Gamma heavy-chain disease presenting with hypercalcaemia and ascites

Gamma heavy-chain disease (gHCD) is a rare lymphoproliferative disorder characterised by the production of truncated gamma heavy chains that are not associated with light chains. We present the case of a 79-year-old man with a known history of chronic lymphocytic leukaemia who presented with acute confusion, hypercalcaemia and ascites. Workup revealed monoclonal gamma heavy chains in serum without corresponding light chains. Treatment with a combination of rituximab, bortezomib and prednisone resulted in complete remission, sustained over two years. This case highlights the diagnostic and therapeutic challenges of gHCD and underscores the importance of individualised management. LEARNING POINTS: Consider gamma heavy-chain disease in patients with unexplained monoclonal gammopathy and atypical presentations, such as hypercalcaemia and ascites.A combination of rituximab and chemotherapy shows an anti-tumour effect in gamma heavy-chain disease expressing CD20.