In vitro susceptibility of C. neoformans isolates against FLU from HIV-negative CM patients in Guangdong, China.

OBJECTIVE

To investigate the epidemiology and in vitro susceptibility of Cryptococcus neoformans to fluconazole (FLU) in HIV-negative cryptococcal meningitis (CM) patients.

METHODS

Demographic and laboratory data, minimum inhibiting concentrations (MICs) of FLU, and 1-year outcomes from 270 CM patients in Guangdong Province, China, between 2011 and 2022 were retrospectively collected.

RESULTS

270 Cryptococcus neoformans isolates were analyzed, of which 49 (18.1%) were FLU-resistant isolates (MIC ≥8 μg/ml). The FLU MIC values and the proportion of FLU-resistant isolates showed no statistically significant temporal trend over the 12-year. However, the FLU MIC values (3.55 vs 2.84, p = 0.013) and the proportion of FLU-resistant isolates (23.9% vs 12.1%, p = 0.012) during the dry season (October to March) were higher than those during the rainy season (April to September). The 1-year mortality rates were 27.0% in the MIC ≥8 μg/ml group and 14.3% in the MIC < 8 μg/ml group. Kaplan-Meier curve showed a slight but non-significant divergence between the two groups (log-rank test p = 0.074).

CONCLUSIONS

No significant temporal trend in FLU MIC was observed. Although the majority of Cryptococcus neoformans isolates are susceptible to FLU, surveillance for emerging resistance may be warranted on a national basis.