Hydrogen- I on Concentrations. 



287 



126 (1873) 



The hydrogen-ion concentrations of joint exudates 

 in acute arthritis. 



By RALPH H. BOOTS and GLENN E. CTJLLEN. 



[From the Hospital of the Rockefeller Institute for Medical Research, 



New York City.] 



The hydrogen-ion concentrations of exudates aspirated from 

 joints of patients ill with acute rheumatic fever and other forms of 

 arthritis were determined. This was done: (1) to compare the 

 reactions of the exudates of the various forms of arthritis; (2) to 

 determine if an acidity existed in inflamed joints of acute rheumatic 

 fever patients sufficient to permit the liberation of free salicylic 

 acid following salicylate therapy. 



Salicylic acid can not exist as such in alkaline solutions; and its 

 salts have not been shown to have bactericidal power in low con- 

 centrations. Although the acid can not exist in normal blood 

 and tissues, their reactions being slightly alkaline, it has been 

 suggested for a number of years that its liberation might occur 

 in the inflamed tissues of patients with acute rheumatic fever; 

 these tissues were supposed to have been under considerably in- 

 creased C0 2 tension. The bactericidal action of this liberated 

 salicylic acid could explain the seemingly specific action of the 

 salicylates on the arthritis of acute rheumatic fever. 



Hanzlik 1 examined exudates from inflamed joints of acute 

 rheumatic fever patients directly for the presence of salicylic 

 acid. The results showed none to be present; but the author 

 offers the criticism that no precaution was taken to prevent the 

 escape of C0 2 . 



In our work, the hydrogen-ion concentrations of all of the 

 exudates were determined colorimetrically at room temperature 

 and corrected to 38 0 C. by a method recently described by Cullen. 2 

 If sufficient fluid was obtained from a joint, the determination 

 was also made electrometrically. With both methods, in order 



1 Jour. Pharm. and Exp. Therapeutics, 1917, ix, 217. 



2 Jour. Biol. Chem., 1922, 1, 17. 



