Calcineurin-inhibitor induced pain syndrome - Magnetic resonance imaging and scintigraphic findings illustrated through two cases.

Calcineurin-inhibitor induced pain syndrome (CIPS) is a condition characterized by lower extremity pain in patients receiving tacrolimus or cyclosporine therapy following organ transplantation. Through two cases, we demonstrate key imaging findings in CIPS with bone scintigraphy and magnetic resonance imaging (MRI), which are those of increased scintigraphic activity and marrow edema in the lower extremities, respectively. CIPS is an important condition that has characteristic imaging findings, but is unfortunately underappreciated in the radiology literature. To our knowledge, this is the first article in the radiology literature presenting two cases of CIPS, as well as the first to present both scintigraphic and MRI findings in this condition.