Model-Informed individualized dosage regimen of sirolimus in pediatric patients with intractable lymphatic malformations.

Intractable lymphatic malformations (iLM) pose a significant threat to affected children, demonstrating limited responses to conventional treatments. Sirolimus, effectively inhibiting endothelial cell proliferation in lymphatic vessels, plays a crucial role in iLM treatment. However, the drug's narrow therapeutic window and substantial interindividual variability necessitate customized dosing strategies. This study aims to establish a Population Pharmacokinetic Model (PopPK model) for sirolimus in pediatric iLM patients, identifying quantitative relationships between covariates and sirolimus clearance and volume of distribution. Initial dosages are recommended based on a target concentration range of 5-15 ng/mL. Retrospective data from our institution, encompassing 53 pediatric patients with 275 blood concentration results over the past five years (average age: 4.64 ± 4.19 years), constituted the foundation of this analysis. The final model, adopting a first-order absorption and elimination single-compartment model, retained age as the sole covariate. Results indicated a robust correlation between apparent clearance (CL/F) at 5.56 L/h, apparent volume of distribution (V/F) at 292.57 L, and age. Monte Carlo simulation guided initial dosages for patients aged 0-18 years within the target concentration range. This study presents the first PopPK model using a large Therapeutic Drug Monitoring (TDM) database to describe personalized sirolimus dosing for pediatric iLM patients, contributing to pharmacokinetic guidance and potentially improving long-term clinical outcomes.

Endothelial Autophagy Promotes Atheroprotective Communication Between Endothelial and Smooth Muscle Cells via Exosome-Mediated Delivery of miR-204-5p.

BACKGROUND: Cellular communication among different types of vascular cells is indispensable for maintaining vascular homeostasis and preventing atherosclerosis. However, the biological mechanism involved in cellular communication among these cells and whether this biological mechanism can be used to treat atherosclerosis remain unknown. We hypothesized that endothelial autophagy mediates the cellular communication in vascular tissue through exosome-mediated delivery of atherosclerosis-related genes. METHODS: Rapamycin and adeno-associated virus carrying Atg7 short hairpin RNA under the Tie (TEK receptor tyrosine kinase) promoter were used to activate and inhibit vascular endothelial autophagy in high-fat diet-fed ApoE-/- mice, respectively. miRNA microarray, in vivo and in vitro experiments, and human vascular tissue were used to explore the effects of endothelial autophagy on endothelial function and atherosclerosis and its molecular mechanisms. Quantitative polymerase chain reaction and miRNA sequencing were performed to determine changes in miRNA expression in exosomes. Immunofluorescence and exosome coculture experiments were conducted to examine the role of endothelial autophagy in regulating the communication between endothelial cells and smooth muscle cells (SMCs) via exosomal miRNA. RESULTS: Endothelial autophagy was inhibited in thoracic aortas of high-fat diet-fed ApoE-/- mice. Furthermore, rapamycin alleviated high-fat diet-induced atherosclerotic burden and endothelial dysfunction, while endothelial-specific Atg7 depletion aggravated the atherosclerotic burden. miRNA microarray, in vivo and in vitro experiments, and human vascular tissue analysis revealed that miR-204-5p was significantly increased in endothelial cells after high-fat diet exposure, which directly targeted Bcl2 to regulate endothelial cell apoptosis. Importantly, endothelial autophagy activation decreased excess miR-204-5p by loading miR-204-5p into multivesicular bodies and secreting it through exosomes. Moreover, exosomal miR-204-5p can effectively transport to SMCs, alleviating SMC calcification by regulating target proteins such as RUNX2 (runt-related transcription factor 2). CONCLUSIONS: Our study revealed the exosomal pathway by which endothelial autophagy protects atherosclerosis: endothelial autophagy activation transfers miR-204-5p from endothelial cells to SMCs via exosomes, both preventing endothelial apoptosis and alleviating SMC calcification. REGISTRATION: URL: https://www.chictr.org.cn/; Unique identifier: ChiCTR2200064155.

