15th July 2024

Pathophysiology

There are myriad mechanisms by which renal damage may occur. The most common is cast nephropathy, where excess urinary free IgG light chains aggregate with Tamm-Horsfall proteins in the distal tubules leading to local atrophy and fibrosis.  In addition, hypercalcaemia secondary to increased bone resorption increases the incidence of nephrocalcinosis. Another mechanism includes immunoglobulin and free light chain deposition (and/or amyloid proteins) which may have direct toxic effects or contribute to glomerular damage.

It should be remembered that a number of additional factors may be present that could exacerbate renal failure in myeloma patients:

• volume depletion
• NSAIDs for pain control
• chemotherapy agents
• bisphosphonate use