SORA

Advancing, promoting and sharing knowledge of health through excellence in teaching, clinical practice and research into the prevention and treatment of illness

Dynamic ploidy changes drive fluconazole resistance in human cryptococcal meningitis.

Stone, NR; Rhodes, J; Fisher, MC; Mfinanga, S; Kivuyo, S; Rugemalila, J; Segal, ES; Needleman, L; Molloy, SF; Kwon-Chung, J; et al. Stone, NR; Rhodes, J; Fisher, MC; Mfinanga, S; Kivuyo, S; Rugemalila, J; Segal, ES; Needleman, L; Molloy, SF; Kwon-Chung, J; Harrison, TS; Hope, W; Berman, J; Bicanic, T (2019) Dynamic ploidy changes drive fluconazole resistance in human cryptococcal meningitis. J Clin Invest, 129 (3). pp. 999-1014. ISSN 1558-8238 https://doi.org/10.1172/JCI124516
SGUL Authors: Bicanic, Tihana Molloy, Sile

[img]
Preview
PDF Published Version
Available under License Creative Commons Attribution.

Download (5MB) | Preview

Abstract

BACKGROUND: Cryptococcal meningitis (CM) causes an estimated 180,000 deaths annually, predominantly in sub-Saharan Africa, where most patients receive fluconazole (FLC) monotherapy. While relapse after FLC monotherapy with resistant strains is frequently observed, the mechanisms and impact of emergence of FLC resistance in human CM are poorly understood. Heteroresistance (HetR) - a resistant subpopulation within a susceptible strain - is a recently described phenomenon in Cryptococcus neoformans (Cn) and Cryptococcus gattii (Cg), the significance of which has not previously been studied in humans. METHODS: A cohort of 20 patients with HIV-associated CM in Tanzania was prospectively observed during therapy with either FLC monotherapy or in combination with flucytosine (5FC). Total and resistant subpopulations of Cryptococcus spp. were quantified directly from patient cerebrospinal fluid (CSF). Stored isolates underwent whole genome sequencing and phenotypic characterization. RESULTS: Heteroresistance was detectable in Cryptococcus spp. in the CSF of all patients at baseline (i.e., prior to initiation of therapy). During FLC monotherapy, the proportion of resistant colonies in the CSF increased during the first 2 weeks of treatment. In contrast, no resistant subpopulation was detectable in CSF by day 14 in those receiving a combination of FLC and 5FC. Genomic analysis revealed high rates of aneuploidy in heteroresistant colonies as well as in relapse isolates, with chromosome 1 (Chr1) disomy predominating. This is apparently due to the presence on Chr1 of ERG11, which is the FLC drug target, and AFR1, which encodes a drug efflux pump. In vitro efflux levels positively correlated with the level of heteroresistance. CONCLUSION: Our findings demonstrate for what we believe is the first time the presence and emergence of aneuploidy-driven FLC heteroresistance in human CM, association of efflux levels with heteroresistance, and the successful suppression of heteroresistance with 5FC/FLC combination therapy. FUNDING: This work was supported by the Wellcome Trust Strategic Award for Medical Mycology and Fungal Immunology 097377/Z/11/Z and the Daniel Turnberg Travel Fellowship.

Item Type: Article
Additional Information: This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.
Keywords: AIDS/HIV, Drug therapy, Fungal infections, Infectious disease, 11 Medical And Health Sciences, Immunology
SGUL Research Institute / Research Centre: Academic Structure > Infection and Immunity Research Institute (INII)
Journal or Publication Title: J Clin Invest
ISSN: 1558-8238
Language: eng
Dates:
DateEvent
1 March 2019Published
28 January 2019Published Online
30 November 2018Accepted
Publisher License: Creative Commons: Attribution 4.0
Projects:
Project IDFunderFunder ID
097377/Z/11/ZWellcome Trusthttp://dx.doi.org/10.13039/100004440
MR/K000373/1Medical Research Councilhttp://dx.doi.org/10.13039/501100000265
340087European Research Councilhttp://dx.doi.org/10.13039/501100000781
PubMed ID: 30688656
Go to PubMed abstract
URI: http://openaccess.sgul.ac.uk/id/eprint/110591
Publisher's version: https://doi.org/10.1172/JCI124516

Actions (login required)

Edit Item Edit Item