1357771 - Rare cardiac manifestation of idiopathic Multicentric Castleman Disease and its differential diagnosis

A 54-year female was referred for Cardiac MR (CMR) due to focal hypermetabolism in the basal anterior wall of the left ventricle (LV) on PET-CT performed for suspected infiltrative disease following identification of splenomegaly with a heterogeneous focal lesion on ultrasound. The patient had been diagnosed with Antiphospholipid syndrome 3 years prior after lower limb deep vein thrombosis. Her past medical history includes chronic fatigue, anemia, elevated CRP, renal dysfunction, polyclonal hypergammaglobulinemia, and hypoalbuminemia. She had no history of infectious symptoms and was not immunocompromised.

Diagnostic Techniques and Their Most Important Findings:

CMR showed epicardial and subepicardial hyperintensity on b-SSFP cine images (Fig. 1 A and D) and epicardial and subepicardial late gadolinium enhancement (LGE) (Fig. 1 B and E) in the basal anterior segment of the LV with associated elevated native T1 mapping (Fig. 1 C and F). Both ventricles showed normal size and systolic function.

Abdominal MR displayed splenomegaly, heterogeneous splenic signal intensity and enhancement (Fig. 2 A to D), lymphadenopathy and bilateral T2 hypointense perirenal soft tissue (Fig. 2 E to H).

PET-CT showed multiple sites of hypermetabolism involving basal anterior LV wall (Fig. 3 A to C), spleen (Fig. 3D), perinephric soft tissue (Fig. 3E), lymph nodes (Fig. 3E), and bone marrow (Fig. 3F).

Bone marrow biopsy was normal. The differential considerations on lymph node biopsy were an infectious process, lymphadenopathy associated to autoimmune disease and plasma cell variant of Castleman disease. IgG4 related disease was excluded by the low IgG4/IgG ratio. There was no evidence or lymphoma or carcinoma. A final clinical diagnosis of idiopathic Multicentric Castleman Disease (iMCD) was made based on international consensus diagnostic criteria (1).

Learning Points from this Case:

Cardiac involvement although rare, can occur in iMCD. The few cases reported in the literature showed coronary pseudoaneurysm (2), cardiomyopathy, pericarditis and cardiac tamponade (3).

Cardiac involvement in our patient was seen as late gadolinium enhancing hyperintense area within the epicardial and subepicardial region of the basal anterior LV wall. Differential diagnosis of epicardial and subepicardial abnormality (4) includes common causes such as myocarditis, less common conditions such as sarcoidosis and lymphoma and rare diseases such as IgG4, Erdheim-Chester, Rosai-Dorfman and Castleman disease (CD).

MCD is a lymphoproliferative disorder characterized by systemic inflammation and organ dysfunction. CD can mimic many disorders (5) including malignancy, autoimmune and infectious diseases due to significant clinical, histologic, and immunologic overlap. The more common unicentric CD is a benign disorder which presents as localized mass.

Systemic disease with cardiac involvement is not uncommon, therefore, for a correct diagnosis we must consider the cardiac CMR findings in correlation with a good clinical approach, multimodality imaging and histopathology findings.