Impact of late calcineurin inhibitor withdrawal on ambulatory blood pressure and carotid intima media thickness in renal transplant recipients.

BACKGROUND: Calcineurin inhibitors (CNIs) have an unfavorable cardiovascular risk profile in renal transplant recipients. The aim of this substudy was to assess the effects of late CNI or mycophenolate mofetil (MMF) withdrawal on ambulatory blood pressure monitoring and carotid intima media thickness. METHODS: A total of 119 stable renal transplant recipients on triple regimen with steroids, a CNI and MMF were randomized into either the concentration-controlled CNI or MMF withdrawal groups. Patients were treated for traditional cardiovascular risk factors according to predefined targets. Ambulatory blood pressure monitoring and measurements of intima media thickness were performed at baseline and after 1, 2, and 3 years after randomization. RESULTS: CNI withdrawal resulted in a significant decline in both ambulatory day- and nighttime blood pressures (daytime: systolic blood pressure, -1.6 mm Hg/y, P=0.018; diastolic blood pressure, -1.3 mm Hg/y, P=0.002; nighttime systolic blood pressure: -1.9 mm Hg/y, P=0.008; diastolic blood pressure: -1.3 mm Hg/y, P=0.014), which was not observed after MMF withdrawal. There was no difference in the proportion of nocturnal nondippers (both groups, 69%, P=0.95). Despite the reduction in ambulatory blood pressure, no effect of CNI withdrawal on carotid intima media thickness was found. CONCLUSION: In stable renal transplant recipients, late CNI withdrawal from a triple drug regimen decreased blood pressure in comparison with MMF withdrawal but had no specific impact on carotid intima media thickness. Considering the high prevalence of hypertension in patients on CNI therapy, most stable renal transplant recipients may benefit from late CNI withdrawal by improved blood pressure control.

Late calcineurin inhibitor withdrawal prevents progressive left ventricular diastolic dysfunction in renal transplant recipients.

BACKGROUND: Calcineurin inhibitor (CNI)-based therapy is associated with adverse cardiovascular effects. We examined the effects of late CNI or mycophenolate mofetil (MMF) withdrawal on echocardiographic parameters. METHODS: This study was conducted as a substudy of a randomized trial in stable renal transplant recipients who were on a triple CNI-based regimen with prednisone and MMF that evaluated late concentration-controlled withdrawal of CNI or MMF on renal function. A total of 108 patients (age, 52.3±11.5 years; 67% male; at a median of 2.0 years post-transplantation, (interquartile range 1.3-3.3 years); estimated glomerular filtration rate, 57±16 mL/min/1.73 m; 66% on cyclosporine and 34% on tacrolimus) entered the cardiovascular substudy examining echocardiographic parameters at baseline and 2 years after randomization. In all patients, traditional cardiovascular risk factors were treated according to predefined targets. RESULTS: Late CNI withdrawal prevented progressive development of left ventricular (LV) diastolic dysfunction, as assessed by markers of LV diastolic function (mitral deceleration time and mitral annular e' velocity). Conversely, in the MMF-withdrawal group, the left atrial volume index (an indicator of chronic LV diastolic dysfunction) was significantly increased at 2 years (from 24.1±6.7 to 27.0±7.0 mL/m, P<0.05). In addition, CNI withdrawal resulted in a higher proportion of patients achieving the predefined blood pressure targets (<130/85 mm Hg: 41.5% vs. 12.7%, P=0.001) at 2 years while requiring less antihypertensive drugs. Changes in the left atrial volume index were significantly associated with treatment arm (P=0.03) and changes in systolic (P=0.005) and diastolic (P=0.005) blood pressure. CONCLUSIONS: Late CNI withdrawal, from a triple-drug regimen in stable renal transplant recipients, prevented progressive deterioration of LV diastolic function and facilitated better blood pressure control.

Randomized trial comparing late concentration-controlled calcineurin inhibitor or mycophenolate mofetil withdrawal.

BACKGROUND: Early calcineurin inhibitor (CNI) withdrawal with mycophenolate mofetil (MMF) has not become routine practice, due to concerns about excess acute rejection. Therapeutic drug monitoring may be advantageous when the CNI or MMF is withdrawn. METHODS: This prospective, randomized, concentration-controlled withdrawal study enrolled 177 stable renal transplant recipients on maintenance CNI-based immunosuppression, combined with steroids and MMF. After the feasibility phase of the study, patients were randomized to MMF-withdrawal (target area under the time-concentration curve-cyclosporine: 3250 ng·hr/mL or tacrolimus: 120 ng·hr/mL) or CNI-withdrawal (target area under the time-concentration curve-mycophenolic acid: 75 µg·hr/mL). RESULTS: The estimated glomerular filtration rate (modification of diet in renal disease) remained significantly better after CNI elimination (59.5±2.1 mL/min vs. 51.1±2.1 mL/min, P = 0.006) up to 3 years and resulted in less functional decline, including the subgroup with an estimated glomerular filtration rate less than 50 mL/min at baseline (P = 0.03). At 6 months, one patient in the MMF-withdrawal group (1.3%) and three in the CNI-withdrawal group (3.8%) experienced acute rejection (P = 0.62). The defined higher mycophenolic acid exposure was well tolerated. CONCLUSION: These data indicate that with time the large majority of stable renal transplant recipients can be safely reduced to dual therapy with MMF or CNIs, applying concentration-controlled dosing. CNI-free patients, including those with moderate renal allograft dysfunction, have the benefit of improved renal function, whereas the risk of acute rejection after late withdrawal is low.

Treatment failure in Haemophilus influenzae due to a beta-lactamase low-level ampicillin-resistant organism.

Haemophilus influenzae is a rare causative organism of vertebral osteomyelitis in an adult. Cases reported in the literature were mainly caused by ampicillin-susceptible type b strains. Here we describe the first case of vertebral osteomyelitis due to a non-typeable, beta-lactamase low-level ampicillin-resistant H. influenzae strain with failure of prolonged intravenous amoxicillin treatment.