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UNDER
THE MICROSCOPE THE EVOLUTION OF PATHOLOGY
AND LABORATORY MEDICINE IN CANADA
HARRY
LETTS, MD
JOHN JACQUES, MD
CHAPTER
1
INTRODUCTION
Although there are several books and articles
dealing with the History of Pathology in general, none as yet describe in
a comprehensive fashion, the evolution and development of this medical
specialty with emphasis on CANADA. This
present treatise is an attempt to fill the gap, with particular attention
on the early years leading up to the formation in 1949 of the Canadian
Association of Pathologists and
the subsequent development of that organization.
Dr. Oskar Klotz (1878-1936) the Professor
and Head of the Department of Pathology at the University of Toronto from
1923 to 1936 apparently had planned to write a History of Pathology in
Canada but unfortunately never completed the project.
Many of his books and papers are still however available at the
Fisher Rare Books Library in Toronto and the National Archives in Ottawa
and have been a valuable resource for this work.
Dr. Esmond Long (1890-1979) of the United
States, pathologist, epidemiologist and historian wrote a very general
text on “A History of Pathology” which was printed in 1928. Another of his books entitled “A History of American
Pathology” published in 1962, contains significant reference to
pathology in Canada and these are frequently referred to here.
In addition, the paper by medical historian Dr. E.T. Mormon titled
“Clinical Pathology in America 1865-1915” has been most useful in
establishing the pattern of the early growth and development of Laboratory
Medicine in this country.
Books and individual papers on the
History of Pathology in other countries have also appeared over the years,
and are helpful in establishing general trends and patterns.
Several accounts of Canadian Medical History have been published,
in which there is mention of outstanding Canadian pathologists or
laboratory physicians. These
are usually in the context of the role of these men and women in the
development of medical schools or hospitals, their involvement in a
scientific discovery, in the inauguration of a journal or a society, or
more generally in the Canadian medical
scene but once again a systematic approach to their role in the
development of pathology is lacking.
In 1981 S.E.D. Shortt of McGill, a
historian, wrote: “Medical Historiography (a body of historical writing)
in Canada is American Historiography writ small, the same trends and
patterns, though of lesser degree, are evident”.
This is also true for pathology, but probably could be paraphrased
to state “The History of Pathology in Canada is British (mostly
Scottish) Pathology writ small, for the trends are similar” (but usually
a half a century later) having been influenced by the large number of
immigrant pathologists from the British Isles.
In addition it is obvious that as the country developed at a
different pace in the larger urban Eastern cities - Halifax, Montreal and
Toronto, compared to the West - Winnipeg, Edmonton and Vancouver, so of
course did the growth of Pathology and Laboratory Medicine.
Before beginning this study it is first
important to define the topic and its scope.
The word Pathology is derived from two Greek words: pathos meaning
“suffering, disease, or feeling”’ and logos, a word termination
meaning “the science or study of”.
Pathology is defined in Webster’s New
World Dictionary of 1953 as “that branch of medicine that deals with the
nature of disease especially with the structural and functional changes
caused by disease”; in the Oxford 1984 pocket dictionary as “the
science of bodily diseases”; and the 1990 Bantam Medical Dictionary
notes “Pathology is the study of disease processes with the aim of
understanding their nature and cause.
This is achieved by observing samples of blood, urine, feces and
diseased tissue from living patients or at autopsy, and by many other
techniques”.
Over the years, however, many other
definitions have been applied to pathology, the pathologist and the
pathology laboratory. In
1924, a joint adhoc committee of “several American American Laboratory
Societies, Councils and Associations” defined:
“a clinical pathological
laboratory is an institution organized for the practical application of
one or more of the fundamental sciences by the use of specialized
apparatus, equipment and methods for the purpose of ascertaining the
presence, source and progress of disease in the Human Body”.
During his presidential address to the 4th
annual meeting of the Ontario Association of Pathologists in 1942,
well-known Canadian pathologist William J. Deadman noted:
“Wherever in the long
reaches of time, one sees an individual more observant and logical than
his fellow, who scans the criteria of disease, associates them with
coincidental body changes, and formulates a theory as to etiology, there
one sees a pathologist.”