Paclitaxel-coated versus sirolimus-coated balloon angioplasty for coronary artery disease: A systematic review and meta-analysis.

BACKGROUND: Although use of sirolimus-based analogs has shown superiority over paclitaxel in drug-eluting stents, the relative efficacy of these two agents released from drug-coated balloons (DCB) is unclear. The present meta-analysis is aimed to compare outcomes after percutaneous coronary intervention (PCI) with paclitaxel-coated balloons (PCB) versus sirolimus-coated balloons (SCB) for either in-stent restenosis or native de novo lesions. METHODS: The study outcomes were 1) target lesion failure (TLF), a composite of cardiac death, target vessel myocardial infarction, or target lesion revascularization, and 2) follow-up angiographic parameters including late lumen loss (LLL), diameter stenosis, and minimal lumen diameter (MLD). Pooled odds ratios (OR) and weighted mean differences (WMD) with 95% confidence intervals (CI) were calculated by using random-effects models. RESULTS: A search of PubMed, EMBASE, and Cochrane Library from their inception to January 2024 identified five randomized clinical trials and three observational studies with a total of 1861 patients (889 in PCB and 972 in SCB groups). During 9-12 months of follow-up, there was no significant difference in TLF (OR 1.01, 95% CI 0.75-1.35) between the two groups. On follow-up angiography at 6-9 months, MLD (WMD 0.10, 95% CI 0.02-0.17) was larger in PCB but there was no statistically significant difference in LLL (WMD -0.11, 95% CI -0.23-0.02) and diameter stenosis (WMD -3.33, 95% CI -8.11-1.45). CONCLUSIONS: Among patients undergoing DCB-only PCI, the risk of TLF was similar during 9-12 months of follow-up after PCB and SCB treatment. However, the MLD was larger favoring PCB over SCB on follow-up angiography.

Preparation and in vivo and ex vivo studies of sirolimus nano-in-situ gel ophthalmic formulation.

Sirolimus (SR) is a macrolide with antifungal and antitumor immunosuppressant properties, classified as a selective inhibitor of mammalian target of rapamycin (mTOR). In this study, an ionic in situ gel of SR (SR-SUS-ISG) was formulated using gellan gum, exhibiting stability regardless of temperature and pH variations, causing minimal irritation. Harnessing the physiological conditions of the eye, SR-SUS-ISG underwent gelation upon contact with ions, increasing drug viscosity and prolonging retention on the ocular surface. Concurrently, SR-SUS-ISG displayed favorable shear dilution properties, reducing viscosity at ambient temperature, enhancing fluidity, and facilitating convenient packaging and transport. Biocompatibility assessments on both human corneal epithelial cells and rabbit eyes demonstrated that SR-SUS-ISG could well be tolerated. Pharmacokinetic investigations in rabbit ocular aqueous humor revealed sustained release, improved corneal penetration, and enhanced bioavailability. Additionally, in a rat corneal alkali burn model, SR-SUS-ISG exhibited inhibitory effects on corneal neovascularization, associated with decreased levels of the inflammatory factors VEGF and MMPs. These findings suggested that SR-SUS-ISG held promise as an effective ocular drug delivery system.

Real-World Clinical Performance of a Novolimus-Eluting Stent Versus a Sirolimus-Eluting Stent.

