We present a case of the multicentric plasma cell variant of Castleman's disease (CD) with two rare manifestations. The patient consulted us because of cutaneous vasculitis of the lower limbs, while constitutional symptoms were nearly absent. Imaging studies also revealed pulmonary parenchymal involvement. Furthermore, our patient is the first case in whom association of ankylosing spondylitis with CD is reported. In addition, we present a review of the literature with emphasis on the clinical presentation of CD and its difficult discrimination from autoimmune and infectious disorders. An overview of the therapeutic options is also provided.