In 1960,
the Directors of the American Board of Pathology (ABP founded in
1936) stated:
“For the
purposes of the ABP, Pathology is defined as that specialty of the practice of Medicine dealing with the causes and nature
of disease, which contributes to diagnosis, prognosis and treatment
through knowledge gained by laboratory applications of the biologic,
chemical or physical sciences to man, or material obtained from man.”
All of the preceding definitions stress the
very broad scope of Pathology but in more recent years, some have
expressed concern that the term Pathology was becoming too limited and was
often taken to mean only anatomic, tissue or forensic pathology.
The use of the terms Laboratory Medicine and Laboratory Physician
is being advocated, but while this terminology has been the topic of many
debates particularly in Canada over the years, all agree and continue to
emphasize the comprehensive nature of the discipline. Thus, in 1981, Dr. Edward Mormon, noted medical historian,
during a speech in Toronto to the 54th annual meeting of the Association
for the History of Medicine stated that:
“Pathologists are doctors
who do seek opportunities to perform autopsies, but are equally anxious
to examine tumours, or blood samples, and to search for microscopic
pathogens. Their workplace has to be converted from a morgue and museum
into a laboratory which communicates directly with the ward or operating
room.”
In a 1982 report to the Ontario Council of
Health by a Task Force on Laboratory Services, the following definition of
Laboratory Medicine was accepted as appropriate (somewhat paraphrased):
“Laboratory
Medicine (Pathology) is a specialty in the practice of medicine which
encompasses those disciplines involved in the examination, interpretation,
and reporting of specimens from,
or tests performed on, the human body or the environment, for the
prevention, diagnosis and treatment of disease.
Laboratory Medicine encompasses aspects of research
and environmental studies related thereto. It is implicit that the interpretation and reporting of
laboratory tests performed on a patient or a specimen under the direction
of the laboratory physician involves a physician-patient relationship and
therefore constitutes a medical act.
A significant component of this specialty is the provision of a
consultative service to other practitioners of medicine, including at
times examination of patients, review of biological samples in conjunction
with the patient’s record, and participation in monitoring the
utilization of laboratory services.”
A 1992 brochure produced by the Intersociety
Committee on Pathology Information titled, “Pathology as a Career in
Medicine” states:
“Pathology
is a medical specialty which provides the scientific foundation for
medical practice. The
pathologist works with all other medical specialties, using the tools
of the laboratory to provide information essential to problem
solving in clinical practice. All
pathologists share a fascination with the process of disease, its
scientific meaning, its logic, its mystery, and its intellectual
challenge. Pathologists
practicing in hospital laboratories have access to the knowledge gained
from the examination and treatment of large numbers of patients.
As consultant physicians, they apply this knowledge to assist in
diagnostic and therapeutic problem solving for individual patients.
As medical scientists, they make contributions that advance the
understanding of disease. As
teachers, they impart this understanding to their medical colleagues, to
house staff and to students.”
A similar recruiting document prepared at
about the same time by the Canadian Association of Pathologists notes:
“A pathologist is a medical
doctor with specialized training in how to use laboratory methods to
make medical diagnoses. A
more descriptive name for a pathologist is a Laboratory Physician.
The field of pathology (or Laboratory Medicine) encompasses
several disciplines, which include Anatomic (Tissue) Pathology,
Cytopathology, Forensic Pathology, Haematological Pathology,
Microbiology and Medical Biochemistry. Some laboratory physicians have a broad-based training and
provide services in several of these areas, and are known as General
Pathologists. Others are
more specialized and concentrate on a single area.”
Pathology has therefore developed to
encompass all areas of Laboratory Medicine but there is no doubt that it
commenced with the gross examination of the human body at autopsy and has
grown through technological advances.
In the 7th Edition of Dr. William Boyd’s textbook “An
Introduction to the Study of Diseases” (1977) is the statement that:
“The three major steps in the
development of Pathology in the past are;
-
The development of dissection of the human
body.
-
The use of the microscope in the examination
of pathologic tissue.
-
The introduction of Chemistry and
Biochemistry in the investigation and treatment of disease.”
