206 MEDICAL BACTERIOLOGY 



agar, ascitic agar and blood serum are made. The organisms most frequently 

 found as the cause of otitis media are the following: staphylococci, bacillus 

 pyocyaneus, streptococci, pneumococcus, bacillus ozena, diphtheria bacillus and 

 bacillus of influenza. 



MASTOIDITIS 



Mastoid infections are usually the result of extension from the middle ear. 

 DISEASES OF THE NOSE 



Primary, secondary and tertiary lesions of syphilis occur occasionally in the 

 nose and are diagnosticated by examination of lesions for treponema pallidum 

 and chiefly by the Wassermann test. 



Diphtheria bacilli may be present in the nose and not elsewhere, in persons 

 not suffering with diphtheria carriers. Nasal diphtheria may occur without 

 the throat being involved; this is rare. 



Chronic rhinitis, chronic nasal catarrh, may be caused by staphylococci, the 

 pneumococcus, bacillus of rhinoscleroma, bacillus of ozena and less frequently 

 micrococcus catarrhalis, meningococcus and other organisms. Any of these 

 organisms may be present at times upon normal nasal mucosa. 



To make a bacteriological examination pass a sterile cotton swab into each 

 nostril, brush it over as much of the membrane as possible, withdraw and make 

 surface plants upon agar, ascitic fluid agar and blood serum. Also prepare 

 slides for microscopic examination. 



When possible it is well to make a second set of cultures and slides after 

 preliminary treatment of the nose as follows: 



Thoroughly cleanse the nose, wash out with sterile salt solution and place a 

 plug of cotton in each nostril so as to filter the air without impairing inspiration, 

 keep the patient in a room free of gas for 12 hours and then obtain material for 

 culture and slides. 



DISEASES OF THE LUNGS 



Bacteriological diagnosis of diseases of the lungs (other than syphilis which is 

 rare) is based upon the microscopic examination of the sputum, occasionally 

 supplemented by cultures from sputum and inoculation of the sputum into 

 rabbits and guinea-pigs. 



The technique for obtaining sputum and examining it has already been con- 

 sidered in the chapters on the pneumococcus and tubercle bacillus. Here it is 

 only necessary to add that pneumonia is not a specific disease. While the 

 pneumococcus is responsible for most cases of acute pneumonia, still, a large 

 number of cases are caused by other organisms, staphylococci, bacillus of 

 influenza, streptococci and the tubercle bacillus. In acute pneumonia, caused 

 by the pneumococcus, that organism is usually found to predominate in the 

 sputum some time during the disease, in nearly all cases, yet it must be remem- 

 bered that occasionally it does not, especially early in the disease. 



It is most important to remember there is a group of cases which start as, 



