Gastroenterology. Pathophysiology and Clinical Applications

653 Pages·1982·17.327 MB·English

by  Harvey J. Dworken (Auth.)

GASTROENTEROLOGY
PATHOPHYSIOLOGY AND
CLINICAL APPLICATIONS
Harvey J. Dworken, M.D.
Associate Professor in Medicine,
Case Western Reserve University;
Director, Division of Gastroenterology,
University Hospitals,
Cleveland, Ohio
BUTTERWORTHS
Boston · London
Copyright © 1982 by Butterworth (Publishers) Inc. All rights reserved.
No part of this publication may be reproduced, stored in a retrieval sys-
tem, or transmitted, in any form or by any means, electronic, mechanical,
photocopying, recording, or otherwise, without the prior written permis-
sion of the publisher.
Every effort has been made to ensure that the drug dosage schedules
within this text are accurate and conform to standards accepted at time
of publication. However, as treatment recommendations vary in light of
continuing research and clinical experience, the reader is advised to
verify drug dosage schedules herein with information found on product
information sheets. This is especially true in cases of new or infrequently
used drugs.
Butterworth Publishers Inc.
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Library of Congress Cataloging in Publication Data
Dworken, Harvey J.
Gastroenterology: pathophysiology and clinical applications.
Includes bibliographies and index.
1. Gastrointestinal system —Diseases. 2. Gastroenterology. I. Title.
[DNLM. 1. Gastrointestinal diseases. Wl 100 D993g]
RC801.D94 616.33 81-10223
ISBN 0-409-95201-1 AACR2
Printed in the United States of America
To NKD,
Your patience, support, forbearance and
affection were essential ingredients.
Preface
While the objectives of this work remain essentially unchanged from those
of its predecessor volume, The Alimentary Tract, usage of the original ver-
sion has suggested a number of conceptual alterations. The text has been
rewritten almost completely, and summarizes much of the mass of new infor-
mation which has become available during the past seven years. The scope
has also been increased greatly in order to make the book more useful to
house officers and to practising physicians. The bibliography has been ex-
panded and, since there is much to be learned from past medical experi-
ences, brief historical notes have been added liberally throughout the text,
usually at the ends of chapters. The rule for these is that no eponymic terms
be applied without there being at least a laconic notation of the persons in-
volved, their dates, their fields and locations of work, and their patrimony.
One thus learns quickly that the edifice of modern gastroenterology stands
on a foundation which owes no particular allegiance to any one place or any
one time. The major thrust of the work remains unchanged. The text is de-
signed to be read first, and then summarized if desired with illustrated lec-
tures and demonstrations. Content may then be firmly fixed in memory by
discussion in small groups of the problems and clinical conferences placed
at the end of each chapter.
Though it may appear to be an act of hubris for a single author to at-
tempt to write a complete text on alimentary disease in these days of bur-
geoning research and increasing specialization, it is my hope that certain
advantages may be realized. Among these are a fairly uniform approach to
the material with a minimum of unplanned repetition, treatment of each
topic which is less detailed than in a work by subspecialists but which is
nonetheless broad enough in scope to fill the needs of students and physi-
cians, and the opportunity to inject the personal reactions of a single phy-
sician who has had the good fortune to live through a period of great change
in his field of major professional interest. The text itself, while indubitably
greater in length and breadth than its predecessor, will certainly weigh less
heavily than multiauthored books and should, with luck, be readable
through with a minimal amount of literary sedation.
Throughout the book, I have striven to achieve a logical development of
each topic, citing appropriate references, and indicating where more infor-
xviii
mation is needed, all with the interests of the readers and their patients
clearly in mind. Should it succeed, the mighty effort required will have been
worth the while.
Harvey /. Dwarken
Cleveland, 1981
Acknowledgments
Many friends and colleagues have helped me during the course of my re-
search and writing of this text. I owe great thanks to Case Western Reserve
University and to Dr. Charles C.J. Carpenter, Chairman of the Department of
Medicine, for granting me a sabbatical leave of six months to get this project
under way. The entire staff of the Allen Memorial Library, Cleveland, was
inordinately helpful and patient in providing me with an office and in com-
plying with many requests, large and small. Most supportive were Lydia
Holian, Associate Librarian, and Glen Jenkins of the Howard Dittrick Mu-
seum of Historical Medicine. For reading portions of the text and offering
useful suggestions, thanks should go to colleagues Donald D. Anthony, James
M. Boyle, Lansing C. Hoskins, John B. Marshall, Mary Petrelli, and Anthony
S. Tavill, as well as to two anonymous referees solicited by my publishers,
and to many students. Dr. Yao Shi Fu, of the Department of Pathology, de-
serves double recognition for both his editorial guidance and his prepara-
tion of the numerous photomicrographs which illustrate this volume. Typing
chores were ably performed by Eleanor Anthony and Laraine Crosen, and
much help and useful commentary has been provided by Patricia J. Sheehan,
Editor, and Elizabeth O'Neill, Associate Editor at Butterworths.
HJD
Chapter 1
History Taking in Gastrointestinal
Disease, and Evaluation of
Abdominal Pain
In this book we intend to undertake a thorough examination of the di-
gestive tract, its diseases and their treatment, and to delineate their patho-
physiology 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 diag-
nosis of our patient's problem in the most direct fashion and with the least
discomfort and expense. We commence by suggesting an approach to his-
tory 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 delin-
eate 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 num-
ber of headings, each of which should be investigated thoroughly. It is the
purpose of this section to suggest such an approach.
2 GASTROENTEROLOGY
Pain
Type. Cramplike pain usually suggests hyperperistalsis of the type asso-
ciated with inflammation or obstruction of the small intestine or colon. It is
also encountered frequently with psychogenic or functional alimentary dis-
orders. 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 asso-
ciated 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 help-
ful, 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 duo-
denal disorders commonly produce pain in the right upper abdomen; cecal,
appendiceal, and lower ileal diseases, in the right lower section; and de-
scending 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 psy-
chogenic 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 abdom-
inal pain!
Radiation. Patterns of pain radiation often suggest disease loci. Thus, right
upper abdominal pain which radiates posteriorly and upward to a point be-
tween 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
HISTORY TAKING IN GASTROINTESTINAL DISEASE, AND EVALUATION OF ABDOMINAL PAIN 3
lower dorsal or upper lumbar levels of the back. A psoas abscess may pro-
duce 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 hyperper-
istaltic 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 blad-
der 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, tran-
sient relief from a drink of spirits.
Vomiting often relieves the pain of gastric retention or intestinal ob-
struction, whereas it usually does not affect, or worsens, symptoms of chole-
cystitis 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 sug-
gest the sort of hyperperistalsis that may accompany obstructive or inflam-
matory 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 diag-
nostic value. However, significant and documentable loss of weight is al-
ways 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 require-
ments 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 condi-
tions 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
4 GASTROENTEROLOGY
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 main-
tain nutritional parity. Misdirected appetites for alcohol or drugs also fre-
quently 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 re-
gurgitated because they were sequestered in a diverticulum or were unable
to traverse the full length of the esophagus because of obstruction or muscu-
lar 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 pa-
tients with previous partial gastric resections who also suffer from de-
creased 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 irri-
tation 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 gen-
erally brings prompt relief.
Dysphagia
The patient who complains of difficulty in swallowing almost invari-
ably 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., stric-
ture, cancer or an obtruding mediastinal mass) gradually lead to a progres-
sive form of swallowing difficulty, wherein the patient first experiences
trouble with solid, then with liquid foods. Achalasia is the outstanding