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Evolution of the Language of Tuberculosis
The disease tuberculosis has many names that mirror human thought about it during past ages. The Greeks knew tuberculosis by the name of phthisis (pronounced “TEE-sis”). Related Greek words phthiein and phthinein meant to pass or waste away. (1) Phthoe was the name Greek physicians gave to individuals shriveling up under intense heat. (2) Phthisis evolved to mean the wasting and melting away of the body caused by disease of the lungs. (2) The Greek physician Hippocrates (ca. 460 B.C.-ca. 370 B.C.) first observed phymata (Greek, plural of phyma, a growth) in the tissues of cattle, sheep and pigs. (3) Some tuberculosis specialists today call themselves phthisiologists. (4-5) Italian physician Hieronymus Fracastorius (1478-1553 A.D.), who recognized the contagiousness of tuberculosis and proposed a scientific germ theory of disease more than 300 years before its empirical formulation by Louis Pasteur and Robert Koch, used the Latin word tabes to denote the progressive wasting, or emaciation, that characterized phthisis. (6,7) Consumption in the seventeenth century became the most common word used in all languages to express the striking emaciation of patients with end-stage pulmonary tuberculosis. (6) English physicians in the early 1600s derived consumption from the Latin consumere, meaning to eat or devour, to describe the fever and anorexia experienced by their tuberculous patients. Consumption rapidly entered the vernacular in the eighteenth century when lay people and physicians alike applied it to disease entities other than phthisis, including diabetes and cancer. The Englishman Benjamin Marten in 1720 A.D. proposed a scientific germ theory for tuberculosis in his remarkable 186-page book titled A New Theory of Consumption, More Especially of a Phthisis or Consumption of the Lungs 163 years before Robert Koch’s discovery of the tubercle bacillus (more below). (8) Briefly, Marten’s theory stated “the prime, essential, and hitherto accounted inexplicable cause of that disease” was, in fact, “animalculae fretting or gnawing the vessels of the Stomach, Lungs, Liver”. Marten expresses below the common meaning of consumption during his time: “Custom has now so much prevailed with Physicians that whenever they speak of a Consumption it is generally and more especially take for a Phthisis or that Consumption of the Body which has its rise form an Ulceration of the Lungs. “A Phthisis or Consumption of the Lungs may be very justly defined to be a wearing away or consuming of all the muscular or fleshy Part of the Body, accompanied with a Cough, purulent Spitting, hectic Fever, shortness of Breath, night Sweats, etc.” (6) Marten’s clever ideas about the cause of consumption unfortunately did not fall on fertile ground, and when historians rediscovered Marten’s book in 1911, only four copies of it could be located. (9) Meanwhile European physicians in the seventeenth century had initiated the anatomo-pathological era of medicine by beginning to perform autopsies to obtain information on the causes of death of their patients, including consumptives. (10) They soon found that the wasting of phthisis was constantly associated with the presence of lesions in the internal organs of the body, an observation noted by Hippocrates (phymata) in pigs two thousand years earlier. The French Renaissance physician Jean Francois Fernel (1497-1558 A.D) described cavities in the phthisical lung and called them vomicae. (6,11) Physician Franciscus de (Sylvius) Le Boe (1614-1672 A.D.) in his Opera Medica published in 1679 A.D. wrote about characteristic nodules, which he called tubercles, in the lungs, but also in other parts of the body. (12,13) Further, these tubercles tended to suppurate and ulcerate, giving rise to cavities filled with cheesy material. In 1790 the Scottish physician Matthew Baillie, who died of tuberculosis in 1823 A.D., further described the cheesy material in some tubercles, now called caseous material. Physicians and scientists argued about the origin and identity of tubercles until German physician Robert Koch (1843-1910 A.D.) arrived on the scene. Leveraging the compound microscope, developed and popularized by Dutchmen Cornelius Drebbel (1572-1633 A.D.) and Antonj van Leeuwehoek (1632-1723 A.D.), Koch discovered the microbe cause of consumption, which he called “Tuberkelbazillus” (in English, tubercle bacillus) because he found the bacilli in material from (mostly lung) tubercles. (14) Also called Koch’s bacillus, it initially received the taxonomic name Bacterium tuberculosis to distinguish it from Bacterium leprae, discovered in 1873 by Norwegian G.H. Armauer Hansen. (15) In 1896, bacteriologists Karl Lehmann and Rudolf Neumann proposed the genus Mycobacterium to include both the tubercle