582 ELECTIVE LOCALIZATION OF BACTERIA 



teeth are extracted under as nearly sterile conditions as possible, and, in special in- 

 stances, the apical end is resected for culture before the tooth is extracted. Culture 

 controls are made of the mucous membrane before and after sterilization, and of the 

 overlying bone after the mucoperiosteal flap is resected. 



ELECTIVE LOCALIZATION FOLLOWING INTRAVENOUS INJECTION 



Many diseases have been studied from the standpoint of elective localization ac- 

 cording to the procedures and methods herein described. Much valuable knowledge 

 as regards the etiology and management of previously poorly understood and closely 

 related diseases, as well as of epidemic diseases, has been revealed. Streptococci that 

 localized and produced lesions electively in the tissues or organs of animals injected 

 intravenously corresponding to those affected in the patient were isolated from one or 

 more foci of infection or from systemic lesions, or both, with great regularity. These 

 reports have been published chiefly in the Journal of the American Medical Associa- 

 tion and the Journal of Infectious Diseases during the last ten years. They concern 

 the following diseases: appendicitis, ulcers of the stomach and duodenum, chole- 

 cystitis, pancreatitis, epidemic parotitis, acute and chronic arthritis and myositis, 

 acute iritis and allied diseases of the eye, erythema nodosum, herpes zoster and neural- 

 gia, neuritis and sciatica, transverse myelitis, and poliomyelitis. 



The incidence of lesions in the specific organ or tissues in the observations re- 

 ported varied from 60 per cent in cases of ulcer of the stomach to 90 per cent in those 

 of erythema nodosum. Control animals injected with streptococcus strains from pa- 

 tients suffering from miscellaneous diseases or from persons without systemic disease 

 failed to show specific localizations. Specific localization of the streptococcus often 

 occurred despite the fact that often there were few other bacteria in the cultures in- 

 jected. It may be that localization of the streptococcus was favored by growth in 

 symbiosis with these organisms, but the latter were usually not found in cultures or 

 on microscopic examination of the affected tissues. However, elective localization of 

 mixtures of bacteria has been observed. Thus, in a case of acute appendicitis in which 

 the attack followed closely Vincent's angina, mixtures of streptococci and fusiform 

 bacilh were isolated from the throat and extirpated appendix, and both produced 

 marked lesions of the appendix. Cultures from the lesions in the appendix again re- 

 vealed the mixtures, and fusiform bacilli and streptococci were found in the lesions 

 in stained sections. Colon bacilli with respective localizing power were isolated in a 

 few cases of acute cholecystitis and appendicitis; and, in one case each of acute chole- 

 cystitis and pancreatitis, a staphylococcus was isolated which localized electively on 

 intravenous injection into animals. A striking instance of elective localization of a 

 staphylococcus in the kidney occurred in a case of severe nephritis in which the pri- 

 mary mixed cultures of this organism and streptococcus from an infected maxillary 

 sinus and from tonsils were injected intravenously. 



The results of elective localization following intravenous injection have been fully 

 corroborated and extended in important respects by my co-workers in the laboratories 

 of the Mayo Foundation, as well as by independent investigators. Meisser' has re- 

 ported coniirmatory results in a long series of experiments with streptococci isolated 



' Mcisscr, J. G.: J. Am. Dent. A., 12, 554. 1925. 



