Grebe SO et al. - The laboratory investigation showed persistently elevated levels of CRP, ESR, serum ferritin, and iPTH, whereas all other parameters were inconspicuous. The hisology displayed typical signs of nephrogenic systemic fibrosis. NSF can occur at any time after Gd exposure in the long term. Gd is a necessary, but not the sole cause of NSF. Certain other cofactors such as chronic inflammation and accelerated atherosclerosis seem to be involved.