Guillain-Barré syndrome involving reproductive system revealed on ¹⁸F-FDG PET/CT: a case report

Guillain-Barré syndrome (GBS) is an immune-mediated acute inflammatory peripheral neuropathy. While it is well-established that its typical manifestations involve the peripheral nerves, it is noteworthy that involvement of the central nervous system and the reproductive system is exceedingly rare. Here we report the case of a 67-year-old man with GBS in whom the ¹⁸F-FDG PET/CT demonstrated systemic inflammatory hypermetabolism. The imaging revealed multifocal, heterogeneous high-activity along the nerve roots, cerebral cortex, hypothalamus, and medulla oblongata. Crucially, it also identified significant involvement of the right testis and the transition zone of the right prostate, suggesting direct inflammatory engagement of the reproductive system. This case underscores the potential of ¹⁸F-FDG PET/CT as a comprehensive imaging tool for assessing the extent of systemic disease and inflammatory activity in complex GBS presentations.