# Autoantibodies neutralizing GM-CSF in HIV-negative Colombian patients infected with Cryptococcus gattii and C. neoformans

## TL;DR

Some Colombian patients with cryptococcosis have autoantibodies that block GM-CSF, a finding more common in those infected with Cryptococcus gattii.

## Contribution

This study identifies a high prevalence of GM-CSF-neutralizing autoantibodies in HIV-negative Colombian patients with cryptococcosis, particularly those infected with C. gattii.

## Key findings

- Autoantibodies neutralizing GM-CSF were detected in 69% of patients infected with C. gattii.
- Only 6% of patients infected with C. neoformans had GM-CSF-neutralizing autoantibodies.
- Nine out of ten patients with these autoantibodies were infected with C. gattii.

## Abstract

Cryptococcosis is a life-threatening disease caused by Cryptococcus neoformans or C. gattii. Autoantibodies (auto-Abs) neutralizing granulocyte-macrophage colony-stimulating factor (GM-CSF) in otherwise healthy adults with cryptococcal meningitis have been described since 2013. We searched for neutralizing auto-Abs in sera from Colombian patients with non-HIV related cryptococcosis in a retrospective national cohort collected from 1997 to 2016.

We reviewed clinical and laboratory records and assessed the presence of neutralizing auto-Abs in 30 HIV (−) adults presenting cryptococcosis (13 by C. gattii, and 17 by C. neoformans).

We detected auto-Abs neutralizing GM-CSF in the plasma of 9 out of 13 (69%) patients infected with C. gattii and 1 out of 17 (6%) patients with C. neoformans.

We report ten Colombian patients with cryptococcosis due to auto-Abs neutralizing GM-CSF. Nine of the ten patients were infected with C. gattii, and only one with C. neoformans.