INTRODUCTION: The DESyne novolimus-eluting coronary stent (NES) is a new-generation drug-eluting stent (DES) that is widely used, but clinical data are rarely reported for this stent. We compared the safety and effectiveness of the DESyne NES and the Orsiro bioresorbable polymer sirolimus-eluting stent (SES) in patients undergoing percutaneous coronary intervention (PCI). METHODS: This was a retrospective, single-center, observational study. Between July 2017 and December 2022, patients who presented with chronic or acute coronary syndrome undergoing PCI with DESyne NES or Orsiro SES were consecutively enrolled in the present study. The primary endpoint, major adverse cardiovascular event (MACE), was a composite of cardiovascular death, target-vessel myocardial infarction, or clinically driven target-lesion revascularization. RESULTS: A total of 776 patients (age 68.8 ± 12.2; 75.9% male) undergoing PCI were included. Overall, 231 patients with 313 lesions received NES and 545 patients with 846 lesions received SES. During a follow-up duration of 784 ± 522 days, the primary endpoint occurred in 10 patients (4.3%) in the NES group and in 36 patients (6.6%) in the SES group. After multivariate adjustment, the risk of MACE did not significantly differ between groups (NES vs. SES, hazard ratio 0.74, 95% CI, 0.35-1.55, p = 0.425). The event rate of individual components of the primary endpoint was comparable between the two groups. CONCLUSIONS: Favorable and similar clinical outcomes were observed in patients undergoing PCI with either NES or SES in a medium-term follow-up duration. Future studies with adequately powered clinical endpoints are required for further evaluation.

Outcomes With Limus- vs Paclitaxel-Coated Balloons for Percutaneous Coronary Intervention: Meta-Analysis of Randomized Controlled Trials.

BACKGROUND: Randomized controlled trials (RCTs) examining the outcomes with limus drug-coated balloons (DCBs) vs paclitaxel DCBs were small and underpowered for clinical endpoints. OBJECTIVES: This study sought to compare the angiographic and clinical outcomes with limus DCBs vs paclitaxel DCBs for percutaneous coronary intervention (PCI). METHODS: An electronic search of Medline, EMBASE, and Cochrane databases was performed through January 2024 for RCTs comparing limus DCBs vs paclitaxel DCBs for PCI. The primary endpoint was clinically driven target lesion revascularization (TLR). The secondary endpoints were late angiographic findings. Summary estimates were constructed using a random effects model. RESULTS: Six RCTs with 821 patients were included; 446 patients received a limus DCB, and 375 patients received a paclitaxel DCB. There was no difference between limus DCBs and paclitaxel DCBs in the incidence of TLR at a mean of 13.4 months (10.3% vs 7.8%; risk ratio [RR]: 1.32; 95% CI: 0.84-2.08). Subgroup analysis suggested no significant interaction among studies for de novo coronary lesions vs in-stent restenosis (Pinteraction = 0.58). There were no differences in the risk of major adverse cardiovascular events, cardiac mortality, or target vessel myocardial infarction between groups. However, limus DCBs were associated with a higher risk of binary restenosis (RR: 1.89; 95% CI: 1.14-3.12), late lumen loss (mean difference = 0.16; 95% CI: 0.03-0.28), and a smaller minimum lumen diameter (mean difference = -0.12; 95% CI: -0.22 to -0.02) at late follow-up. In addition, late lumen enlargement occurred more frequently (50% vs 27.5%; RR: 0.59; 95% CI: 0.45-0.77) with paclitaxel DCBs. CONCLUSIONS: Among patients undergoing DCB-only PCI, there were no differences in the risk of clinically driven TLR and other clinical outcomes between limus DCBs and paclitaxel DCBs. However, paclitaxel DCBs were associated with better late angiographic outcomes. These findings support the need for future trials to establish the role of new-generation limus DCBs for PCI.

Role of Sirolimus and Rituximab in the Treatment of Autoimmune Hepatitis.

Autoimmune hepatitis (AIH) is a rare chronic liver disease affecting annually 100,000-200,000 individuals in the United States. The first-line therapy in AIH is azathioprine and corticosteroids. However, adverse events may occur, which can preclude disease remission. In these cases, mycophenolate, mercaptopurine, and tacrolimus can be used. Rituximab is offered in difficult to treat cases. Sirolimus is an alternative regimen. However, little is known about its use in AIH. This is a challenging case of "difficult to treat" AIH managed with sirolimus and rituximab, after multiple unsuccessful trials with other medications.

