Table 1.

Suggested reference values for serum free light chains.^a

Population	No. of individuals	κ FLC, mg/L	λ FLC, mg/L	Total FLC, mg/L	Ratio
Healthy donors	282	7.3 (0.8–34.7)	12.4(2.7–37.4)	20.5 (3.5–72.1)	0.59 (0.26–1.65)
Renal impairment	688	43.8 (3–251)	38.0 (1.0–251)	82 (8.57–497)	1.12 (0.37–3.17)
Polyclonal hypergammaglobulinemia	25	19.6 (4.3–273)	28.8 (8.5–307)		0.55 (0.38–1.18)

^aFLC data and the κ/λ FLC ratio are presented as the median (range). From Katzmann et al. (9) and Hutchison et al. (10).