CONJUNCTIVITIS 



219 



contagious conjunctivitis, especially prevalent in Egypt, but also 

 common in this country. This organism is very minute, being 

 little more than 1 /u, in length, and morphologically resembles 

 the influenza bacillus ; its conditions of growth are even more 

 restricted, as it rarely grows on blood agar, the best medium 

 being serum agar. On this medium it produces minute tran- 

 sparent colonies like drops of dew. The obtaining of pure 

 cultures is a matter of considerable difficulty, and it is nearly 

 always accompanied by the xerosis bacillus. It can readily be 

 found in the muco-purulent secretion by staining films with weak 

 (1 : 10) carbol-fuchsin, and is often to be seen in the interior 

 of leucocytes (Fig. 54). 

 Another organism exceed- 

 ingly like the previous, 

 apparently differing from 

 it only in the rather wider 

 conditions of growth, is 

 Miiller's bacillus. It was 

 cultivated by him in a 

 considerable proportion of 

 cases of trachoma, but its 

 relation to this condition 

 is still a matter of dis- 

 pute. Another bacillus 

 which is now well recog- 

 nised is the diplo-bacillus 

 of conjunctivitis first de- 

 scribed by Morax. It is 

 especially common in the 

 more subacute cases of 

 conjunctivitis. Eyre 

 found it in 2 - 5 per cent. 



of all cases of conjunctivitis. Its cultural characters are given 

 below. The xerosis bacillus, which is a small diphtheroid 

 organism (Fig. 118), has been found in xerosis of the con- 

 junctiva, in follicular conjunctivitis, and in other conditions ; 

 it appears to occur sometimes also in the normal conjunctiva. 

 It is doubtful whether it has any pathogenic action of importance. 

 Acute conjunctivitis is also produced by the pneumococcus, 

 epidemics of the disease being sometimes due to this organism, 

 and also by streptococci and staphylococci ; the staph, albus may, 

 however, often be found in the conjunctival sac when there 

 is little or no evidence of inflammation. True diphtheria of 

 the conjunctiva caused by the Klebs - Lbffler bacillus also 



Fig. . r i4. — Film preparation from a cise of 

 acute conjunctivitis, showing Koch-Weeks 

 bacilli, chiefly contained within a leucocyte. 



(From a preparation by Dr. Inglis Pollock. ) 

 x 1000. 