Long-Term Outcomes Following Sirolimus-Coated Balloon or Drug-Eluting Stents for Treatment of In-Stent Restenosis.

BACKGROUND: Evidence suggests that drug-coated balloons may benefit in-stent restenosis (ISR) treatment. However, the efficacy of new-generation sirolimus-coated balloon (SCB) compared with the latest generation drug-eluting stents (DESs) has not been studied in this setting. METHODS: All patients in the EASTBORNE (The All-Comers Sirolimus-Coated Balloon European Registry) and DEB-DRAGON (DEB vs Thin-DES in DES-ISR: Long Term Outcomes) registries undergoing percutaneous coronary intervention for DES-ISR were included in the study. The primary study end point was target lesion revascularization at 24 months. Secondary end points were major adverse cardiovascular events, all-cause death, myocardial infarction, and target vessel revascularization at 24 months. Our goal was to evaluate the efficacy and safety of SCB versus thin-struts DES in ISR at long-term follow-up. RESULTS: A total of 1545 patients with 1679 ISR lesions were included in the pooled analysis, of whom 621 (40.2%) patients with 621 lesions were treated with thin-strut DES and 924 (59.8%) patients with 1045 lesions were treated with SCB. The unmatched cohort showed no differences in the incidence of target lesion revascularization (10.8% versus 11.8%; P=0.568); however, there was a trend toward lower rates of myocardial infarction (7.4% versus 5.0%; P=0.062) and major adverse cardiovascular events (20.8% versus 17.1%; P=0.072) in the SCB group. After propensity score matching (n=335 patients per group), there were no significant differences in the rates of target lesion revascularization (11.6% versus 11.8%; P=0.329), target vessel revascularization (14.0% versus 13.1%; P=0.822), myocardial infarction (7.2% versus 4.5%; P=0.186), all-cause death (5.7% versus 4.2%; P=0.476), and major adverse cardiovascular event (21.5% versus 17.6%; P=0.242) between DES and SCB treatment. CONCLUSIONS: In patients with ISR, angioplasty with SCB compared with thin-struts DES is associated with comparable rates of target lesion revascularization, target vessel revascularization, myocardial infarction, all-cause death, and major adverse cardiovascular events at 2 years.

A multi-step approach to overcome challenges in the management of head and neck lymphatic malformations, and response to treatment.

BACKGROUND: Lymphatic malformations are vascular developmental anomalies varying from local superficial masses to diffuse infiltrating lesions, resulting in disfigurement. Patients' outcomes range from spontaneous regression to severe sequelae notwithstanding appropriate treatment. The current classification guides, in part, clinicians through the decision-making process, prognosis prediction and choice of therapeutic strategies. Even though the understanding of molecular basis of the disease has been recently improved, a standardized management algorithm has not been reached yet. RESULTS: Here, we report our experience on five children with different lymphatic anomalies of the head and neck region treated by applying a multidisciplinary approach reaching a consensus among specialists on problem-solving and setting priorities. CONCLUSIONS: Although restitutio ad integrum was rarely achieved and the burden of care is challenging for patients, caregivers and healthcare providers, this study demonstrates how the referral to expert centres can significantly improve outcomes by alleviating parental stress and ameliorating patients' quality of life. A flow-chart is proposed to guide the multidisciplinary care of children with LMs and to encourage multidisciplinary collaborative initiatives to implement dedicated patients' pathways.

Infection risk in patients with autoimmune cytopenias and immune dysregulation treated with mycophenolate mofetil and sirolimus.

