MGUS (interpreting the test you didnt order) Family Medicine Review Course 2011 Christian Cable, MD, FACP
The Case
What is the laboratory abnormality? 10-3 = 7 Whats in there?
What comprises the blood?
Whats in blood... Cellular (bone marrow) – RBCs – Platelets – WBCs Plasma (liver) – Water – Proteins Albumin Antibodies Clotting factors
Proteins in the Blood?
Brainstorm As many globins as you can think of...
Tell me more about antibodies
What is the correct test?
SPEP/SIEP SPEP qualitative (is it there?) SIEP quantitative (how much, which one?)
Copyright ©2001 American Society of Hematology. Copyright restrictions may apply. Lazarchick, J. ASH Image Bank 2001;2001: Figure 8. Immunofixation electrophoresis showing a monoclonal IgA lambda light chain restricted band
Gammopa-what?
Greek to me (I)... Gamma - - region in electrophoretic mobility Pathy - - disease or condition
Greek to me (II)... Clonal - - type Mono - - one Poly - - many (much)
Differentiate Polyclonal from Monoclonal
M-spike
What is normal?
How high?
Polyclonal gammopathy - -significance Think of an elevated ESR What could cause that?
Is polyclonal gammopathy a plasma cell disorder?
Monoclonal gammopathy - - determined significance
New Myeloma Classification
Copyright ©2002 American Society of Hematology. Copyright restrictions may apply. Schrier, S. ASH Image Bank 2002;2002: Figure 2. This is a bone marrow aspirate from a patient with multiple myeloma showing the abnormal accumulation of malignant plasma cells
Copyright ©2001 American Society of Hematology. Copyright restrictions may apply. Lazarchick, J. ASH Image Bank 2001;2001: Figure 11. Skull x-ray showing multiple lytic areas
Monoclonal gammopathy - - undetermined significance
Common?
3% of population over 50 twice that prevalence African Americans
Defined M-spike < 3 g/dL absence of CRAB symptoms (at least those attributable to MM) - - tricky with pre-existing renal disease! Bone Marrow involvement <10% with clonal plasma cells
How to evaluate CBC, Creatinine, Calcium, SPEP/SIEP Skeletal survey (plain films)
When to refer
Higher risk non-Ig G (IgA & Ig M) African American total M spike: >1.5 g/dL
Why follow? Over 20 years: 1% per year turn into either Multiple Myeloma or another blood cancer Double that risk for non-IgG subtypes and African American patients
How do you follow it? Id like to help follow higher risk patients. Lower risk: – re-test in 6 months then annually
Our Patient
SPEP
SIEP 1.6 g/dL IgA kappa
Recommendations referral bone marrow biopsy