SOST and rheumatic disorder: On one hand, Dkk-1 has been found to be dysregulated (excessively expressed) in rheumatic disease characterised by systemic inflammation with local/systemic bone loss [40,41] and to decrease after successful anti-inflammatory treatment [42,43,44], with sclerostin being excessively elevated in patients deficient in vitamin D with chronic kidney disease and associated with poor fracture outcomes [45].