Abnormal circulating beta-CTX concentration Decreased circulating beta-CTX concentration 2017-09-16T11:22:56Z Decreased circulating beta-CrossLaps level The concentration of beta-CTX (= beta-C-terminal telopeptide, = beta-C-terminal telopeptide of type I collagen) in the blood circulation is below the lower limit of normal. Decreased circulating beta-CTx level Decreased circulating beta-C-terminal telopeptide level