COMPOSITION OF EFFUSIONS 

 Table I 



353 



Parts per 100 ot fluid 



Sp. gr. 



Total 

 protein 



Fibrin 



Serum- 

 globulin 



Serum- 

 albumin 



Acute pleurisy . . . 

 Acute pleurisy. . . 

 Acute pleurisy . . . 



Hydrothorax "1 

 Aver, of 3 cases / 



1.023 

 1.020 

 1.020 



5.123 



3.4371 



5.2018 



0.016 



0.0171 



0.1088 



3.002 



1 . 2406 

 1.76 



2.114 



1.1895 



3.330 



1.014 



1.7748 0.0086 



0.6137 



1.1557 



The specific gravity varies nearly in direct proportion to the amount 

 of proteins, that of transudates usuall}^ being below 1.015, and exu- 

 dates above 1.018, although there are many exceptions. Indeed, it is 

 often very difficult to decide whether a given fluid is an exudate 

 or a transudate. ^^ According to Rzentkowski,^^ the transudates at 

 the moment they pass out of the vessels are simply solutions of crystal- 

 loids in water and quite free from protein; the small amount of protein 

 found in transudates he ascribes to protein pre-existing in the tissue- 

 spaces. This idea is hardly acceptable in view of the known per- 

 meability of the vessel-walls for proteins in normal conditions; more 

 probably in cardiac and renal dropsies the quantity of protein escap- 

 ing from the vessels is not greatly different from normal, but the 



68Rivalta (Rif. Med., 1903; Biochem. Centr., 1904 (2), 529) has suggested 

 the following test to distinguish exudates and transudates: Into a beaker con- 

 taining 200 c.c. of water with 4 drops of glacial acetic acid, let fall a few drops 

 of the fluid to be tested. If an exudate, a bluish-white line is left transiently 

 behind the sinking drops, due to precipitation of the euglobulin and fibrinogen. 

 This test, and also certain modifications (see Rivalta, Policlinico, 1910 (17), 

 676), seem to give quite reliable results. (See Ujihard, Berl. klin. Woch., i914 

 (51), 1112). With tuberculous effusions Rivalta's test is positive, but not Mo- 

 relli's test, which consists in dropping the fluid into saturated HgClo solution, a 

 yellowish ring of albuminate forming with non-tuberculous exudates, and a gran- 

 ular precipitate with transudates. (See Zannini, Gaz. degli Osped., 1914 (4), 

 461). Memmi (Clin. Med. Ital., 1905, No. 3) suggests the larger content of 

 lipase as a means of distinction of exudates. Tedeschi (Gaz. degli Osped., 1905 

 (26), 88) states that egg-albumen fed in large amounts appears in transudates 

 and not in exudates, and can be detected by the biological precipitin test. Sugar 

 is found more often in transudates (Sittig). 



" Virchow's Arch., 1905 (179), 405. 



23 



