Kapronczay Károly szerk.: Orvostörténeti Közlemények 194-195. (Budapest, 2006)

TANULMÁNYOK — ARTICLES - ELEK, Gábor - MÜLLER, Miklós: Ervin Bauer as pathologist

Bauer 's contributions to special pathology In spite of his routine workload and all the difficulties he encountered, especially during his military service, Bauer found time and energy to study several specific problems in depth in this period. In the following we shall briefly discuss these and Bauer's contributions to them. These topics were: (a) thyphus exanthematicus, (b) Addison's disease and other pathological conditions of the adrenal gland, and (c) tumors. {a) Typhus exanthematicus Typhus (typhus exanthematicus) was a major infectious disease affecting the fighting troups during WWI. Its causative agent, Rickettsia prowazeki already has been identified, but its pathogenic role was not yet clarified even in 1921 (Ceelen 1921). The Weil-Felix reaction for the diagnosis of typhus was developed only in 1916 and was not in general use yet. Fraenkel described in 1914 the presence of granulomata around skin blood vessels in typhus exanthemata. The detection of these was helpful in the differential diagnosis between typhus and typhoid fever (spotted fever or exanthematic typhus and abdominal typhus). Bauer demostrated similar granulomata along the arterioles in all organs (Bauer, 1916a, 1916b). By injecting patient blood into Guinea pigs, he produced granulomata experimentally and studied their development (Bauer 1916a). In the comprehensive handbook summarizing the advances of pathology during WWI, Bauer's results are quoted in two chapters dealing with typhus (Ceelen 1921; Fraenkel 1921). „Bauer reports from two skin samples derived from the former site of roséoles of a cured typhus patient typical signs of endarteritis in several corial arteries. Further studies are needed, however, before Bauer's conclusions can be generally accepted that the vascular changes responsible for the typhus roséoles originate from an obstructive endarteritis" (Fraenkel 1921, 124-125). The view today is that ,, Rickettsiae share an affinity for small vessel endothelia, rickettsiosis is dominated by focal vascular inflammation variably associated with rash or with vascular microthrombi, focal ischaemia or hemorrhage. Surrounding the involved vessels a cuff of inflammatory mixed leukocytes is usually present" (Lichtenberg 1989, 330-331). (b) Adrenal glands and Addison 's disease Bauer developed considerable interest in the function and pathology of the adrenal gland and was especially interested in Addison's disease. In addition to detailed evaluation of autopsy material he performed extensive animal studies under difficult conditions. He even had to prepare some of the simplest reagents himself. From a letter to his wife: „ My cats are well tolerating the injections. I almost had problems with uric acid, but I remebered that I kept a fist sized urinary bladder stone from an autopsy, which contains a lot of uric acid. Today I isolated some it thus I have no more problem with this. If everything goes well, I will be finished with this series. I will be satisfied, especially if the results will be good. If you could bring some toluidine blue, I would appreciate it, if not, it will not be a great obstacle" (September 4, 1917; Lenkei 56). A brief summary of the views on adrenal glands and pigment formation in Bauer's times is necessary to provide some background for the discussion of his results.