3rd Conf Retro and Opportun Infect. 1996 Jan 28-Feb 1;:157. Unique
Fluconazole has been used for treatment of histoplasmosis in patients
with AIDS but appears to be less effective than amphotericin B or
itraconazole. Treatment failure or relapse occurred in nearly half of
patients during a prospective trial (ACTG 174). The patient reviewed
here improved initially but remained fungemic and subsequently relapsed.
Isolates at week 8, 12 and 16 of therapy showed progressive increase in
fluconazole MIC from 0.625 micrograms/ml initially to 20 micrograms/ml
at relapse. Inhibition of ergosterol synthesis and accumulation of the
sterol intermediaries obtusifolione and eburicol during incubation with
fluconazole were reduced in the relapse isolate. The relapse isolate
remained fully susceptible to itraconazole. These findings indicate that
H. capssulatum may develop resistance to fluconazole and suggest that
its 14 alpha-demethylase and/or ketosteroid reductase changed
fluconazole treatment. Patients receiving fluconazole for histoplasmosis
are at risk for failure because of development of resistance.
Acquired Immunodeficiency Syndrome/*COMPLICATIONS Antifungal
Agents/*PHARMACOLOGY/THERAPEUTIC USE
Fluconazole/*PHARMACOLOGY/THERAPEUTIC USE Histoplasma/*DRUG
EFFECTS/ENZYMOLOGY Histoplasmosis/COMPLICATIONS/*DRUG THERAPY Human
Microbial Sensitivity Tests Treatment Failure ABSTRACT