These steps are indeed reflected in the
early Canadian History of Pathology.
Moreover, as Dr. W.D. Foster of Great Britain noted in 1980, there
was no such thing as a professional pathologist in Great Britain before
1826, a profession being defined as “persons earning a living by the
practice of special skills and possessed of expert knowledge in a certain
field of endeavour”. Prior
to this, dissection of the human body and the study of disease fell
largely into the domain of anatomists, general physicians or barber
surgeons. It is not
surprising that the same is true in Canada.
In more recent years, other discoveries have
led to significant change in the practice of pathology or laboratory
medicine. Thus advances have
been achieved in biochemical methodology, chromatography, atomic
absorption spectrophotometry, radioimmunoassay, therapeutic drug
monitoring and automated techniques such as continuous flow and thin film
analysis, the development of techniques for the investigation of
microbiological disease, advances in serology technique and the
introduction of antimicrobial agents and their measurement, and the
continued development of the microscope - polarizing, phase contrast,
darkfield, UV, and fluorescent microscopes.
Then the electron microscope (the first electron microscope in
North America was built in 1934 by professor Burton of the Physics
Department at Toronto); exfoliative cytology (Papanicolau et al),
immunology, human genetics and molecular biology; histochemistry and
immunocytochemistry; the increasing role and influence of electronics,
automated cell counting, the computer sciences and more recently,
robotics; all have had and will continue to have an influence on the
specialty.
External factors have also been influential
in shaping the face of pathology over the years.
The prevalence of infectious diseases in the early years and the
emergence of new ones latterly have dictated changes in pathology
practice. Economic
circumstances have never been far from the forefront.
The development of ever larger independent laboratories in the 1950’s,
1960’s and 1970’s was but a precursor to the growing influence of
large commercial laboratories in the 1980’s while the 1990’s saw a
wave of mergers, consolidations, closures, and cutbacks in public and
private sector alike. These
have raised many questions regarding the future of the very profession
itself.
But to begin at the beginning...
CHAPTER
2
THE EARLY TIMES
In 1536, barber-surgeon Samson Ripault
performed the Post Mortem examination ordered by explorer Jacques Cartier
(1491-1557) while on a voyage on the St. Lawrence River. The examination
revealed that a 22 year-old seaman had died of scurvy. This autopsy which
is said to be the FIRST RECORDED PATHOLOGICAL EXAMINATION in Canada
occurred 40 years after John Cabot first reached the shores of
Newfoundland and 30 years after the first major collection of autopsy
reports was published by Antonio Bonivieni (1440-1502) in Europe in 1506 -
said to be the FATHER OF PATHOLOGIC ANATOMY.
A year previously, Cartier had visited
Hochelaga on Montreal Island and the Indians there believed he had curing
powers. The Indian chief caused “the sick, the maimed, the halt and the
blind of his tribe to be brought before him”. Some historians feel that
this episode could be considered the FIRST RECORDED INSTANCE OF THE
DIAGNOSIS AND TREATMENT OF DISEASE IN CANADA!
There had been earlier post mortem
dissections of the human body in Europe, often at public display in the
1400’s. These autopsies however, were confined to cursory gross
examination of the organs performed by physicians or barber-surgeons on
their own patients to attempt to determine the immediate cause of death,
without particularly relating any lesions seen with the patients symptoms
and signs before death. Sometimes if the person died under suspicious
circumstances like being alone in the street or with a bullet hole in the
forehead, autopsies were ordered by the coroners of the time, or
occasionally at the behest of the local law schools and performed by
whomever they could get to do them - often by subpoena!
It was only with the coming of the
Renaissance that systematic anatomic and pathological studies and their
dissemination laid the foundations of modern knowledge. The anatomical
studies of Belgian ANDREAS VESALIUS (1514-1564) and the publication of his
“De humani corporis fabricus” in 1543 corrected misconceptions in
place since the time of Galen and others from the Second to the Twelfth
Centuries.
