Abstract
The numbers of colonies of Candida albicans which develop resistance to 5-fluorocytosine on 50% serum agar are significantly lower than those developed on 50% urine and Wickerham's agar media. Serum induces the hyphal growth form which is characterised by the presence of resting nuclei. There were fewer mitoses in the myeelial phase than in blastospore multiplication, and it is concluded that the rate of acquisition of resistance to 5-FC is related to this. The minimum fungistatie concentration of 5-FC for C. albicans is less in serum than in urine.
In the treatment of urinary Candida infections, the emergence of isolates with total resistance to 5-FC in the urine is not necessarily a sign that the patient will fail to respond to therapy, since much of the fungistatic effect on the fungal colonisation in the tissue may still persist.