In the work detailed in this thesis a bacteriological investigation has been made of the three conditions of cholecystitis, appendicitis and peptic ulcer. This was originally undertaken with the', .object of confirming the work of Rosenow in this direction. On the whole, it may be said that his general findings with regard to the nature of the
organisms isolated and their presence within tissues has been supported, though a somewhat different incidence has been found which may possibly be due to differences in the type of material examined. Special attention has been paid to the biological characters of the organisms isolated, especially the streptococci, with the object of determining the site of their
origin in the body. It has been found that in cholecystitis the organisms present are predominantly of a character similar to those found normally in the bowel. In peptic ulcer less evidence has been available, but on the whole, mouth types of organisms seem to be more frequent.No evidence has been found of any tendency towards "elective localisation" of the organisms isolated. Cholecystitis may be produced relatively easily in rabbits by intravenous injection of coliform organisms, but such action seems to be entirely non-specific, and to occur as readily with organisms
isolated from other lesions as with those isolated from cases of cholecystitis. Animal experiments suggest that infection reaches the gall -bladder either through the systemic circulation or by descending infection from the liver in the bile, though in exceptional circumstances it may travel by other routes. Lesions in the appendix have not been produced to any extent with organisms in the present work. Haemorrhages in the stomach and duodenum have been found with great frequency in experimental animals after the intravenois injection of organisms, but it does not seem
justifiable to draw any conclusions from these findings
as regards the aetiological relationship to peptic ulcer in man of the organisms injected.No evidence has been found so far that in the
human subject infection is the primary factor in the
production of cholecystitis and gall stones. In the
'early stages of cholecystitis organisms are found with
!difficulty, but the incidence rises as complications,
such as the formation of stones and the presence of
obstruction, occur. In the syndrome of acute
obstructive cholecystitis the presence of a secondary
anaerobic infection is of great practical importance.
It is possible that the organisms isolated in this
condition may all play the part of secondary invaders
when once some change, toxic or biochemical, has
already commenced in the biliary tract.In appendicitis, the primary factor is probably a dietetic one, and the evidence is strongly in favour of this condition being a disease of civilisation. A decreased consumption of cellulose and an increased consumption of protein seem to be the important factors, and they probably act by the encouragement of stasis and the production of catarrh in the appendix, with the passage of organisms through the
mucous membrane. In the vast majority of cases the
!infection in appendicitis is undoubtedly an enterogenous
one, though rarely it may be a haematogenous one arising in some distant focus such as the tonsils. Anatomical factors, such as the position of the appendix and the nature of its blood supply, probably play an important part in the progress of the inflammation. As the inflammation progresses, the incidence and virulence of the organisms present in the appendix rises, and this is specially the case
with the anaerobic flora. In obstructive and gangrenous conditions it is the anaerobes which are mainly responsible for the complications and mortality.In the case of peptic ulcer, the evidence is perhaps a little stronger that infection, usually with streptococci, is the primary factor responsible. Once ulceration has occurred, a vicious circle becomes ;established, and a secondary infection may be added. Whether infection originates or maintains the condition, however, its importance is such as to render absolutely necessary in treatment the eradication of all septic foci in the abdomen and elsewhere. In recent years since the "pathology of the living's has been more extensively studied, considerable stress has been layed on the relationship of these three conditions, which have been referred to by Wilkie as the "abdominal triad ". There is definite clinical evidence that in some cases they are related, and that the appendix provides the original focus.
In the present work, material from too few cases in which all three lesions have been treated surgically has been examined to justify any conclusion on the nature of the infection present. Till our knowledge about the origin and pathway of infection in these conditions is more definite, however, and till we have determined what is the primary factor, dietetic or otherwise, that allows infection to occur, our therapeutics must continue to rest on the principle
that the infection is implanted within the tissues of
the organ diseased, and that unless natural resolution
can be shown to occur, the continuation of the infection and its spread to other organs can only be prevented by surgical treatment
