1 104 CHEMOTHERAPY OF BACTERIAL DISEASES 



locally infected by an organism, as, for example, the urethra by the gonococcus; but 

 in relation to chemotherapy, it may also include a tissue or organ infected by way of 

 the bloodstream but yet treatable by the local application of a medicament to the 

 infected parts — for example, a joint may be infected by a streptococcus conveyed in 

 the blood from the apical abscess of a tooth but be amenable to treatment by the local 

 injection of a chemical disinfectant. Infections of the skin, the accessory sinuses of 

 the upper respiratory tract, gums, conjunctivae, urethra, bladder, etc., are usually 

 localized infections in the strict sense; but pleuritis, meningitis, and infections of other 

 serous cavities may be also classified as localized infections from the chemothera- 

 peutic standpoint since they may be treated by direct local or topical application or 

 injection of disinfectant substances even though the organisms are brought to the 

 parts by systemic channels. On the other hand, certain infections of other organs as 

 those of the iris, gallbladder, perirenal tissues, etc., may be strictly localized but 

 reachable therapeutically only by way of injection of medicaments directly into the 

 blood or indirectly by absorption from the subcutaneous tissues, muscles, or gastro- 

 intestinal tract. 



In other words, generalized or systemic infections are those in which organisms 

 occur constantly or intermittently in the blood or lymph streams with one or several 

 localizations in the fixed tissues; usually they are treatable only by way of the lymph 

 or blood streams by direct injection of medicaments into the blood or absorption from 

 the subcutaneous tissues, muscles, or gastro-intestinal tract. Localized infections are 

 those in which the organisms occur in the infected parts as the result of a direct in- 

 fection or by localization of organisms from the blood; according to accessibility of 

 the part infected they may be treated by the topical application or systemic adminis- 

 tration of drugs. 



ESSENTIAL PROPERTIES OF A CHEMICAL AGENT FOR THE CHEMOTHERAPY 

 OF LOCALIZED BACTERIAL INFECTIONS BY TOPICAL APPLICATION 



1. They must possess some degree of bactericidal and bacteriostatic activity in the test 

 tube and tissues and especially in the presence of serum, blood, pus, etc. These effects 

 need not be extremely high, and they may be selective, as, for example, gentian 

 violet and other dyes of the triphenylmethane series for gram positive bacteria like 

 staphylococci, streptococci, pneumococci, diphtheria bacilli, etc. While an extremely 

 high bactericidal or bacteriostatic activity in vitro is not essential, yet it is desirable, 

 as such a compound is more likely to retain effective degrees of bacteriostatic activity 

 in vivo, although a chemical agent possessing a high degree of selective bacteriostatic 

 power may fail in the treatment of a mixed infection. 



2. In addition they shoidd possess the property of destroying toxins, and especially 

 the toxins of the tetanus and other anaerobic bacilli of infected wounds; in this con- 

 nection it may be stated that the oxidizing disinfectants, as those of the chlorin 

 group, are believed to have this property. 



3. They shoidd not be precipitated or their bactericidal properties neutralized by the 

 proteins or salts of the polybasic acids of the body fluids and tissues with which they come 

 in contact, as by pus and necrotic tissues in wounds or serous cavities, by urine in the 

 pelvis of the kidney or bladder, etc. 



