Table 2.

Electrophoresis, free light chains, and bone marrow studies

Patient	SPEP	SIFE	Free Light Chains (κ, λ, κ/λ ratio)	Bone Marrow
1	Hypogamma-globulinemia	Small monoclonal λ	2.29, 36.6, 0.06	10% plasma cells, λ light chain-restricted
2	Small abnormality in beta region	Small monoclonal IgA κ	3.99, 1.55, 2.57	25% plasma cells, κ light chain restricted
3	Negative	Negative	1.41, 1.39, 1.01	30–40% plasma cells, λ light chain restricted
4	M spike in gamma region	Monoclonal IgG κ	1.72, 0.37, 4.64	<5% plasma cells, κ light chain restricted

Normal values for free light chains: κ, 0.33 to 1.94 mg/dl, λ, 0.57 to 2.63 mg/dl; κ/λ ratio, 0.26 to 1.65. SPEP, serum protein electrophoresis.