22 
There are several interesting points that come out of the above 
results. The first is that acid-fast bacilli were found only once in 
smears made from the blood of the 48 cases of human tuberculosis, 
although the bacilli had been demonstrated in the sputum of 47 of 
them. In the one case (case Xo. 1) acid-fast bacilli were not found 
in the centrifugalized sediment, but were found in the sediment of the 
citrated blood that had remained in the ice chest over ni^ht. 
The question is, TTere these acid-fast bacilli tubercle bacilli ? If so, 
why did they not grow on cultures and infect guinea pigs? I must 
confess that I am unable to answer these questions, but am inclined 
to the opinion that they were not tubercle bacilli for the following 
reasons : The acid-fast bacilli were present in the smears in such num- 
bers as to be seen in practically every field; they were most frequently 
seen in clumps consisting of 3 to 30 or more bacilli; most of the indi- 
vidual bacilli were shorter than the usual type of human tubercle bacilli. 
Xow, the smear was made from one large drop of the citrated sedi- 
ment and from the numbers seen in the portion of the slide examined 
there must have been many hundreds of bacilli in each drop of the 
sediment. Five drops of the same sediment were planted on glycerin 
potato, but no growth resulted, and 2.5 c. c. of the same sediment was 
inoculated into a guinea pig (guinea pig Xo. 2), but with negative 
results for tuberculosis. These amounts were many times that used 
to make the smear and, of course, must have contained a great many 
more bacilli; but tubercle bacilli were not demonstrated by cultures 
or animal inoculation. 
As mentioned before, the acid-fast bacilli were not found in the 
smears made from the centrifugalized sediment . The case from which 
the blood was taken was in a very early stage and was improving at 
the time the blood was taken; had no fever, no night sweats, very 
slight cough, and was gaining in weight, but still had bacilli in the 
sputum at that time. 
His occupation being that of a stableman, and being employed as 
such at the time the blood was taken, might suggest a possible con- 
tamination of the blood with an acid-fast grass or hay bacillus on the 
skin, which developed in the citrated blood in the ice chest over night 
and was found in the smears made from the sediment. This possi- 
bility emphasizes the great care necessary to avoid the entrance of 
acid-fast bacilli from any source, such as the skin, air, water, and citrate 
of soda, etc., into the blood when it is drawn, and is, perhaps, in har- 
mony with the latter part of Bergeron’s conclusions. 
The second point is, that in my hands the imding of tubercle bacilli 
in smears made from the blood of known cases of tuberculosis on ac- 
count of almost uniformly negative results seem to be of little value as 
an aid in the diagnosis of tuberculosis. These negative results could 
not have been due to the tubercle bacilli being overlooked, for all the 
