Does removal of the light chains with plasmapharesis reduce the severity of cast nephropathy? We know that renal failure is a terrible prognostic factor in multiple myeloma so fixing acute renal failure is important.
Renal failure comes in many different flavors with myeloma:
- Light chain deposition disease
- Heavy chain deposition disease that I have never seen but Steve Rankin had a case as a fellow.
- Amylloidosis
- Hypercalcemia
- Cast nephropathy
Only the last is amenable to plasmapheresis. Whether it works has been the subject of three prospective randomized studies:
UPDATE
Though not randomized this recent article from KI should be of interest (Thanks Kyste):
Leung et al. Improvement of cast nephropathy with plasma exchange depends on the diagnosis and on reduction of serum free light chains. Kidney Int (2008) vol. 73 (11) pp. 1282-8.