Classic Whipple disease presenting as genuine pyrexia of unknown origin following immunosuppression with adalimumab

Whipple disease (WD) is a rare chronic multisystem infectious disorder caused by the bacterium <i>Tropheryma whipplei (T. whipplei)</i> and is more prevalent than previously thought. Its diagnosis is often delayed by months to years owing to its rarity, non-specific manifestations and insidious course. WD classically presents with polyarthropathy followed months to years later by the development of gastrointestinal symptoms, which often lead to the diagnosis. Pyrexia of unknown origin (PUO) without gastrointestinal involvement is an extremely rare presentation. We describe a case of WD presenting as genuine PUO following immunosuppression with the tumour necrosis factor-alpha monoclonal antibody adalimumab for seronegative polyarthropathy.