and the leprosy bacilli. (16-17) The word Mycobacterium derives from the Greek noun myces, fungus; the Greek noun bakterion, a small rod; and the Middle Latin noun Mycobacterium, a fungus rodlet, “fungus bacterium” or fungus-like bacterium. (18) The name does not imply that mycobacteria are fungi; rather it describes the way that the tubercle bacillus grows on the surface of liquid media as mold-like pellicles when cultured. (19) When taxonomists allocated Bacterium tuberculosis and Bacterium leprae to the genus Mycobacterium, they morphed into Mycobacterium tuberculosis and Mycobacterium leprae. (20) In 1975 microbiologist Ernest H. Runyon (1884-1999 A.D.) proposed that the century-old term tubercle bacilli should include several similar species discovered after Koch’s initial discovery. The species were Mycobacterium tuberculosis, Mycobacterium bovis, and Mycobacterium africanum, and no others. (20) Deoxyribonucleic acid (DNA) hybridization studies in the 1980s strongly suggested joining the three species (and M. microti) under the one term M. tuberculosis. The new name for this group is Mycobacterium tuberculosis complex, or M. tuberculosis complex. The arrival of the acquired immunodeficiency syndrome (AIDS) and organ transplantation, among other immune system-compromised states thrust the ubiquitous environmental nontuberculous species of Mycobacterium (NTM), of which there are about 65 different species, onto center stage as the causative agents of mycobacterial infection, colonization, or pseudoinfection in humans. (21,22) Microbiologists Moeller, Lehmann and Neumann by 1899 had already isolated
these saprophytic mycobacteria from swamps, puddles and the surface of plants,
as well as from soil and decomposing organic matter in the environment. (23) When
these opportunistic pathogens gain access to immunocompromised humans via,
for example, tainted hospital water supplies, nontuberculous mycobacterial
disease (tuberculosis) may result. AIDS patients are especially prone to Mycobacterium
avium complex (MAC) spread, for example, by tuberculous bird droppings
that enter the drinking water supply. Mycobacteriosis (infection with mycobacteria) caused by nontuberculous mycobacteria may afflict humans and animals. For example, humans and birds may acquire each M. avium complex microbes from the same environmental source. Thus, nontuberculous mycobacteriosis is not a zoonosis. (26) A zoonosis is any infectious disease that may transmit from wild and domestic animals to humans, or from humans to animals (the latter case is reverse zoonosis). The principal agent of zoonotic tuberculosis is M. bovis (from animals to humans). The principal agent in reverse zoonotic tuberculosis is M. tuberculosis (from humans and other primates to animals). For example, transmission of M. bovis from cattle to humans via the latter’s ingestion of raw milk products is an example of zoonotic tuberculosis. (27) Similarly, transmission of M. tuberculosis from humans to circus elephants is an example of (reverse) zoonotic tuberculosis. (28) Scrofula (struma, strumous glands) is a form of tuberculosis affecting the lymph nodes, especially of the neck, that is most common in children, usually spread by ingestion of unpasteurized (raw) milk or milk products from tuberculosis-infected cows. (29) It derives from the Late Latin scrofulae, meaning swelling of the glands, after scrofa, a pig. The idea is that the cervical glands of a scrofulous person resemble a swine’s full neck. (30) Dr. William Osler in 1898 defined galloping consumption, or phthisis florida, as acute caseous tuberculous broncho-pneumonia. (31) It was a frequent diagnosis in the nineteenth century. (32) Osler noted that it starts in the smaller bronchial tubes soon blocked by a cheesy substance, while the lung’s air-cells fill up with the products of a “catarrhal pneumonia”. Galloping consumption occurs “in the acute phthisis of adults, but it is still more frequent in children.” One example cited by Osler is a child aged four months who died of galloping consumption in the sixth week of illness. (31) Finally, observers have postulated the existence of a state--spes phthisica—entered by tuberculous individuals, particularly young talented individuals, who display enormous intellectual capacity of the creative kind, e.g., romantic poet John Keats (1795-1821) who died of tuberculosis at age 26 years. Many tuberculous individuals have “dazzled the world by the splendor of their emotional and intellectual gifts and by the passionate energy with which they exploited their frail bodies and their few years of life in order to overcome the limitations of the disease.” Some observers “believe that their infirmity was the cause of the consuming restlessness that drove them on to artistic creation.” (33) Notes:
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