Due to current therapy innovation the outcome for patients with light chain amyloidosis is improving.  However delay in diagnosis remains major problem to improving survival for this unfortunate group of patients.

  Hematologist and oncologist regularly monitor patients with monoclonal gammopathy of undetermined significance and smoldering multiple myeloma for the development of either crab criteria or a myeloma defining event.  Unfortunately a significant subset of patients with smoldering myeloma and MGUS have underlying amyloidosis in this diagnosis is frequently over looked.  in patients with amyloidosis the problems are fatigue dyspnea edema weight loss and paresthesias.  None of these fulfill the criteria of crab and these patients can go on monitoring as they decline due to progressive heart and renal failure.  Patients with neuropathy often undergo infusions of immunoglobulin and plasma exchange based on incorrect diagnosis of MGUS neuropathy.  These patients will have amyloid neuropathy in the diagnosis needs to be excluded in patients who have carpal tunnel syndrome or autonomic failure.

Patients with cardiac amyloid often developed progressive dyspnea on exertion in the absence of anemia or renal insufficiency and dyspnea may not be given sufficient weight to justify and evaluation.  Even referral to a cardiologist may result in a missed diagnosis of hypertensive her hypertrophic cardiomyopathy rather than infiltrative cardiomyopathy causing heart failure with preserved ejection fraction.  All patients with MGUS and smoldering myeloma need to be considered for the possibility of amyloidosis if there atypical features that do not fit crab criteria.  Moreover patients with amyloidosis do not have rising levels of monoclonal protein her light chain over time.  These patients are reassured the tear stable when in fact they are depositing amyloid in organs that is on recognized.  All  MGUS and smoldering myeloma patients that have atypical features such as progressive fatigue and edema or unexplained weight loss need screening for amyloidosis with measurements for urinary protein and cardiac biomarkers.  Specific points are given in our manuscript. 

Immunoglobulin light chain amyloidosis diagnosis and treatment algorithm 2021