INDEX OF INFECTIOUS DISEASES. 681 



ause of pleurisy in children and of metapneumonia pleurisy, but 

 that in metastatic, pyogenic, pleuritic inflammation the strepto- 

 coccus or staphylococcus are the common infective agents. Pleurisy 

 due to streptococcus or staphylococcus infection is not in all cases 

 attended with pus formation ; the exudate in a certain proportion of 

 cases may remain serous. 



In pleurisy occurring as a complication of typhoid fever the 

 bacillus typhosus has been found in the exudate. Occasionally 

 bacillus coli communis has been found. According to Flemming, 

 about 41 per cent, of the fatal cases of pleurisy are due to tubercular 

 infection. 



Pleuropneumonia of Cattle. Due to infection by the pneumo- 

 bacillus liquefaciens bovis of Arloing. 



Pneumonia. Characteristic lobar pneumonia is due to infection 

 by the pneumococcus, 507, 511 ; irregular cases are usually due to 

 Friedliinder's bacillus, streptococcus, staphylococcus, typhoid bacil- 

 lus, and influenza bacillus, 325. 



Puerperal Fever. Due usually to infection by streptococcus, 

 482, or colon bacillus, 453. In some fatal cases staphylococcus 

 pyogenes aureus has also been found. Among other micro-organisms 

 sometimes met with, and which in these cases may have been con- 

 cerned in the production of the inflammatory process, are gonococcus 

 and proteus vulgaris. 



Purpura Hsemorrhagica. No micro-organism has been shown 

 to be specific for this affection. 



Pyaemia. (See Septicaemia.) 



Pyelonephritis. According to Schmidt and Aschoff (1893), 

 pyelonephritis or surgical kidney is an infectious process usually due 

 to bacillus coli communis. (See also Nephritis. ) 



Pyosalpinx Zweifel ( 1 892 ) has shown that a certain proportion 

 of the cases of pyosalpinx, if not all of them, are due to the pres- 

 ence of the gonococcus, 528. In some cases the infectious agent is 

 apparently streptococcus pyogenes or pneumococcus ; but Zweifel 

 believes that in the majority of cases in which the gonococcus is not 

 found it is the infectious agent, its absence being due to the fact that 

 it has died out in cases examined too late to find it. 



Relapsing Fever. Due to infection by spirillum Obermeieri, 

 596. 



Rheumatic Fever. The close analogy existing between true 

 rheumatism and certain of the infectious diseases, such as gonorrhoaa, 

 scarlet fever, and septic processes in general, which are frequently 