In Canada, historical records appear to
indicate that during Samuel de Champlain’s time, autopsies were
regularly performed and careful records maintained. Some of these
autopsies were undoubtedly performed by Surgeon-Barber Robert Giffard
(1622-1668) the first surgeon at Quebec’s Hôtel Dieu, the first
hospital in America north of Mexico City; and Ship`s Surgeon (and
Botanist) Michel Sarrazin (1659-1734).
In 1761, Italian GIOVANNI BATTISTA MORGAGNI
of Padua (1682-1771) regarded by many as the FATHER OF MODERN PATHOLOGY
published “De Sedibus et Causis Morborum”. This treatise was the first
to fully correlate symptomatology with the gross changes in the organs at
the autopsy.
“This work was the result of almost 60
years of observation and leisurely contemplation, and included thorough
clinical histories and meticulous descriptions of autopsy findings along
with copious reference to previous literature.”
Then 30 years later, John Hunter of Great
Britain (1728-1793), one of the foremost surgeons of the time organized an
extensive museum of anatomical specimens, and in 1793 Hunter’s nephew,
Matthew Baillie (1761-1823) published the first illustrated systematic
handbook of anatomic pathology entitled “The Morbid Anatomy of Some of
the Most Important Parts of the Human Body”, based in part on study of
these specimens. In addition, at about this time, MARIE F.X. BICHAT
(1771-1804) performed detailed dissections and introduced various methods
for “fixing” tissues. He is said to be the PATRIARCH OF TISSUE
PATHOLOGY although he never used the microscope! Anatomic pathology thus
became the first of the laboratory specialities to be established and
chairs in Pathologic Anatomy were appointed in Caen in 1756, in Strasbourg
in 1819 and in Paris in 1836.
In the late 1800’s an Austrian CARL
ROKITANSKY (1804-1878) and his assistants performed over 30,000 - yes,
thirty thousand autopsies and not only improved descriptive pathology but
almost by definition could be considered the first “full-time”
anatomic pathologist (morbid anatomist). Rokitansky’s technique for
dissecting the body are standard in many institutions to this day, and the
autopsy reports of many present day pathologists read much like those of
these early times.
The development of the simple lens
microscope by Robert Hooke (1635-1703) and compound lenses by Dutchman
Antony van Leeuwenhoek (1632-1723) in the late 1600’s set the stage for
later advances in medical knowledge by such scientists as MARCELLO
MALPIGHI (1628-1694) of Bologna considered to be the FOREBEAR OF
HISTOLOGY.
However, it was only in the second half of
the 19th century (1860) that CELLULAR PATHOLOGY became firmly established
predominately through the microscopic work of German pathologist RUDOF
VIRCHOW (1821-1902). Virchow solidified the cellular theory of life with
his famous statement: “OMNIS CELLULA E CELLULAE - All cells come from
cells”. As we will see, many of the early Canadian laboratory physicians
served with Virchow at some point in their training, or were deeply
influenced by his teachings, or by his pupils.
Post mortem examination and the ever
expanding utilization of microscopic study of tissues, continued to be the
major activity of pathologists until the mid 1800’s. Between 1840 and
1890 the invention of the traversing stage by Patrick Freeland of Toronto
in 1857, and of the condenser and achromatic lens by Ernst Abbe in 1878
improved microscopy. The advances in tissue preparation such as the
introduction of better fixatives, newer quick freezing methods (CO2 and
nitrogen), and histological technique (improved stains), the evolution of
the freezing microtome and ultramicrotome, continued to allow more
sophisticated study not only of tissues obtained at autopsy or at surgery,
but of bodily fluids obtained from living patients (the latter often
called CLINICAL MICROSCOPY).
The texts of Englishmen Thomas Willis
(1621-1675) titled “Treatises on Urine” (1674), Chemist Robert Boyle
on “Memoirs for the Natural History of Humane Blood” (1684), and
William Harvey (1578-1657) on “The Circulation of the Blood” (De Motu
Cordis) (1628), and then a century later, the writings of FELIX HOPPE-SEYLER
(1825-1845) said to be the FOUNDER OF CHEMICAL PATHOLOGY among others, all
provided the basis for the future development of so called CLINICAL
PATHOLOGY (Laboratory Medicine). Bronne Langrish proved to be farsighted
when he stated in the Modern Theory and Practice of Physic (London 1735)
“that the study of the proportions of
several principles of blood and urine, both in a sound and disease state
will be highly useful in investigating the causes of the phenomenon of
disease”.
