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APPENDIX II.
LABORATORY NOTES.
By Civil Assistant Surgeon T. Sitapati Ayyar, I.M. S.
Note I .—Attempts to isolate B. Typhosus or any other organism of the Gærtner group from
peripheral blood have been made over a dozen times during the year without any success, the
method adopted being the one recommended in circular No. 735-1 (PMOs) of 17th February
1911, in which 5 c.c. of blood is inoculated into sodium taurocholate water medium and
incubated. A few laboratory experiments regarding the efficacy of the method were conducted
with the result that the medium was shown not to be at fault.
Note II .—The examination of material from macerated foetuses was continued during the
year. A table of 40 such specimens is appended to the report. Unlike the last year, the results
compare favourably with the other years about 25 per cent of the specimens showing positive
findings. During the latter part of the year arrangements were made to examine the bloods of
the mothers for the Wassermann reaction. A higher percentage of the bloods of the mothers
gave a positive Wassermann reaction than sections of the fœtal livers showed spirochætes.
Finer methods would have to be employed and a very large number of sections examined from
each liver to make certain of detecting the spirochetes in every still born foetus derived from a
syphilitic mother.
Note III— A paper regarding the use of salt in preserving the bacterial flora of water
samples unchan ged during transmission to a distant laboratory was read by Military Assist-
ant Surgeon E.C. R. Fox of Kasauli at the Sanitary Conference of 1912. Further experiments
were made in this laboratory to find if this plan would suit the conditions met with in this
Presidency. If successful, it would minimise the expenditure incurred in bringing samples from
different parts of the Presidency to the laboratory. The original experiments conducted by
Remlinger were also studied. The method employed in this laboratory was to add sodium
chloride to samples of water in the proportions of 3 per cent., 4 per cent. , 5 per cent., 6 per
cent. and 8 per cent. and to keep them at room temperature (85° to 95°F) for two days. The
results were compared with those obtained by the immediate examination of other portions of
the original samples. It was found that there was a very large increase in the total number of
colonies growing on agar and in lactose fermenters (fœcal organisms) when the added salt
amounted to 5 per cent. and less. The higher percentages, namely, 6 and 8, not only prevented
multiplication of the bacteria but even caused an appreciable reduction in the number of
colonies found on the plates. Salting therefore does not preserve unchanged the bacterial flora
of water samples in the plains and cannot be utilised in place.of the ordinary system of collection
and transmission.
Note IV—Wassermann test .—During the year there was an increase in the number of
specimens of blood examined for Wassermann reaction, 680 against 481 of the previous year.
A certain number of bloods were collected and tested for experimental purposes. Of these 382
were examined by both the methods, Original and Levaditi's modification, to arrive at the
comparative value, while the remaining were subjected to the modification only due to the want.
of the spirochete livers in the early part of the year.
Regarding the technique of the tests employed, there has not been much in the way of
alteration. The desiccation of the liver substance is now achieved by a more rapid but still
unsatisfactory method of putting it over pure sulphuric acid in a bell-jar from which the air is
exhausted by an air-pump. This method prevents the onset of the putrefactive changes that
always accompany the slow method of desiccation in a closed vessel over quick-lime. The antigen
used in both the methods is rendered more powerful by making the extract from several speci-
mens mixed together, to enable it to have the effect of a polyvalent material. The amount of
compliment hitherto in use has been reduced to one volume of 60 per cent. dilution against one
volume of the strong guineapig serum. It has also been found that the rabbit's hæmolytic
serum against sheep cells, loses its hemolytic power rather quickly so that the serum has to be
frequently tested to find. out the amount of dilution which is necessary to lyse red. blood cells.
The superiority of the original method over the modification can be inferred. on comparing-
the results of the different methods of Wassermann test in the clinically diagnosed cases at
various stages of the disease. In 82 primary cases the modification method was used with the
result of positive finding in 17 per cent, only, while in 57 cases where original method wns
employed there was a positive finding in 59 per cent. In the secondary form 118 bloods were
tested by the modification with 57 . 6 per cent. positive and 71 by the original with 73 per cent,
positive reactions. In the tertiary, the modification gives positive reaction in 43 . 5 per cent.
while the original in 65 per cent, cases. In nervous forms attributed to syphilis as para
o r m e t a
S y p h i l i t i c l e s i o n s , 6 0 p e r c e n t . o f p o s i t i v e r e s u l t w a s o b t a i n e d b y t h e o r i g i n a l m e t h o d
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