Flucytosine monotherapy for cryptococcosis

Clin Infect Dis. 1998 Aug;27(2):260-4. doi: 10.1086/514669.


Flucytosine (5-FC) monotherapy for cryptococcosis is not advocated because drug resistance emerges during therapy. Reported documentation of this widely accepted belief is surprisingly scarce. Therefore, we reviewed our experience with 5-FC monotherapy for 27 patients treated between 1968 and 1973. Patients were selected on the basis of criteria associated with good prognosis. In this group, 5-FC monotherapy resulted in cure in eight cases and improvement in two. Overall, response was seen in 10 (43%) of 23 evaluable patients. Therapy failed for 13 patients, including 5 who relapsed, 2 who had partial responses, and 6 without response. Resistance was noted to have developed in isolates from six (50%) of 12 patients for whom therapy failed. Although the 57% failure rate associated with 5-FC alone precludes its use as monotherapy, our study did show that this treatment was well tolerated and that failure was not invariably associated with development of resistance.

Publication types

  • Clinical Trial

MeSH terms

  • Adult
  • Aged
  • Antifungal Agents / therapeutic use*
  • Cryptococcosis / drug therapy*
  • Cryptococcus neoformans / drug effects
  • Drug Resistance, Microbial
  • Female
  • Flucytosine / therapeutic use*
  • Humans
  • Male
  • Middle Aged
  • Treatment Outcome


  • Antifungal Agents
  • Flucytosine