PNEUMOCOCCUS. 61 
and such cases usually recover without resection of ribs. 
The bacteriological examination of the pus from a 
pleural cavity may thus lead to results important as 
to prognosis and treatment. 
4. The pneumococcus may occur as a secondary in- 
fection in almost any disease of the lung; for instance, 
in the walls of a phthisical vomica. 
The most important primary lesion due to the pneu- 
mococcus outside the respiratory system are :— 
1. Otitis media, of which it is a very common cause. 
2. Brawny induration of the skin with or without sup- 
puration. This is uncommon, but the author has seen 
several cases. 
Pneumococci may escape into the blood from any of 
these lesions, and may appear in that fluid when there 
is no obvious primary lesion from which it could have 
gained access. The most common results are :— 
1. Septicemia. 
2. Ulcevative endocarditis. Many other bacteria may 
cause this disease. 
3. Meningitis. Pneumococcal meningitis may also be 
due to direct spread from the middle ear. 
4. Arthvitis. 
5. Peritonitis. 
In actual practice we have most commonly to search 
for the pneumococcus in sputum, pus, and blood. In 
the latter case cultural methods are usually necessary, 
and we shall defer its consideration for the present. 
Sputum.—The examination of sputum may be made 
in order to make a diagnosis as to the presence or 
absence of pneumonia in a case in which the physical 
signs are indeterminate, or to establish the nature of a 
lobular pneumonia. 
The patient must wash out his mouth with water, 
