title: Light chain deposition disease presenting as paroxysmal atrial fibrillation: a case report.
abstract: BACKGROUND
  Light chain deposition disease (LCDD) can involve the heart and cause severe heart failure. Cardiac involvement is usually described in the advanced stages of the disease. We report the case of a woman in whom restrictive cardiomyopathy due to LCDD presented with paroxysmal atrial fibrillation.
  
  
  METHODS
  A 55-year-old woman was admitted to our emergency department because of palpitations. In a recent blood test, serum creatinine was 1.4 mg/dl. She was found to have high blood pressure, left ventricular hypertrophy and paroxysmal atrial fibrillation. An ACE-inhibitor was prescribed but her renal function rapidly worsened and she was admitted to our nephrology unit. On admission serum creatinine was 9.4 mg/dl, potassium 6.8 mmol/l, haemoglobin 7.7 g/dl, N-terminal pro-brain natriuretic peptide 29894 pg/ml. A central venous catheter was inserted and haemodialysis was started. She underwent a renal biopsy which showed kappa LCDD. Bone marrow aspiration and bone biopsy demonstrated kappa light chain multiple myeloma. Echocardiographic findings were consistent with restrictive cardiomyopathy. Thalidomide and dexamethasone were prescribed, and a peritoneal catheter was inserted. Peritoneal dialysis has now been performed for 15 months without complications.
  
  
  CONCLUSIONS
  Despite the predominant tubular deposition of kappa light chain, in our patient the first clinical manifestation of LCDD was cardiac disease manifesting as atrial fibrillation and the correct diagnosis was delayed. The clinical management initially addressed the cardiovascular symptoms without paying sufficient attention to the pre-existing slight increase in our patient's serum creatinine. However cardiac involvement is a quite uncommon presentation of LCDD, and this unusual case suggests that the onset of acute arrhythmias associated with restrictive cardiomyopathy and impaired renal function might be related to LCDD.
authors.affiliation: Renal Unit, St, Anna Hospital, Ferrara, Italy. hrfabbia@tin.it.
authors.forename: Fabio
authors.initials: F
authors.lastname: Fabbian
authors.forename: Nevio
authors.initials: N
authors.lastname: Stabellini
authors.forename: Sergio
authors.initials: S
authors.lastname: Sartori
authors.forename: Paola
authors.initials: P
authors.lastname: Tombesi
authors.forename: Arrigo
authors.initials: A
authors.lastname: Aleotti
authors.forename: Maurizio
authors.initials: M
authors.lastname: Bergami
authors.forename: Simona
authors.initials: S
authors.lastname: Uggeri
authors.forename: Adriana
authors.initials: A
authors.lastname: Galdi
authors.forename: Christian
authors.initials: C
authors.lastname: Molino
authors.forename: Luigi
authors.initials: L
authors.lastname: Catizone