170 PATHOLOGY OF TYPHUS IN MAN 



(i) The bladder: In one case out of thirty-seven a mural 

 thrombus was found in a vein. No other lesions attributable 

 to typhus were found. 



(j) The thyroid: Thirty-four thyroids were studied. In one 

 case only there was a thrombus in a fair sized artery. No 

 other lesions attributable to typhus were found. 



(k) The blood vessels: The aorta was studied microscopically 

 from thirty-four cases. In three, blood vessels in the adven- 

 titia showed lesions with slight peri vascular infiltration. We 

 failed to find the lesions described by Ceelen as reminiscent 

 of syphilitic aortitis; Nicol also failed to do so in twenty aortas 

 from typhus cases. 



Small areas beneath the endothelium filled with large vacuo- 

 lated cells (fat-containing phagocytes) and occasional poly- 

 morphonuclear leucocytes were found in thirteen aortas. 

 These lesions represent acute foci of degeneration of the intima 

 and are common in many infectious diseases. 



Another type of minute lesion was found in ten cases and 

 probably is specific for typhus. This lesion consists of a layer 

 of mononuclear cells, large mononuclear phagocytic cells, and 

 plasma cells lying immediately beneath the endothelium, usu- 

 ally only one row deep and not associated with atheromatous 

 processes. The large mononuclear phagocytic cells (endothe- 

 lial leucocytes) of this lesion occasionally contain inclusions 

 indistinguishable from rickettsia. 



A special study of the left coronary artery was made in four 

 cases of nine, ten, eleven, and eighteen days' duration of the 

 disease. No lesions were found. 



The femoral artery was examined in six cases; in two there 

 were minute mural thrombi and in one of these rickettsia were 

 found. 



The femoral vein was examined in four cases; in one only 

 was there a minute mural thrombus. 



The superior mesenteric artery was examined in eleven cases; 

 in ten there were no lesions, in the case (p. 154) in which there 

 was thrombosis in gross no clue to the origin of the thrombus 

 was found and the parts of the artery selected for sectioning 



