Nephrogenic systemic fibrosis is a sclerodermalike disease in patients with acute or chronic renal insuffiency related to administration of gadolinium-containing contrast agents. Previous studies have demonstrated clonal T-cell populations in the blood of patients with systemic sclerosis, suggesting that these cells may be involved in the pathogenesis of the disease. Facing the clinical similarities of both diseases, we hypothesized that clonal expansion of T cells could be present in nephrogenic systemic fibrosis as well.
Findings from polymerase chain reaction and high-resolution capillary electrophoresis for T-cell receptor γ gene rearrangement analysis showed that all 6 prospectively evaluated patients (100%) with nephrogenic systemic fibrosis had detectable clonal T cells in their peripheral blood. In contrast, only 4 of the 15 control patients (27%) with chronic renal failure and none of the 12 healthy individuals analyzed in this study had evidence for T-cell clonality using the same type of examination. Clonal T-cell–positive patients with systemic sclerosis have previously been reported to better respond to extracorporeal photopheresis. However, this was not the case in 2 of our patients with nephrogenic systemic fibrosis.
As in systemic sclerosis, clonally expanded T-cell populations could play a critical role in the pathogenesis of nephrogenic systemic fibrosis, probably as an in vivo–activated inflammatory response to gadolinium exposure.