Initially, he responded well to diuretics, angiotensin-converting enzyme (ACE) inhibition with improvement of the nephrotic state, preserved renal function and proteinuria of around 1 gr/d. During follow-up over six months, he developed worsening oedema, worsening renal function, proteinuria, hypoalbuminemia, rapidly increasing kappa light chains and SFLC ratio, and evidence of kappa light chain paraprotein on SPEP and immunofixation, fulfilling SLiM myeloma criteria based on the International Myeloma Working Group diagnostic criteria. Here, ACE is linked to plasma cell myeloma.