However, relatively simple chemical tests on
blood and urine, such as - non protein nitrogen, urea, glucose, and
bilirubin - most often performed in a “sideroom” next to a hospital
ward by a “Houseman”(intern), were the only laboratory analytical
procedures - clinical chemistry - performed in hospitals or anywhere else
for that matter, for many years.
During this time as well, the work of an
English surgeon JOSEPH LISTER (1827-1912), LOUIS PASTEUR a French chemist
(1822-1895), and ROBERT KOCH of Germany (1843-1910) led to remarkable
advances in microbiological investigation. Many pioneer Canadian
physicians also trained with these outstanding investigators or with their
pupils. Between 1880 and 1890, searching under the microscope for TB
bacilli, cholera vibrio, pneumococci, and diphtheria, and later performing
Widal and Wasserman tests, continued to occupy the efforts of clinicians
or housestaff until the earliest microbiology laboratories with trained
specialized staff were developed. Significant haematological investigation
progressed beyond haemoglobin determination and examination of the blood
smear only after 1900.
The early growth and development of the
speciality of Pathology in the late 18th and early 19th centuries followed
the same basic pattern albeit at a slower pace in Canada (and the United
States) as in Europe. During this period, except for the post mortem
examination, there was limited laboratory medicine practised as a full
time profession in this country until the first Canadian Medical Schools
established.
As previously noted, in North America the
provision of a diagnostic laboratory service as a speciality developed at
about the same time as other medical and surgical specialities. These
specialities were usually not only linked to the advances in medical
science in general, but particularly related to the invention of an
appropriate instrument or piece of equipment and the associated skills
required to efficiently use them, i.e. ophthalmology and the
ophthalmoscope. The first such clinical specialist in Canada was Dr. Abner
M. Roseburgh of Toronto who decided to “confine” his practice, when he
opened and “eye and ear infirmary” in 1863, with extensive use of the
“ophthalmo-otoscope”.
Dr. WILLIAM HENRY WELCH (1850-1934) of the
United States should be considered as the FATHER OF MODERN PATHOLOGY IN
NORTH AMERICA. He received a MD at Columbia University in New York in
1875. Then postgraduate training in Europe with the likes of Cohnheim,
Ehrlich and Koch. In 1884, Welsh became Professor of Pathology at the new
John Hopkins Medical Institution in Baltimore, U.S.A.
“He established the concept of the
Laboratory as the centre for a career in Pathology and the importance of
combined teaching and reasearch for progress”.
Welsh’s influence spanned the entire
breadth of medicine not just pathology, from scientific research to
clinical practice. He was instrumental in bringing together “the big
four of OSLER, KELLY, HALSTEAD and himself” at Johns Hopkins, who would
train or influence numerous future pathologists and laboratory physicians
over the next half-century.
In Laboratory Medicine it is generally
believed that Dr. GEORGE DOCK operated the first American CLINICAL
LABORATORY at the University of Michigan in the USA in 1893. However, in
Canada during the same year, a “Clinical Pathology” wing was part of
the recently developed Royal Victoria Hospital in Montreal. Dr. John Caven
(1819-1913), a professor at the University of Toronto’s Medical School,
also “operated a clinical laboratory” at the Toronto General Hospital
at this time. Then in 1895, Dr. W.T.Connell (1873-1964), the recently
appointed Chairman of the Department of Pathology at Queens University in
Kingston at the age of 23, set up a laboratory and offered “a wide
variety of analyses for the practicing physicians in Eastern Ontario”
(including chemical testing).
Dr. N. Tait McPhedran of Calgary in his 1993
Anthology of Canadian Medical Schools, noted that the system of Medical
Education in this country could not have evolved without the early
hospitals. Similarly, not only hospital development but the explosion in
knowledge of the diagnosis of infectious disease, and the associated
establishment of Provincial Public Health Laboratories, stimulated growth
in the profession of Laboratory Medicine.
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