Baseline fluconazole heteroresistance and risk of relapse within 6 months among patients with neurocryptococcosis in the Brazilian Amazon.

Heteroresistance to fluconazole, defined by HFL/MIC ≥8, was present in 61.4% of Cryptococcus isolates but was not significantly linked to six-month relapse in patients with neurocryptococcosis.

• Why it matters: Understanding factors that predict relapse in cryptococcosis is crucial for improving treatment outcomes, yet the role of heteroresistance remains unclear. Identifying whether heteroresistance influences relapse could guide therapy adjustments and prognosis.
• What they did: The study analyzed 70 cerebrospinal-fluid isolates from patients in Amazonas, Brazil, using broth microdilution and HFL testing to classify heteroresistance based on HFL/MIC ratios, and tracked relapse within six months.
• The result: Although relapse was more common in patients with heteroresistant isolates (28.6%) than in those without (14.8%), this difference was not statistically significant (p=0.248), indicating heteroresistance may not predict relapse in this cohort.