220 ACTIVE IMMUNIZATION 



in 55.07 per cent. Considering the advanced character of the lesion 

 in these individuals, this is indeed quite remarkable. 



If we contrast these findings with the results of a purely expectant 

 (sc., hygienic-dietetic) plan of treatment, where only 20 per cent, 

 of the cases show loss of bacilli, no further argument in favor of the 

 tuberculin treatment is required. It should be remembered, more- 

 over, that the actual results were probably still better than is sug- 

 gested by the above figures, if we consider that the improvement 

 continues for three or four months after the treatment is suspended. 

 They might have been still better, as Bandelier suggests, if the limit 

 of immunization, i. e., the maximal dose of tuberculin had been 

 higher than 10 milligrams, which had been chosen as standard. 



Of late, systematic efforts have been made to improve the hygienic 

 condition of the tubercular poor, and to give these also the benefit 

 of the tuberculin treatment when living in their own homes. As a 

 consequence the outlook for these unfortunates has been materially 

 improved. Friedrich thus records that of 700 cases of early tuber- 

 culosis which were treated in this manner the disease w r as arrested 

 or the patients much improved in 51 per cent, of the cases. Similar 

 results have been reported from other sources. 



ESTIMATION OF THE OPSONIC CONTENT OF THE BLOOD 

 (WRIGHT'S METHOD). 



Before concluding this chapter it may not be out of place to give 

 a brief account of the technique which Wright recommended for 

 the purpose of estimating the opsonic index, but which at present 

 has but little more than historical interest, insofar as its bearings on 

 treatment or diagnosis are concerned. The necessary apparatus is 

 pictured in the accompanying illustration (Plate III). It consists 

 of a pipette (a) for collecting corpuscles; (6) a tube to receive the 

 blood to be examined, in place in which the blood capsule (c) can 

 also be used; and capillary pipettes (d and e) provided with rubber 

 nipples. For purposes of incubation a special thermostat is recom- 

 mended, but in its absence the usual laboratory incubator may be 

 employed. The actual "reagents" are represented by the patient's 

 serum, a normal control serum, washed leukocytes, and bacterial 

 emulsions. 



