Mu heavy chain disease involves a chronic lymphocytic leukemia (CLL) with clonal production of an abnormal IgM heavy chain that is unable to bind light chains.


Clinical features:

(1) a rare disease affecting older adults

(2) hepatosplenomegaly without lymphadenopathy

(3) slowly progressive course


Laboratory features:

(1) CLL in the peripheral blood.

(2) Increase in truncated IgM heavy chains without light chains in the serum. The heavy chains may form polymers. The serum protein electrophoresis may be normal.

(3) Bence Jones free light chains may be present in the urine.

(4) The bone marrow shows a lymphoplasmacytic infiltrate with plasma cells showing cytoplasmic vacuoles.


To read more or access our algorithms and calculators, please log in or register.