14 QUATERCENTENARY STUDIES IN PATHOLOGY 



pleural cavity was then aspirated and a large quantity of pus containing 

 pneumococcus withdrawn. In spite of this, the patient died with an 

 index above normal. In the other case the opsonic index rose to i'5, 

 but on opening the pleural cavity it fell to normal and healed quickly. 



The amount of opsonin present in the serum and exudate in post- 

 pneumonic empyaema was examined in four cases. Case i gave an 

 opsonic index of i'4. Twenty-two ounces of pus were aspirated from 

 his chest (pure culture of pneumococcus). The opsonic index of the 

 liquor puris compared with the blood serum was o, the leucocytes refusing 

 to pick up a single coccus. Two days later the empyaema was drained ; 

 the blood-serum at time of operation had opsonic index of i'35, and the 

 liquor puris of the exudate 0'5. Next day, that of the serum was 1*37, 

 and of the exudate i '36. The progress of the case was rapid, the opsonic 

 index of the serum and fluid of the exudate were tested successively 

 for ten days, and both adjusted themselves gradually till both were 

 approximately normal. The exudate always gave a slightly lower 

 reading than the blood-serum. The blood-serum of Case 2 gave an 

 opsonic index of ri on the day subsequent to draining operation on his 

 pleural cavity, while the exudate gave an index of 099. The infection 

 was a pure pneumococcus one, and the discharge ceased within a week. 

 Case 3 was a child, and fatal. Along with pneumococcus. Staphylococcus 

 albus was present. Two days before death the opsonic index of the serum 

 was 1*2, and that of the exudate 0"3. Case 4 had a discharging empysema, 

 subsequent to pneumonia, for two years. The organisms isolated were 

 Bacillus coli^ Staphylococcus albus, etc. The opsonic index of the serum 

 of the blood was 0*55, and that of the discharge 0*52. Treatment by 

 continuous negative pressure was continued for two months, during 

 which he improved greatly. At the end of the time the opsonic indices 

 in the blood-serum and exudate fluid were i*o8 and 0*85 respectively. 



The seventeen cases definitely diagnosed as broncho-pneumonia came 

 from the children's wards. These were similarly tested with pneumococcus 

 and their indices determined. The results in these cases are very much 

 less definite than in genuine croupous pneumonia in adults. In some of 

 the cases with a high temperature and signs of a severe infection the 

 opsonic index was normal throughout. In most of the cases the results 

 are so varying that a definite curve for the course of opsonin in this 

 aflection could not be attempted. Of the nine cases in children diagnosed 



(378) 



