Eberth, Carl Joseph

(b. Würzburg, Germany, 21 September 1835; d. Berlin, Germany, 2 December 1926)

comparative anatomy, pathology, bacteriology.

Eberth was the son of an artist, who died when Carl Joseph was still young. The boy helped his mother support the family by cutting out silhouette pictures. Nevertheless, he was able to attend the University of Würzburg, where he was drawn to biology and medicine by some of Germany’s foremost teachers: Kölliker, Heinrich Müller, Leydig, and Virchow.

From 1856 to 1859 Eberth worked as an assistant in the Pathological Institute in Würzburg. In the latter year he completed a dissertation on the biology and parasitic characteristics of whipworms and was granted the M.D. degree. He then became a prosector under Heinrich Müller at the Institute of Comparative Anatomy. Here he concentrated on histology, both normal and abnormal. He passed the Habilitation in 1863 and two years later moved to Zurich as extraordinarius in pathology, becoming ordinarius in 1869. From 1874, until his call to Halle in 1881, Eberth also taught histology and embryology in the school of veterinary medicine at the University of Zurich.

In Halle, Eberth was professor of comparative anatomy and histology until 1895, when he assumed directorship of the Pathological Institute. He held the latter position until his retirement at age seventy-five in 1911. As a teacher Eberth was patient and much admired. As a scientist he was thorough, meticulous, and humble, despite wide acclaim for his work.

Eberth married Elisabeth Hohensteiner, a minister’s daughter, in Zurich in 1870. They had three daughters. Eberth was an avid naturalist and mountain climber, activities he continued into his seventies. After becoming emeritus, Eberth lived near Berlin with a daughter. He continued to be in excellent health until shortly before his death.

Eberth is best known for his discovery of the typhoid bacillus (Salmonella typhosa, earlier known as Eberthella typhosa), but this was only one of many important contributions he made in a fifty-year-long career in biological and medical science.

In his earlier scientific papers, many of which were published in Virchows Archiv für pathologische Anatomie, Eberth dealt with the histological structure of various parts of human and animal bodies. Particularly noteworthy were his descriptions of the ciliated epithelium and its function and several papers describing the normal and abnormal microscopic anatomy of the liver. As was true of many comparative anatomists and pathologists about 1870, Eberth became interested in the process of inflammation. He clearly differentiated between epithelial degeneration and regeneration in the cornea, and he was drawn to the study of inflammations caused by microorganisms. Along with Edwin Klebs and very few others, Eberth was instrumental in bringing the studies of bacteria and their actions, in which Davaine and Pasteur in France had pioneered, to the attention of German scientists.

In a remarkable small monograph, Zur Kentniss der bacteritischen Mycose (1872), Eberth set forth the results of his thorough observational and experimental techniques. Especially noteworthy is that this work was carried out four years before Koch dramatically demonstrated the isolation and cultivation of anthrax bacilli. The first part of Eberth’s monograph described his studies of tissues from patients who had died of diphtheria, then a prevalent disease. He saw organisms (not clearly identified as diphtheria bacilli until 1884 by Klebs and Loeffler) that were most plentiful in the exudate covering the tonsils and the necrotic membrane in the pharynx. As a result of his investigations Eberth concluded that the organisms associated with diphtheria appeared first on the mucous membrane or on the edges of wounds. Further growth of the bacteria led to marked tissue destruction. All these conclusions are now known to be essentially correct. He went even further, saying that without these organisms there is no diphtheria (“Ohne diese Pilze keine Diphtherie...”).

In the case of a newborn baby dying of respiratory failure, Eberth described a gelatinous exudate, rich in bacteria, filling the alveoli of the lungs. He did not clearly identify the organisms, but he stained them with iodine and hematoxylin and showed their existence in the heart and spleen as well as in the lungs. In the final section of the monograph Eberth confirmed experimentally what Davaine in France had shown before: that rod-shaped bodies in the blood of animals sick with anthrax were the cause of the disease. He mixed anthrax-infected blood with large volumes of water and allowed the mixture to settle. When he inoculated experimental animals with the supernatant fluid, no infection resulted. The sediment, however, was capable of producing anthrax. These techniques were to become commonplace in the laboratories of Europe during the next decade, but Eberth’s work and his observations made him one of the earliest laboratory bacteriologists. He was thus one of the first of many pathologists seriously to take up bacteriological investigations.

In 1879 Eberth studied twenty-three cases of typhoid fever and reasoned that the characteristic changes found in the spleen and lymph nodes of the abdomen occurred because bacterial activity was most intense in these areas. He found rod-shaped organisms in twelve of his cases and published his results in Virchows Archiv in 1880. While he is, therefore, given credit for discovering the typhoid bacillus, he did so by histopathological techniques. The bacillus was not actually isolated and cultivated until 1884, when Gaffky, a student of Koch’s, was able to grow it. Eberth, along with Koch and others, demonstrated the pneumonia diplococcus microscopically, but he did not cultivate that organism either.

