125 



FIBRIN FORMATION IN THE GLANDS AND IN THE 



OTHER ORGANS. 



The homogeneous material just described is not true fibrin, and 

 does not give the tinctorial fibrin reaction of Weigert. However, 

 in plague true fibrin is found in the primary bubo in quite a number 

 of cases as well as in the organs distant from the focus of infection. 

 We encounter perfectl}' solid hyaline fibrin thrombi, or some vessels 

 may be partly occluded by a hollow tubular wall thrombus or by 

 a more or less open reticulum of fibrin. Such reticula, particularly 

 in the bubonic glands and in the spleen, are also found in an extra- 

 vascular location. Occasionally one sees threads connecting the 

 intravascular and extravascidar fibrin reticula. Sometimes fibrin is 

 found, not in the shape of threads, but as granular, more or less 

 solid material, always of course giving a typical Weigert's reaction. 

 In the glandular buboes we observed fibrin in the shape of hyaline, 

 vascular thrombi, or in the form of extravascular fibrin reticula, 

 with or without a connection of the intravascular and extravascular 

 deposits (in seven cases, Nos. 2, 9, 10, 11, 12, 15, and 20). Further 

 fibrin formation was observed in the spleen in five cases (jSTos. 5, 

 10, 11, 12, and 20), and in the lungs in three (Nos. 17, 18 and 19). 

 Fibrin may be found in several organs in the same case (No. 10, 

 in the primary bubo, the spleen, and the kidneys) ; or it may be 

 found in the primary bubo and nowhere else (Xos. 1, 3, 7, and 17) ; 

 or it may be encountered in the organs distant from the primary 

 bubo without being present in the latter (Nos. 11, 12, and 15). 

 In cases Kos. 18, 19, and 20, types of primary pneumonia and 

 primary septicsemia, there were of course no lymphatic buboes 

 present and no fibrin was observed in any of the lymph glands. 

 Fibrin thrombi in the kidneys were found in seven cases. (See 

 below "Hyaline Fibrin Thrombi of the Glomerular Capillaries.") 



HEMORRHAGES INTO THE BUBO AND INTO THE 

 DISTANT ORGANS. 



In studing the histopatholog}' of the infected hinph glands we 

 encounter other changes besides fibrin formation. These changes 

 are quite characteristic for plague and are found not only in the 

 glands but in locations distant from the focus of infection. 



The feature which is most characterictic of plague infection is 

 its tendency to produce a general dilatation and engorgement of 



