The Biliary Tract
• Chapter 13: The Pancreas: Physiology, Inflammations, and Neoplasms
• Chapter 14: The Small Intestine and Colon: Structure and Function
• Chapter 15: Disorders of Intestinal Absorption
• Chapter 16: Diarrhea and Constipation: Mechanisms, Classification, and Illustrations
• Chapter 17: Inflammatory Bowel Disease
• Chapter 18: Mesenteric Vascular and Angiodysplastic Disorders
• Chapter 19: Diverticular Diseases of the Colon and Lower Small Intestine
• Chapter 20: Polyps and Cancer of the Colon
• Clinical Conference Discussions
• INDEX