Eberth contributed many papers describing important techniques and discoveries. He described the process of amyloid deposition in tissues and clearly showed that this substance came from outside the cells and was not a product of the cells in the affected areas. Thus, it was not necessarily a degenerative process of the cells that caused the amyloid to appear; rather, the cells were damaged by the amyloid deposited in the spaces between them.

Perhaps Eberth’s major work in pathology was his contribution to the understanding of thrombosis, one of the most common pathological findings. Thrombosis is the process through which clots form in blood vessels during life. Because of its frequency and importance it had received much attention since the earlier part of the century. Virchow, in the 1840’s, and others studied the problem, and most thought it was merely a blood coagulum. In the 1870’s Zahn carried out systematic studies of thrombosis in the frog’s mesentery. By direct observation he noticed that blood cells were deposited on the inner wall of the blood vessels and continued to accumulate in layers until the lumen became completely occluded. Zahn thought the cells were mainly white blood cells. Georges Hayem and Bizzozero in the early 1880’s implicated blood platelets. In the mid-1880’s Eberth, with his pupil and assistant Curt Schimmelbusch, who later became instrumental in perfecting the aseptic technique for surgery, carried out a thorough study of the role of the platelets.

Eberth and Schimmelbusch, by means of meticulous microscopic studies of experimentally induced thrombi, concluded that slowing of the flow of blood or injury to the inner lining of the vessel caused platelets to adhere to the wall, forming the beginning of a plug. By a process of viscous metamorphosis, now better understood, they believed the platelets adhered to one another and attracted red and white cells as formation of the thrombus continued. Eberth and Schimmelbusch called this process conglutination and were careful to distinguish it from coagulation, which they regarded as a later event in the development of the thrombus.

While some of the details of their explanation were disputed, Eberth and Schimmelbusch’s major conclusions—that it was the platelets that were first involved, and that a combination of injury to the vessel and slowing of the blood flow were necessary for thrombosis to occur—have essentially stood the test of time. Their papers and subsequent monograph of 1888 do not give them priority of discovery, yet they deserve major credit for summarizing and elucidating the process in modern terms.

In Zurich and Halle, Eberth had many students. As an aid to them and students everywhere he undertook in 1889 to bring out a new edition of a widely used manual of techniques for pathological studies written by Carl Friedländer. Eberth contributed substantially toward making this popular book even more useful in the fourth and fifth editions. He nearly doubled the text, added many illustrations, and provided an index. Thus, Eberth was able to communicate to others the methods of microscopic investigation of tissues and cells that he had so successfully. used himself.

BIBLIOGRAPHY

I. Original Works. Much of Eberth’s work was reported in the major German and Swiss medical journals. He was a frequent contributor to Virchows Archiv für pathologische Anatomie, where some of his major discoveries appeared, including “Untersuchungen über die normale und pathologische Leber,” 39 (1867), 70–89; 40 (1867), 305–325; “Die amyloide Entartung,” 80 (1880), 138–172; “Die Organismen in den Organen bei Typhus abdominalis,” 81 (1880), 58–74; and “Neue Untersuchungen über den Bacillus des Abdominaltyphus,” 83 (1881), 486–501.

The major monographs were Zur Kentniss der bacteritischen Mycose (Leipzig, 1872); Die Thrombose nach Versuchen und Leichenbefunden (Stuttgart, 1888), written with C. Schimmelbusch; and new eds. of Carl Friedländer, Microscopische Technik zum Gebrauch bei medicinischen und pathologisch-anatomischen Untersuchungen (4th ed., Berlin, 1889; 5th ed., 1894).

II. Secondary Literature. See the following, listed chronologically: H. Ribbert, “Karl Joseph Eberth zum 70. Geburtstag,” in Deutsche medizinische Wochenschrift, 31 (1905), 1511–1512; R. Beneke, “Zu Carl Josef Eberth’s 80. Geburtstag,” in Berliner klinische Wochenschrift, 52 (1915), 1010–1013; and “Carl Josef Eberth,” in Zentralblatt für allgemeine Pathologie und pathologische Anatomie, 39 (1927), 226–228; W. Wachter, “Carl Joseph Eberth,” in Apothekerzeitung, 42 (1927), 310–313; R. Beneke, “Zur Erinnerung an Karl Joseph Eberth,” in Münchener medizinische Wochenschrift, 82 (1935), 1536–1537; Ernst Galgiardi, Hans Nabholz, and Jean Strohl, Die Universität Zurich 1833–1933 und ihre Vorläufer (Zurich, 1938), pp. 564–565; Heinrich Buess, “Carl Joseph Eberth,” in Les médecins célèbres, R. Dumesnil and F. Bonnet-Roy, eds. (Geneva, 1947), pp. 196–197, trans. into German in Die berühmten Ärzte, R. Dumesnil and H. Schadewaldt, eds. (Cologne, 1966), pp. 235–236; and H. von Meyenburg, “Geschichte des pathologischen Instituts,” in Zürcher Spitalgeschichte, 2 vols. (Zurich, 1951), II, 559–580, esp. 565–566.

Gert H. Brieger