Calcineurin-inhibitor-induced pain syndrome after bone marrow transplantation.

Calcineurin-inhibitor-induced pain syndrome (CIPS), a rare complication seen in patients with organ transplants, is associated with the use of calcineurin inhibitors (CIs) such as cyclosporine (CSP) and tacrolimus (FK). Patients with this syndrome usually present with severe leg pain. This case report demonstrates the successful pain control of this pain syndrome in a 42-year-old female patient who had been given CIs (FK and CSP) as an immunosuppressive agent after a bone marrow transplant. Twenty-one days after the transplantation, she complained of severe pain in her bilateral lower extremities; this lasted several weeks, and was resistant to ordinary analgesics such as intramuscular pentazocine, intravenous morphine, and even oral nifedipine, which is generally accepted as an effective analgesic agent for the pain in this syndrome. Due to the presence of allodynia, our patient's pain had neuropathic pain-like characteristics, unlike the pain in previously reported patients with other organ transplants. Her pain was successfully relieved by the administration of oral amytriptyline, clonazepam, oxycodone, and intravenous lidocaine, all of which ordinarily have an analgesic effect on neuropathic pain. CIPS in patients with hematopoietic stem cell transplants treated with FK may have a mechanism by which neuropathic pain may develop that is different from that in patients with other organ transplants.