PART IV. 



CLINICAL BACTERIOLOGY AND ANIMAL PARASITOL- 

 OGY OF THE VARIOUS BODY FLUIDS AND ORGANS. 



CHAPTER XXII. 



Diagnosis of Infections of the Ocular Region. 



IT is advisable before taking material for cultures or smears to 

 cleanse the nasal area of the eye-lids, and especially about the carun- 

 cles, with sterile salt solution. Then, by gently pressing on the lids, we 

 may be able to get pure cultures of the organism causing the infection. 

 Normally, we may find in the region of the caruncles various skin 

 organisms, especially staphylococci, giving white colonies. 



A small particle of sterile cotton, wound on a toothpick, with the 

 aid of a sterile forceps, makes an excellent swab for obtaining material 

 for smears; the same may first be drawn over an agar surface in a 

 Petri dish in a series of parallel lines of inoculation before making the 

 smears on slide or cover-glass. 



When there is considerable discharge, a capillary pipette, with a 

 rubber bulb, may be used to draw up sufficient material for cultures 

 and smear. Be sure to round off the end of the pipette in the flame 

 and not to use a very fine capillary tube. 



In conjunctival tultures, plates of glycerin agar or agar plates 

 smeared with blood are to be preferred, as the gonococcus and Koch- 

 Weeks bacillus will only grow on blood or hydrocele agar. The 

 diphtheria and xerosis bacilli grow well on glycerin agar. 



In addition to the white staphylococcus, the streptococcus may be 

 present when inflammation of the nasal duct exists. 



The pneumococcus is a fairly common cause of serpiginous corneal 

 ulcerations. Active treatment is necessary. 



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