PART IV. 



CLINICAL BACTERIOLOGY AND ANIMAL PARA- 



SITOLOGY OF THE VARIOUS BODY 



FLUIDS AND ORGANS 



CHAPTER XXIII. 

 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 caruncles, 

 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. 



The xerosis bacillus and white staphylococci may be considered normal findings 

 in the conjunctival sac. Streptococci and pneumococci have also been reported 

 from apparently normal conjunctival secretions. 



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 in- 

 oculation 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 smears. Be sure to 

 round off the end of the pipette in the flame and not to use a very fine capillary 

 tube. 



In conjunctival cultures, plates of glycerine 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 

 glycerine agar. 



In addition to the white staphylococcus, the streptococcus may be present 

 when inflammation of the nasal duct exists. 



The Streptococcus is at times responsible for a pseudo-membranous conjunctivi- 

 tis. The Staphylococcus is as a rule the cause of phlyctenular conjunctivitis. 



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