Rare cause of pericardial effusion: 'Erdheim-Chester disease'.

This report details the case of a woman in her 50s who presented with symptoms of congestive heart failure and raised inflammatory biochemical markers. Her investigations included an echocardiogram, which revealed a large pericardial effusion and a subsequent CT-thorax/abdomen/pelvis showing extensive retroperitoneal, pericardial and periaortic inflammation and soft-tissue infiltration. Genetic analysis of histopathological samples detected a V600E or V600Ec missense variant within codon 600 of the BRAF genewith BRAF variants, confirming the diagnosis of Erdheim-Chester disease (ECD).The patient's clinical management involved several treatments and interventions with input from a variety of clinical specialties. This included the cardiology team for pericardiocentesis, the cardiac surgical team for pericardiectomy due to recurrent pericardial effusions and finally the haematology team for further specialist treatment with pegylated interferon and consideration of BRAF inhibitor therapy. The patient became stable following treatment with significant improvement in her heart failure symptoms. She remains under regular joint cardiology and haematology team follow-up. The case highlighted the importance of using a multidisciplinary approach to best manage the multisystem involvement of ECD.