title: A cytologic diagnosis of BRAFV600EErdheim-Chester disease on pericardial fluid.
abstract: We report the case of a 74-year-old woman admitted to the emergency unit for resting dyspnea. Clinical presentation, cardiac MRI and echocardiography were consistent with cardiac tamponade requiring emergency pericardiocentesis. Cytologic examination of the pericardial fluid revealed the presence of CD68posCD1anegS100negfoamy histiocytes (Fig. 1). Additional investigations complied with the diagnosis of Erdheim-Chester histiocytosis. Treatment with αIFN was initiated but the patient developed severe neutropenia that contraindicated further administration. The detection of BRAFV600Emutation on histiocytes isolated from the pericardial liquid and CNS involvement (cerebral masses) prompted the administration of vemurafenib, a selective BRAFV600Ekinase inhibitor. Four months after the initiation of low-dose vemurafenib, pericarditis almost resolved and cerebral masses decreased by 50% (Fig. 2). To our knowledge, analysis of pericardial fluid allowing the diagnosis of Erdheim-Chester disease and the detection of the BRAFV600Emutation has in fact been rarely described in the literature. This case report and the successful evolution under vemurafenib also support the use of BRAFV600Einhibitors in αIFN-intolerant patients with BRAFV600Emutation, particularly in case of heart and central nervous system involvement.
authors.affiliation: a Internal Medicine Unit , Erasme Hospital, Université Libre de Bruxelles , Anderlecht , Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Chasseur
authors.affiliation: b Cardiology Unit , Erasme Hospital, Université Libre de Bruxelles , Anderlecht , Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Kyriakopoulou
authors.affiliation: a Internal Medicine Unit , Erasme Hospital, Université Libre de Bruxelles , Anderlecht , Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Vokaer
authors.affiliation: c Immunobiology, Hematology and Transfusion Unit , Erasme Hospital, Université Libre de Bruxelles , Anderlecht , Belgium.
authors.forename: I
authors.initials: I
authors.lastname: Beukinga
authors.affiliation: b Cardiology Unit , Erasme Hospital, Université Libre de Bruxelles , Anderlecht , Belgium.
authors.forename: R
authors.identifier: http://orcid.org/0000-0002-3876-6074
authors.initials: R
authors.lastname: Casado Arroyo
authors.affiliation: a Internal Medicine Unit , Erasme Hospital, Université Libre de Bruxelles , Anderlecht , Belgium.
authors.forename: E
authors.initials: E
authors.lastname: Cogan
authors.affiliation: a Internal Medicine Unit , Erasme Hospital, Université Libre de Bruxelles , Anderlecht , Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Couturier
mesh_terms: D000368:Aged; D031249:Erdheim-Chester Disease / Q000175:diagnosis* / Q000188:drug therapy / Q000473:pathology; D005260:Female; D006801:Humans; D007211:Indoles / Q000494:pharmacology / Q000627:therapeutic use; D000069236:Pericardial Fluid / Q000166:cytology*; D048493:Proto-Oncogene Proteins B-raf / Q000037:antagonists & inhibitors; D013449:Sulfonamides / Q000494:pharmacology / Q000627:therapeutic use; D000077484:Vemurafenib
chemical_list: D007211:Indoles; D013449:Sulfonamides; D000077484:Vemurafenib; D048493:Proto-Oncogene Proteins B-raf
keywords: BRAFV600E; Erdheim-Chester; Histiocytes; Pericardial fluid; Vemurafenib