tacrolimus and Back-Pain

BACKGROUND Calcineurin inhibitors (CNI) are the mainstay immunosuppressive drugs for kidney transplantation. Although they provide excellent allograft and patient outcomes, adverse effects are frequently encountered. Calcineurin inhibitor-induced pain syndrome (CIPS) is a rare adverse effect of CNI. Previous case reports with CIPS diagnosis involved incapacitating pain in the lower extremities. CASE REPORT In this article, we report the first case of CIPS with severe back pain as the presenting symptom, which was correlated with a high tacrolimus trough concentration due to a drug interaction with clotrimazole troche. Magnetic resonance imaging (MRI) of the spine showed bone marrow edema, which is consistent with previous case reports. The patient's symptoms resolved within 3 weeks of the onset of pain. Treatments were symptomatic care and lowering the tacrolimus trough concentration. Pain was improved significantly with pregabalin but not with nifedipine. CONCLUSIONS We reviewed the literature of kidney transplant cohorts with CIPS to ascertain prevalence, pain characteristics, and treatment outcomes. Apart from our case, all patients experienced lower extremities pain and were pain-free during the follow-up period, without any residual abnormalities. CIPS is a benign but adverse effect of CNI. Counselling patients about the disease's natural history and supportive care remain the best treatment.

Topics: Anti-Infective Agents, Local; Back Pain; Calcineurin Inhibitors; Clotrimazole; Drug Interactions; Female; Humans; Kidney Transplantation; Tacrolimus; Young Adult

Osteoporosis is known to occur in patients with kidney transplants, but limited information is available about the prevalence and causes of this complication. We asked all 330 patients with kidney transplants in our unit to participate in this study of whom 165 (50%) agreed to do so. The characteristics of the participating patients were similar to the remaining 165 nonparticipants. Seventy of 165 (42%) of the participants were women of whom 40 were postmenopausal in contrast to the men of whom only one was hypogonadal. Bone mineral density (BMD) was significantly reduced at the radius (Z score, -1.5) and femoral neck (Z score, -0.7), but the lumbar spine was normal. BMD was lower in women than men at all skeletal sites. Osteoporosis was found in 10-44% and osteopenia was found in 35-50% of women depending on the site. BMD was related inversely to time since transplantation and cumulative prednisolone dose. Twenty-seven of the 165 (16%) patients had either vertebral deformities or a history of a low trauma fracture after transplantation. This fracture group consisted of 10/27 (37%) men and 17/27 (63%) women, of whom 14 were postmenopausal. Fracture patients tended to be older and have a longer duration of renal failure, dialysis, transplantation, greater cumulative steroid dose, and higher bone resorption markers than the nonfracture group. No differences were found for cumulative doses of cyclosporin or tacrolimus. Logistic regression showed that only duration of dialysis and time since transplantation significantly increased fracture risk, with odds ratio (OR) for each year of dialysis or transplantation being 1.21 (CI, 1.00-1.48) and 1.14 (CI, 1.05-1.23), respectively. These data show that low bone density and fractures are common in patients with kidney transplant and are determined by both pre- and posttransplant variables. Fracture risk was greatest in women, particularly if they were postmenopausal and we recommend that this subgroup is targeted for assessment and treatment.

Topics: Adolescent; Adult; Aged; Aged, 80 and over; Azathioprine; Back Pain; Biomarkers; Bone Density; Cyclosporine; Female; Fractures, Bone; Humans; Kidney Transplantation; Male; Middle Aged; Prednisolone; Prevalence; Tacrolimus; United Kingdom