SIMPLE INFECTIONS 97 



serofibrinous pleuritis with a temperature rising to 38.8° C. and 

 remittent in type. 



With simple exudative or catarrhal inflammation, there is usually 

 no or but slight leucocytosis. DaCosta states that in 45 cases of 

 simple appendicitis without pus, gangrene or peritonitis less than 

 nine per cent, had a leucocyte count of more than 15,000, the 

 maximum was 17,100, the average 8,987. 



With purulent inflammations the changes in the blood are as a 

 rule more marked. The red corpuscles may show slight or marked 

 decrease. With local suppuration in wounds, empyema, and so 

 on, there is usually but slight or no change except in long standing- 

 cases. Red corpuscles show diminution so long as the discharge 

 continues. Fibrin is increased in cases with suppuration (Cabot). 



In cases of septicemia there is usually a rapid loss of red cor- 

 puscles. The hemoglobin is ordinarily more affected than the 

 number of red corpuscles. The leucocytes as a rule show a marked 

 increase, the increase affecting the polymorphs mainly. In a cer- 

 tain class of cases it should be borne in mind that the leucocytes 

 may show a decrease. These are very severe cases, those in which, 

 owing to the virulence of the infecting organisms or the lack of 

 resistance of the individual, the leucocytic reaction does not occur. 

 In such cases the loss in leucocytes is in the polymorphs. The 

 iodine reaction often gives valuable aid in septic cases with leuco- 

 penia, glycogenic degeneration being often present. Locke and 

 Cabot state "no septic condition of any severity can be present 

 without a positive reaction." Barnicot does not consider that 

 the reaction should be given so much value as this; but states that 

 "when accumulation of pus is suspected the absence of the re- 

 action is of very great negative value." 



When an abscess becomes walled off or ceases to spread the 

 leucocytes decrease slowly; with opening or evacuation of the 

 pus the leucocytes promptly decrease if there is free drainage. 

 With the formation of pockets of pus the number rises again. 

 This was well shown in the case of a horse with shoulder abscess. 

 Operations to secure complete drainage were made every few days 

 extending over a considerable time. The formation of new pockets 

 of pus was shown clearly by the leucocyte count. After drainage of 

 the pus that had formed, the leucocyte count promptly decreased, 

 only to rise again after a day or two due to the formation of other 



