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On the Cutting Room Floor: Historical Research

This post is not funny. Well…maybe it’s funny if you’re also an academic type and have had to cut massive swathes of a paper, but then it’s a laugh-so-you-don’t-cry kinda funny. (Men, for a similar experience, try surfing all day without a shirt and showering the next morning. You shall remember that males also have nipples and you will laugh so you don’t…well…you get the point.)

Anyway, what follows has been cut from a historical paper I have been working on with Dr. Verghese. The overall topic of our research is “The History of Physical Diagnosis Texts in the West.” As, maybe you’ve noticed, I’m very into text, books, history, medicine. It has been wonderful to work on this project. However, it turns out, all the stuff relevant to modern medical practice that we discovered was in the modern era. As such, the following excerpt, which details the course of ancient physical examination texts had to be cut. Wasn’t fun to do, but the two papers that will come out of the research are now far stronger. And there were one or two snarky bits that were going to have to be cut anyway. So, rather than letting the prose vanish into the æther, I thought I’d post it for my readers who are also history buffs. Coincidentally, both of you might want to check out the final papers when they’re out. I’ll post them over my on medicine page.

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Ancient Texts and the Foundations of the Logical Diagnosis

Medical diagnosis requires a belief in the natural, rather than supernatural, origin of disease. Hippocrates, born on the island of Kos near present-day Turkey, founded the first school of professional physicians who separated themselves from contemporary healing cults. The master himself is not known to have written any particular text; rather, a collection of treatises likely authored by him and his students has survived. Written in Ionic Greek—rather than Hippocrates’s native Doric—the treatises were compiled in Alexandra into the Hippocratic Corpus, the first manuscript that might be considered a textbook for the physical examination. Among the surviving treatises are the original Hippocratic Oath and forty-two case histories; some of which demonstrate history taking, inspection, palpation, direct auscultation, succession[1], and examination of the sputum and urine.[2] Here we find that bedside diagnosis and remote diagnosis share the same origin; no history of physical diagnosis exists independent of a history of remote (or later, laboratory) diagnosis.

By combining an understanding of disease as natural with both direct and remote examination, the Hippocratic Corpus established the fundamental principles on which Western medicine would be constructed. However, that construction was long in coming. Classical anatomy was inaccurate and based largely on zoological dissection, while pathophysiology was centered on humorism (imbalance of blood, phlegm, etc). When Rome came to dominate the classical world, Galen—a Greek physician settled in Rome—combined these erroneous understandings with equally invalid Pythagorean theory. Worse, the extensive Galenic Corpus, containing over 500 treatises, came to so dominate the ancient medical mind as to become dogma, thereby arresting rational medical advancement. After the fall of Rome, even the conception of disease as a natural phenomenon declined; many medieval civilizations reverted to the perception of disease as a manifestation of the supernatural—this time invoking demons and devils of the Christian tradition rather than the ancient gods and spirits of the pagan tradition.

Fortunately, Islamic civilizations both preserved and expanded classical medical knowledge, including knowledge of bedside and remote diagnosis. The most important author of this movement was Abu ibn Sina, a Persian polymath and physician often known by his Latinized name, Avicenna. His Cannon of Medicine served as an Arabic medical encyclopedia that drew heavily upon both the Hippocratic Corpus and the Galenic Corpus. Many other physicians throughout the Middle East, North Africa, and the Iberian Peninsula also wrote important medical treatises in Arabic. Most authors were both Arab and Muslim, but there were exceptions: Witness the colorful example of Egyptian-born Isaac Israeli ben Solomon, a Jewish philosopher, former occultist, and physician to a Tunisian Caliph who wrote extensively on uroscopy, a practice that became widespread across the Mediterranean. Ornate flasks, some of them quite beautiful, were crafted to carry urine over great distances for remote diagnosis. The translation of Arabic medical texts into Latin provided non-Muslim European civilizations with access to this learning and therefore the Hippocratic knowledge of patient examination. In particular, the Latin translation of Abu Ibn Sina’s Cannon of Medicine became a standard medical text throughout Europe. Although Arabic medical texts maintained and expanded the classical capacity for diagnosis, they were burdened by the dogma of Galen’s zoological anatomy and a pathophysiology based on humorism.

Hampered by these misconceptions, Western diagnosis remained relatively static and wholly inaccurate for much of the early modern period. Before diagnosis could advance, the Western conception of the body and disease had to evolve. This it did only slowly. In Padua in 1543, Andreas Vesalius defied contemporary Catholic doctrine by publishing On the Structure of the Human Body, establishing a study of anatomy based on human dissection. A hundred years later, a former parliamentary cavalry captain in the English Civil War, Thomas Sydenham, became a physician and published dissertations on the classification of diseases. Observing the result of the period’s deadly plagues, Sydenham argued that diseases could be divided into categories and that a particular disease might manifest differently in different patients save for a few constant and observable characteristics. Over the next century these ideas would develop into the discipline of nosology—the study of disease classification. A nosological conception of disease is so fundamental to the modern mind that most present day physicians would never have heard the word ‘nosology’ and would be hard pressed to imagine a time when classifying diseases was controversial. However, once informed of Sydenham’s contribution, physicians might be tempted to romanticize the pre-nosological past, especially when searching for obscure ICD9 codes.

Starting midway through the seventieth century, similar advancements were made in the understanding of specimen examination. Athanasius Krcher, a Jesuit priest in Germany, applied a microscope to human blood, noting differences in samples taken from patients with plague. Later the writings of Robert Hooke in England and Marcello Malpighi in Italy popularized microscopic examination of tissues. However, little headway was made regarding the clinical application of these developments. Indeed, the era’s most remarkable advance in remote diagnosis came from Thomas Willis, an English physician better remembered for his description of cerebral vasculature. Since ancient times, medical authors had noted that insects would often eat the urine of diabetics. They also discovered—and here one might wish to refrain from imagining exactly how—that this same urine tasted sweet. Willis borrowed the Latin word for honey, ‘mel,’ and named the disease ‘diabetes mellitus.’ This was to be contrasted to those diabetics who produced urine judged to be (relatively, we assume) tasteless or insipid, ergo ‘diabetes insipidus.’ Although pediatricians would later correlate unusually salty sweat with cystic fibrosis, Willis’s discovery marked the apex of the diagnostic sense of taste. One might reasonably celebrate the demise of this particular diagnostic modality; had it been otherwise, modern clinicians might find the current obsession with laboratory diagnosis harder to swallow.

Less sensationally but more importantly, the final foundation of modern diagnostic understanding was created by Giovanni Battista Morgagni, who for more than fifty years carefully correlated patients’ case histories to postmortem findings. In 1761, Morgagni published The Seats and Causes of Diseases, and for the first time, it was possible for a trained physician to inspect a patient’s body or specimen and correctly apply the faculties of deduction or correlation.

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[1] A maneuver in which the patient is shaken while being auscultated to determine the presence of a ‘succession splash’—the sound of fluid and air splashing around in a body cavity. This maneuver is still used today in the bedside diagnosis of gastric outlet obstruction, hydropneumothorax, and pyopneumothorax

[2] Walker, H.K. (1990). The Origins of the History and Physical Examination. In Walker, H.K., Hall, W.D., & Hurst J.W. (Eds.), Clinical Methods, 3rd edition (pg 5) Boston, Butterworths.