Intravascular large B-cell lymphoma with preceding syndrome of inappropriate secretion of antidiuretic hormone.

Intravascular large B-cell lymphoma (IVL) is a rare subtype of B-cell lymphoma presenting with neurological and dermatological lesions in addition to generalized symptoms such as fever and malaise. It may also be associated with variable manifestations of affected organs due to extranodal progression predominantly in the lumen of the small vessels. Here, we report a case of IVL with the syndrome of inappropriate secretion of antidiuretic hormone (SIADH) as the sole manifestation at the initial presentation. The present case suggests that hormonal disturbances may progress in advance in IVL, before generalized symptoms develop.