Monoclonal deposition diseases

Question 1

What is the full differential of renal diseases caused by monoclonal immunoglobulin molecules

Answer 1

Proximal tubulopathies – including acute tubular injury/necrosis with and without crystalline inclusions, acute tubulointerstitial nephritis and lysosomal indigestion/constipation variants

Light chain cast nephropathy/myeloma cast nephropathy

Crystalline glomerulopathy

Light and/or heavy chain deposition diseases

Light and/or heavy chain-associated amyloidosis (AL/AH amyloidosis)

Proliferative glomerulonephritis with monoclonal IgG deposits

Glomerulonephritis with isolated C3 deposits and monoclonal gammopathy

Question 2

What are the ‘proximal tubulopathies’?

Answer 2

Proximal tubulopathies – including acute tubular injury/necrosis with and without crystalline inclusions, acute tubulointerstitial nephritis and lysosomal indigestion/constipation variants

Question 3

How does MGRS usually present?

Answer 3

Most often proteinuria
*sometimes a mix of increased creatinine and proteinuria (proximal tubulopathies)

Question 4

What’s a good screening lab test for MGRS or myeloma?

Answer 4

serum free light chains
*also important workup is SPEP/UPEP with IFE