CCL2 and glycogen storage disease VI: In 2019, Messchendorp et al. [23] identified a urinary-biomarker score by summing the ranking of the tertiles of β2 microglobulin (β2M) and monocyte chemotactic protein-1 (MCP-1) excretion, with a high predictive value for rapidly progressive disease; this value was even higher than that of the Mayo htTKV classification or PKD mutation.