DIAGNOSIS 207 



run the typical course of, and are clinically diagnosticated as acute lobar pneu- 

 monia caused by the pneumococcus ; that bacteriological examination of the 

 sputum prior to crisis shows a preponderance of pneumococci in most cases and 

 seldom shows tubercle bacilli; that after crisis recovery does not follow, cough 

 and expectoration continues, resolution is incomplete, the sputum may still 

 show a preponderance of pneumococci, but usually many organisms are present, 

 tubercle bacilli are not discovered for weeks or months; prior to their discovery 

 it becomes obvious that the case is one of pulmonary tuberculosis. In all such 

 cases where resolution and convalescence are retarded following crisis a tuber- 

 culin test should be made. 



DISEASES OF THE GASTRO -INTESTINAL TRACT AND CONTINUOUS FEVERS 



The signs, symptoms and clinical course of typhoid fever, paratyphoid 

 fever, food-poisoning, tuberculosis, syphilis, gonococcus, staphylococcus and 

 streptococcus infections and malaria are at times indistinguishable, except by 

 careful bacteriological studies. 



In typhoid, paratyphoid, colon bacillus and other infections caused by 

 members of the typhoid-colon group, during the first week of the disease the 

 offending organism can always be isolated from the blood by culture. Later 

 than the second week the offending organism or its specific agglutinin can be 

 found in the blood in nearly all cases. These tests should be made in all such 

 cases, and when negative, foci of infection with pyogenic cocci should be sought 

 for; blood cultures for staphylococci, streptococci and pneumococci should be 

 made. If these fail to establish the diagnosis the Wassermann and possibly 

 the gonococcus complement fixation tests should be made. 



In suspected cases of cholera and bacillary dysentery the feces should be 

 examined by culture for the offending organism and the blood serum for specific 

 agglutinin and lysin. 



Huston and McCloy, The Lancet, vol. ii, No. 15, Oct. 7, 1916, have reported 

 the isolation of an organism, called " enterococcus " from the feces of patients 

 with a cryptogenic illness, which they believe is due to this organism. They 

 believe the "enterococcus" is not of the normal bacterial flora of the intestine 

 and suggest the advisability of attempts to isolate possible causative organisms 

 from the feces in all cases of cryptogenic gastro-intestinal disease. 



DISEASES OF THE GENITO -URINARY TRACT 

 ULCERS OF THE EXTERNAL GENITALIA 



Ulcers of the external genitalia may be due to physical, chemical or vital 

 causes. Any of the organisms that produce ulceration of the skin elsewhere may 

 do so here. As a matter of fact, nearly all the ulcers of the external genital 

 organs that are brought to the bacteriologist for diagnosis are chancres or 

 chancroids, the result of venery, and the problem is to discover whether they 

 are caused by the treponema pallidum or other organisms. 



The technique of examination is as follows: Thoroughly cleanse the ulcer 



