IL-5 in the plasma-cell-dominant Castleman disease: a nosological entity.

A 40-year-old male presented with a history of low-grade fever, weight loss, night sweats and breathlessness of 3 months duration. On examination, the patient had freely mobile lump in left lumbar region. The lump was surgically excised. Histological examination and immunohistochemistry of the specimen were consistent with the diagnosis of plasma cell variant of the Castleman disease. The patient had polyclonal hypergammaglobulinemia, anemia, eosinophilia and elevated interleukin (IL)-6 level. The level of IL-5 was not measured; however, the presence of eosinophilia indirectly suggests an increased IL-5 level. He obtained complete remission after resection of lump and 20 months of surgery had no signs and symptoms of diseases recurrence with normal hematological parameters. We discuss the role of IL-5 in the pathophysiology of the Castleman disease along with dysregulated overproduction of IL-6.