Monitoring of blood cyclosporine concentration in steroid-resistant nephrotic syndrome

Cyclosporine A C1.5 monitoring reflects the area under the curve in children with nephrotic syndrome: a single-center experience

BACKGROUND

The currently used single-monitoring method for drug-blood-level evaluation in cyclosporine A (CsA) treatment for nephrotic syndrome (NS) was established through hourly measurements based on adult organ transplantation. However, the pharmacokinetics may differ due to different concomitant medications, age, and conditions. This study was conducted to determine the measurement timing that best reflects the CsA area under the curve (AUC) in pediatric NS.

METHODS

This retrospective study included children aged 2-14 years who were started on CsA treatment for idiopathic NS during 2013-2020. AUC_0-4 was calculated from 7 points, before and 0.5, 1, 1.5, 2, 3, and 4 h after administration. Mean values at each timing were compared with age-dependent different drug forms. Correlation between AUC_0-4 and measurement timing was analyzed.

RESULTS

There were 13 patients (11 boys) whose median age during testing was 7.3 years, and the total number of measurements was 94. The highest timing of CsA concentrations was found in C₁ 59.6%. The content liquid used at younger ages had a faster absorption time to peak value and lower blood concentration than those of capsules. Among the significant correlations observed, AUC_0-4 and C_1.5 showed the strongest significant correlation coefficient (r = 0.93, P < 0.001).

CONCLUSION

In pediatric NS, CsA metabolism may be faster than that in previous organ transplantation. Compared with C₂, C_1.5 monitoring may result in better disease control as it can best reflect the AUC_0-4 and peak values associated with side effects, which are indicators of therapeutic efficacy.

The First Case of Eosinophilic Granulomatosis with Polyangiitis Simultaneously Demonstrating Various Clinical Manifestations with Retroperitoneal Fibrosis and Membranous Nephropathy

The first case of eosinophilic granulomatosis with polyangiitis (EGPA) simultaneously demonstrating various clinical manifestations, including retroperitoneal fibrosis (RPF) causing hydronephrosis and membranous nephropathy (MN) leading to nephrotic syndrome, is presented. There have been no previous case reports demonstrating the simultaneous onset of these three disease categories with significant complex pathologies. This case was successfully managed by providing adequate combination therapies according to each disease category, leading to complete remission (CR) of all three diseases. In conclusion, we believe this case is extremely rare and clinically suggestive, and that these findings can be applied to a future phenotype-tailored treatment strategy for EGPA.

A Case of Frequently Relapsing Minimal-Change Nephrotic Syndrome with Steroid-Induced Psychiatric Syndrome Treated by Low-Dose, Short-Term Steroid Therapy in Combination with Cyclosporine

Adults with minimal-change nephrotic syndrome (MCNS) generally receive oral prednisolone (PSL) at an initial dosage of 1.0 mg/kg/day for a minimum of 4 weeks, with 80% of patients achieving clinical remission. However, relapses are frequent, necessitating repeated treatment with high-dose PSL. Long-term treatment with high-dose steroids increases the risk of steroid toxicities, such as diabetes mellitus, gastric complications, infections, osteoporosis, and steroid-induced psychiatric syndrome (SIPS), which may compromise the patient's quality of life. Strategies are therefore needed to reduce the dosage and duration of steroid therapy for frequently relapsing MCNS (FRNS). Here, we suggest a new combination therapy of low-dose and short-term steroid with cyclosporine (CsA). We encountered an adult patient who developed recurrence of FRNS with depression arising from SIPS and was treated using low-dose, short-term PSL combined with CsA. He was successfully treated with PSL at an initial dosage of 0.3 mg/kg/day (20 mg/day) for just 2 weeks combined with CsA, allowing earlier induction of complete remission. We then promptly reduced the dose of PSL to below a physiological dosage (5 mg/day) over 3 weeks without relapse after episodes of SIPS and quickly resolved psychiatric symptoms. CsA in combination with PSL can reduce the initial dosage of PSL, shorten the time to remission, and easily maintain clinical remission. This protocol appears clinically useful and potentially applicable as a future treatment strategy for FRNS troubled by SIPS.

Pharmacokinetics of cyclosporin--a microemulsion in children with idiopathic nephrotic syndrome

OBJECTIVE

We present a prospective study of a microemulsion of cyclosporin to treat idiopathic nephrotic syndrome in ten children with normal renal function who presented cyclosporin trough levels between 50 and 150 ng/ml and achieved complete remission with cyclosporin. To compare the pharmacokinetic parameters of cyclosporin in idiopathic nephrotic syndrome during remission and relapse of the nephrotic state.

METHOD

The pharmacokinetic profile of cyclosporin was evaluated with the 12-hour area under the time-concentration curve (auc0-12) using seven time-point samples. This procedure was performed on each patient during remission and relapse with the same cyclosporin dose in mg/kg/day. The 12-hour area under the time-concentration curve was calculated using the trapezoidal rule. All of the pharmacokinetic parameters and the resumed 4-hour area under the time-concentration curve were correlated with the 12-hour area under the time-concentration curve. ClinicalTrials.gov: NCT01616446.