Introduction: Autoimmune cytopenias (AICs) are a group of disorders characterized by immune-mediated destruction of blood cells. In children, they are often secondary to immune dysregulation that may require long-lasting immunosuppression. Mycophenolate mofetil and sirolimus represent two well-tolerated options to treat these disorders, often as a steroid-sparing option. However, no data are available on the infection risk for patients undergoing long-lasting treatments. Patients and methods: The rate of severe infective events was calculated in episodes per 100 persons/months at risk (p/m/r) documented by the analysis of hospitalization charts between January 2015 and July 2023 of patients treated with mycophenolate mofetil or sirolimus given for isolated AIC or AICs associated with autoimmune lymphoproliferative syndrome (ALPS)/ALPS-like syndromes in two large Italian pediatric hematology units. Results: From January 2015 to July 2023, 13 out of 96 patients treated with mycophenolate mofetil or sirolimus developed 16 severe infectious events requiring hospitalization. No patients died. Overall infection rate was 0.24 person/*100 months/risk (95% CI 0.09-0.3). Serious infectious events incidence was higher in patients with ALPS-like compared to others (0.42 versus 0.09; p = 0.006) and lower in patients who underwent mycophenolate treatment alone compared to those who started sirolimus after mycophenolate failure (0.04 versus 0.29, p = 0.03). Considering only patients who started treatment at the beginning of study period, overall cumulative hazard was 18.6% at 60 months (95% CI 3.4-31.4) with higher risk of infectious events after 5 years in ALPS-like patients (26.1%; 95% CI 3.2-43.5) compared to other AICs (4%; 95% CI 0-11.4; p = 0.041). Discussion: To the best of our knowledge, this is the first study to describe the infectious risk related to mycophenolate and sirolimus chronic treatment in patients with AICs and immune dysregulation. Our data highlight that infection rate is very low and mainly related to the underlying hematological condition. Conclusions: Mycophenolate and sirolimus represent a safe immunosuppressive therapy in AICs and immune dysregulation syndromes.

Sirolimus Use in Refractory Crohn's Disease.

Treatment options for patients with inflammatory bowel disease are constantly evolving; however, medication-refractory disease remains an issue. Pediatric case series show the potential benefit of sirolimus therapy in refractory Crohn's disease (CD); however, limited data exist in adult patients. As such, we retrospectively identified and report clinical outcomes for 4 patients prescribed sirolimus for treatment of refractory CD. Despite a median sirolimus therapy duration of 524 days and some therapeutic benefits, all patients discontinued therapy due to adverse effects. Our findings suggest that while sirolimus may have clinical utility, its role may be limited by treatment-derived adverse effects.

Comparison of whole-blood sirolimus concentrations measured by EMIT-based Siemens Viva-ProE® System and LC-MS/MS in Chinese transplant patients.

Sirolimus (SRL) is commonly used in transplant patients to prevent organ transplant rejection. The current guidelines recommend to perform SRL therapeutic drug monitoring regularly to improve treatment outcomes and avoid adverse effects. Consequently, a precise and accurate method for determining SRL is crucial in clinical practice. Currently, liquid chromatography-tandem mass spectrometry (LC-MS/MS) and immunoassays have been widely adopted for determining SRL concentrations. However, previous studies have shown that immunoassays exhibit a positive bias compared to LC-MS/MS. As the new updated version of the EMIT-based Viva-E® System (SVPS), this study aims to compare SRL blood concentrations measured by the SVPS and LC-MS/MS. The residual whole-blood samples obtained from transplant patients were simultaneously analyzed using the SVPS and LC-MS/MS, respectively. The correlation between the two assays was analyzed using the linear regression analysis and Deming linear regression. The Pearson correlation coefficient and Intraclass correlation coefficient (ICC) analysis were executed. The Paired Wilcoxon test and Bland-Altman analysis were performed to assess the concordance between the two methods. The SVPS considerably increased SRL concentration value by 46.62 % as compared to the LC-MS/MS method. When SRL concentrations measured by the SVPS were above 4.0 ng/mL, there was no significant difference between the corrected SVPS concentrations after using the Deming linear regression equation, indicating their interchangeability. Given the significant disparities observed between EMIT and LC-MS/MS, it is crucial to indicate the methodology and instruments in both TDM reports and future clinical guidelines. Our study also provides the conversion formulas between the SVPS and LC-MS/MS, which can be applied as a reference for different clinical centers.

