Reflex sympathetic dystrophy syndrome in renal transplanted patients under immunosuppression with tacrolimus

Complex Regional Pain Syndrome Type I Following Non-Orthopedic Surgery: Case Report and Narrative Review

Complex regional pain syndrome type I (CRPS I)-or algodystrophy-is a rare disease that usually occurs after a traumatic event. It is characterized by typical clinical findings such as severe and disabling pain disproportionate to the injury, functional limitations, as well as sensory and vasomotor alterations. However, some people do not report any injury associated with algodystrophy onset in personal history. We describe the management of an unusual case of CRPS I which occurred during the long-term follow-up of percutaneous transluminal coronary angioplasty (PTCA) and performed a narrative review of algodystrophy in non-orthopedic surgery. A clinical case of a 44-year-old man with a spontaneous onset of CRPS I of the right ankle is presented. He did not refer to history of any memorable significant trigger event. Approximately 5 months before the onset of clinical manifestations, he received a PTCA via the right femoral approach. We suppose an association between CRPS and this procedure and propose a possible pathophysiologic mechanism. The patient was treated with intramuscular neridronate, which resulted in significant pain relief and improved his quality of life. A comprehensive clinical and instrumental evaluation in patients with CRPS is challenging but mandatory for a correct diagnosis. An extensive analysis of patient history is important for identifying any potential trigger event, including non-orthopedic procedures. Bone scan could have a pivotal role for improving diagnostic sensitivity and specificity in CRPS I. Neridronate was a safe and effective therapeutic approach for this patient, confirming the results of the high-quality evidence available.

Tacrolimus-Induced Pain Syndrome After Bone Marrow Transplantation: A Case Report and Literature Review

BACKGROUND

Calcineurin-inhibitor-induced pain syndrome (CIPS), a rare complication seen in patients with bone marrow transplants, is associated with the use of cyclosporine A (CsA) or tacrolimus (FK506). This case demonstrates the successful pain control of FK506-related CIPS in a 23-year-old male patient with previously reported characteristic clinical features of CIPS in addition to neuropathic symptoms and uncharacteristic imaging findings. On day 15 after the transplantation, the patient complained of severe pain in the lower limbs. Afterwards, the patient started to complain of pain on his hands and back too. During this period, FK506 levels ranged from 9.5 to 16.1 ng/mL. All laboratory exams were normal, except for an increased level of alkaline phosphatase (141 U/L). The pain was not ameliorated by various analgesic drugs. Although MRI done for our patient showed no typical radiological signs such as bone marrow edema, CIPS was suggested based on characteristic clinical features of CIPS. Of note, our patient's pain had neuropathic pain-like characteristics, unlike the pain in previously reported patients with CIPS.

CONCLUSION

The patient was treated successfully by switching FK506 to CsA and administrating gabapentin and nifedipine. Heightened awareness of this complication after bone marrow transplants may be needed for hematologists, otherwise CIPS can result in catastrophic consequences.

An Unusual Manifestation of Calcineurin Inhibitor-Induced Pain Syndrome in Kidney Transplantation: A Case Report and Literature Review

Patient: Female, 23

Final Diagnosis: Calcineurin inhibitor-induced pain syndrome

Symptoms: Back pain

Medication: —

Clinical Procedure: Supportive treatment

Specialty: Transplantology

Calcineurin inhibitor induces pain hypersensitivity by potentiating pre- and postsynaptic NMDA receptor activity in spinal cords

Calcineurin inhibitors, such as cyclosporin A and tacrolimus (FK506), have played a pivotal role in the preservation of allograft function. However, these drugs can cause unexplained severe pain in patients, often referred to as calcineurin inhibitor-induced pain syndrome (CIPS). Although calcineurin can regulate NMDA receptor (NMDAR) activity, the causal relationship between spinal synaptic plasticity and CIPS remains unknown. In this study, we showed that systemic administration of FK506 (1.5 mg kg(-1) day(-1)) for 7 days in rats led to long-lasting nociceptive and mechanical hypersensitivity. Whole-cell patch-clamp recordings in spinal cord slices revealed that FK506 treatment caused a large increase in the amplitude of NMDAR-mediated excitatory postsynaptic currents (EPSCs) of dorsal horn neurons evoked by dorsal root stimulation. The amplitude of NMDAR currents elicited by puff NMDA application to dorsal horn neurons was also significantly greater in FK506-treated than in vehicle-treated rats. The frequency of spontaneous and miniature EPSCs in most dorsal horn neurons was profoundly increased in FK506-treated rats and was reduced by blocking NMDARs. Furthermore, blocking GluN2A or GluN2B subunits similarly reduced the amplitude of evoked EPSCs and the frequency of miniature EPSCs in dorsal horn neurons of FK506-treated rats. In addition, intrathecal injection of an NMDAR antagonist or systemic administration of memantine effectively reversed nociceptive and mechanical hypersensitivity in FK506-treated rats. Our findings indicate that calcineurin inhibition increases glutamate-mediated nociceptive input by potentiating presynaptic and postsynaptic NMDAR activity in spinal cords. NMDAR antagonists may represent a new therapeutic option for the treatment of CIPS.

Sympathetic dystrophy associated with sirolimus therapy

The reflex sympathetic dystrophy syndrome (RSDS) in organ transplant recipients has only previously been reported in patients treated with calcineurin inhibitors. We retrospectively analyzed 393 renal transplant patients treated with sirolimus, 9 of whom developed RSDS. All the patients reported varying degrees of pain in the legs, affecting the knees, ankles, and/or feet, plus cutaneous erythema. The onset of pain ranged from 1-6 months after transplantation. At the time of diagnosis of RSDS, the mean serum creatinine was 1.4 mg/dL (range 1.0-1.7) and bone scintigraphy with 99mTc pyrophosphate showed increased uptake in all cases. The symptoms remitted 3-10 months after treatment (mean, 4 months) with calcitriol, with or without nifedipine or calcitonin, and in one case with suppression of sirolimus. We conclude that sirolimus therapy may induce RSDS in renal transplant recipients.

Leg bone pain syndrome in a patient with ulcerative colitis treated with cyclosporin

BACKGROUND

Leg bone pain syndrome is an unusual condition associated with the use of calcineurin antagonists, initially described in patients receiving allograft transplantation.

AIM

To describe the first known reported case of leg bone pain syndrome in a patient with ulcerative colitis receiving cyclosporin.

RESULTS

Investigations revealed no diagnostic features. Calcium channel blocker was used successfully in the treatment of this condition.

CONCLUSION

In the absence of diagnostic investigations, a high index of clinical suspicion is needed to diagnose and successfully manage leg bone pain syndrome. This may prevent further complications such as osteonecrosis that may arise.