RESULTS

There were no significant differences in any parameters of the pharmacokinetic of cyclosporin during remission and relapse, even when the data were normalized by dose. The best correlation with the 12-hour area under the time-concentration curve was the 4-hour area under the time-concentration curve on remission and relapse of the disease, followed by the 2-hour level after cyclosporin (c2) dosing in both disease states.

CONCLUSIONS

These data indicate that the same parameters used for cyclosporin therapeutic monitoring estimated during the nephrotic state can also be used during remission. Larger controlled studies are needed to confirm these findings.

Age effect on whole blood cyclosporine concentrations following oral administration in children with nephrotic syndrome

The aim of this study was to investigate age-related pharmacokinetic differences of cyclosporine (CyA) in children with nephrotic syndrome. Whole blood concentrations of CyA were monitored for a total of 96 times in 36 cases. The 25 male and 11 female patients ranged in age from 1.9 to 19.7 years with a mean age of 9.1 years. Renal biopsy showed minimal change in 33 patients and focal segmental glomerulosclerosis in three patients. CyA was orally administered in two divided doses just before meals. The doses of CyA administered were adjusted such that the target value for blood concentration at 2 h post-dose (C2) was 400-450 ng/ml. The 96 subjects were divided into three groups according to age: group I, 1-5 years (n = 30); group II, 6-10 years (n = 34); and group III, ≥ 11 years (n = 32). In all subjects, peak levels (Cmax) of CyA were reached at C1 or C2. There was no significant difference between the groups for C2, area under the whole blood concentration-time curve up to 4 h post-dose (AUC0-4), and Cmax. The mean CyA doses of groups I, II, and III were 4.8 ± 1.0 mg/kg/day, 3.8 ± 0.9 mg/kg/day, and 3.0 ± 0.6 mg/kg/day, respectively, and there were significant differences between every two groups. In addition, the dose-normalized Cmax (Cmax/dose) and AUC0-4 (AUC0-4/dose) values were significantly lower in the younger group than in the older group. These findings suggested that in children, when the same concentration is targeted, the required CyA dose would vary according to age but would be significantly higher for the younger children.

Cyclosporine A and steroid therapy in childhood steroid-resistant nephrotic syndrome

Background:

In children, idiopathic nephrotic syndrome (INS) is primarily treated using corticosteroids. When remission is not achieved, the coadministration of potent immunosuppressant therapy becomes imperative. Cyclosporine A (CsA) is reportedly associated with a higher incidence of remission in comparison with other immunosuppressive agents.

Methods:

The present study investigated the response of combination therapy using CsA and prednisolone in 30 Tunisian children with idiopathic steroid-resistant nephrotic syndrome (ISRNS). Renal histopathology was compatible with focal segmental glomerular sclerosis (FSGS) in 15 children, minimal change disease (MCD) in nine children, and diffuses mesangiale proliferation (DMP) in six children.

Results:

The therapy protocol produced a complete remission of proteinuria in 15 patients (50%) and a partial remission in nine patients (30%). Six patients (20%) showed no response to therapy. Progression to end stage renal disease occurred in five CsA-resistant children and in four CsA-responsive patients. CsA-related nephrotoxicity was detected by renal biopsy in one patient.

Conclusions:

CsA remains the primary cytotoxic treatment for childhood steroid-resistant nephrotic syndrome. Its use in combination with corticosteroids provides optimum efficiency without high risk of nephrotoxicity.

Therapeutic drug monitoring of cyclosporine microemulsion in interstitial pneumonia with dermatomyositis

The prognosis of dermatomyositis (DM)-associated progressive interstitial pneumonia (IP) has recently been improved by steroids/cyclosporine-A (CSA) combination therapy, but treatment outcomes varied. One reason for this variation is thought to be differences in CSA regimen. There is marked interpatient variability in CSA absorption. However, the pharmacokinetics of CSA has rarely been studied. In this study, we calculated the area under the blood concentration-time curve (AUC) of CSA microemulsion in 15 patients with progressive IP complicating DM, and analyzed its correlation with CSA levels at blood sampling time points to investigate the optimum monitoring and dosing regimen. The highest correlation between AUC(0-6) and blood level of CSA was observed 2 h (C2) after drug administration (R = 0.910). The trough level (C0) was not correlated with AUC(0-6) (R = 0.052). There were no differences in blood levels (AUC(0-6), C2, and C6) between postprandial administration in a divided dose (CSA given twice daily) and preprandial administration once daily in a single dose, while C0 was significantly lower (P = 0.020) when the drug was administered once daily before breakfast. These findings suggest that measurement of CSA blood level, especially C2 and C0, is useful to monitor clinical and adverse effects of CSA during combination therapy. It is also suggested that preprandial, once daily administration of CSA is beneficial in DM patients with progressive IP.