Cryptococcus gattii: immunological and microbiological study in a patient with neurocryptococcosis

Dewton De Moraes Vasconcelos,Marcos Ereno Auler,Maria Cecília Pereira Soares,Maurício Domingues-Ferreira,Claudete Rodrigues Paula,Marilena Dos Anjos Martins,Thiago De Almeida Bezerra

doi:10.1099/jmmcr.0.000099

Abstract

Introduction: Cryptococcal meningitis is a disease that remains a significant cause of morbidity and mortality. This report describes the importance of conducting a detailed clinical investigation and the treatment challenges in cases of meningitis caused by Cryptococcus gattii. In recent years this species has received considerable interest due to its increased emergence and virulence. Case presentation: A patient with apparent good health (a fitness practitioner) showed symptoms including intermittent headache that became more intense and frequent when he began experiencing nausea, vomiting, dizziness and temporal headache without nuchal rigidity. The patient had human immunodeficiency virus-negative serology and had no chronic disease. Analysis of cerebrospinal fluid was performed and cryptococcal meningitis was diagnosed. Immunophenotyping by flow cytometry evidenced the presence of an anomalous lymphoid population. RFLP analysis of the URA5 gene indicated Cryptococcus gattii genotype VGII and considerable virulence was observed for the isolated strain. Conclusion: This case suggests the importance of a detailed investigation in patients who apparently have a competent immune system with meningitis caused by Cryptococcus spp., particularly C. gattii.

Highlights

Cryptococcal meningitis is a disease that remains a significant cause of morbidity and mortality
Cryptococcus neoformans is the most common human pathogenic species; non-neoformans Cryptococcus have been reported (Saijo et al, 2014). Another species that has been observed in cases of cryptococcal meningitis is Cryptococcus gattii, which can affect immunocompetent and non-immunocompromised hosts (Chen et al, 2014), and the infections may be more difficult to treat (Perfect et al, 2010)
On 9 February, the patient was admitted to a hospital, where a lumbar puncture was performed and cryptococcal meningitis was diagnosed in the cerebrospinal fluid

Summary

Introduction

Cryptococcosis is a serious medical problem, amongst immunocompromised patients, and remains the most important cause of fungal meningitis (Li et al, 2012). Cryptococcus neoformans is the most common human pathogenic species; non-neoformans Cryptococcus have been reported (Saijo et al, 2014) Another species that has been observed in cases of cryptococcal meningitis is Cryptococcus gattii, which can affect immunocompetent and non-immunocompromised hosts (Chen et al, 2014), and the infections may be more difficult to treat (Perfect et al, 2010). On 9 February (day +209), the patient was admitted to a hospital, where a lumbar puncture was performed and cryptococcal meningitis was diagnosed in the cerebrospinal fluid. The evaluation of T-cell subsets showed a population of double-negative T-cells expressing cd T-cell receptors, which, following more detailed phenotyping, showed aberrant cells expressing CD19+CD16+CD56+ CD123+ in 6 % of peripheral blood lymphocytes His exams demonstrated the presence of IgG l paraprotein. The present study was approved by the research ethics committee CAPPESQ-USP (no. 0478/2011) and the patient provided written informed consent

Findings

Discussion