Transcript MGUS (interpreting the test you didn’t order)

MGUS
(interpreting the test you didn’t order)
Family Medicine Review Course 2011
Christian Cable, MD, FACP
The Case
What is the laboratory abnormality?
• 10-3 = 7
• What’s in there?
What comprises the blood?
What’s 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?)
Figure 8. Immunofixation electrophoresis showing a monoclonal IgA lambda light chain
restricted band
Lazarchick, J. ASH Image Bank 2001;2001:100185
Copyright ©2001 American Society of Hematology. Copyright restrictions may apply.
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
Figure 2. This is a bone marrow aspirate from a patient with multiple myeloma showing the
abnormal accumulation of malignant plasma cells
Schrier, S. ASH Image Bank 2002;2002:100514
Copyright ©2002 American Society of Hematology. Copyright restrictions may apply.
Figure 11. Skull x-ray showing multiple lytic areas
Lazarchick, J. ASH Image Bank 2001;2001:100185
Copyright ©2001 American Society of Hematology. Copyright restrictions may apply.
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?
• I’d 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
[email protected]