PATHO-HISTOLOGICAL STUDIES ON THE HAERT OF DIPHTHERIA

Abstract

The heart in 7 cases of malignant diphtheria was studied grossly and microscopically. With an intention of clarifying the changes of the heart of diphtheria, experimental study was also done.
Conclusions and results were as follows.
1. The increase in weight of the heart was observed in almost all cases, and the mean increased weight was 40g.
2. The dilatation of the left ventricle was characterisric and in became more marked as the hopital days passed.
3. The myocardial lesion of diphtheria was due to diphtheria toxin.
4. Microscopically, varying degrees of degenerative changes (granular degeneration, hyaline degeneration vacuole degeneration, fatty deseneration) and liquefactive necrosis, myolysis of the muscle fibers were associated with the interstitial changes which developed secondarily to myocardial lesions and they consisted of edema, congestion, histiocytic and lymphocytic infiltration.
In cases of acute course the interstial changes were hardly recognized. Those afore-mentioned changess were noted on the 5th day of illness, the degrees of myocardial lesion progressed as the day passed. They were most prominent on 17th day of illness.
5. Myocardial lesions were noted at the anterior and posterior walls of the left ventricle, especially in the vicinity of the endocardium. The sites of myocardial lesions in diphtheria, therefore, were similar to those in myocardial infarction.
6. The animals used were rabbits and Schick's solution were given by intramuscular injection. In the group received 2 minimal lethal doses of Schick's solution, the same myocardial lesionsas above-mentioned was identified. But in the group received 2 minimal lethal doses of Schicks solution and antiphtheric serum simultaneously, the myocardial changes were not revealed.