Evaluation of off-label rapamycin use on oral health.

Rapamycin (sirolimus) is an FDA approved drug with immune modulating properties that is being prescribed off-label in adults as a preventative therapy to maintain healthspan. We recently published one of the first reports on 333 adults with a history of off-label rapamycin use. Along with presenting evidence that rapamycin can be used safely in adults of normal health status, we discovered that about 26% of rapamycin users also reported oral health changes. Given the recent evidence highlighting the potential benefits of rapamycin and its derivatives in enhancing oral health, we conducted a secondary data analysis to profile the oral health of off-label rapamycin users, the true incidence of mouth sores, and present specific case studies of periodontal bone loss quantification using an FDA-approved artificial intelligence platform. Contrary to expected findings and previous literature, dimensions of rapamycin usage (such as length of use, dosage, and interval) were not found to be related to the incidence of mouth ulcers in rapamycin users. Notably, among rapamycin users, the most deleterious forms of ulcers were found to be infrequent and not statistically linked to rapamycin usage, with most rapamycin users having a common transient form of mouth ulcers. Additionally, we describe the general oral health outcomes of off-label rapamycin users and provide recommendations for individuals engaging in off-label rapamycin to be regularly checked by a dentist or an oral health care provider. This report was limited by being a secondary data analysis taken from survey data that focused on a more holistic health model. Future studies will use a focused survey that collects data on more dimensions of oral health outcomes while including questions on oral health for non-rapamycin-using participants.

Effectiveness and safety of liposomal rapamycin for the treatment of facial angiofibromas in tuberous sclerosis.

AIM: Topical rapamycin is the pharmacological treatment of choice for facial angiofibromas in rare tuberous sclerosis disease. A new, more advanced, and complex formula was developed in our pharmacy service: rapamycin 0.4% liposomal formulation, with better organoleptic characteristics and a more favorable release profile of the active ingredient. The purpose of this study is to evaluate the effectiveness and safety of liposomal topical rapamycin for the treatment of facial injuries in this rare disease. METHOD: This was an observational, prospective, and multicenter study. Effectiveness was evaluated mainly through facial angiofibromas severity index (FASI), investigator's global assessment (IGA) scores, and dermatology life quality index (DLQI) questionnaire. To assess the safety profile of rapamycin, adverse reactions were reported, and blood tests and blood rapamycin levels were performed during treatment. RESULTS: Eleven patients were included, of which 8/11 (73%) patients obtained successful treatment according to FASI and IGA scores after 24 weeks of treatment. Statistical analysis demonstrated a significant improvement (p<.05) in FASI and IGA scores, erythema, and FA size after treatment with rapamycin liposomal formulation (FASI before treatment, median (interquartile range): 6.0 (2.0), FASI after treatment: 3.5 (2.0), p=.0063). Five patients also improved their quality of life after treatment. Regarding safety profile of rapamycin, the most common adverse reaction was mild pruritus and 2 patients reported erythema, who discontinued treatment prematurely. All hematological tests were normal, and blood rapamycin levels were undetectable. CONCLUSIONS: After galenic improvements and clinical evaluations, the rapamycin liposomal formulation proved to be effective and safe for this therapeutic indication. This new formulation was included as a magistral formula in our hospital pharmacy service, now accessible for prescribing by dermatologists. Drug development in hospital pharmacy is often the only pharmacological alternative available to treat the symptoms of rare diseases, when treatment options are limited or inadequate.

Treatment experience for different risk groups of Kaposiform hemangioendothelioma.

Background: Kaposiform hemangioendothelioma (KHE) is a rare vascular tumor with a high risk of mortality. Few studies with large samples of KHE have been reported. KHE may develop into the Kasabach-Merritt phenomenon (KMP), which is characterized by thrombocytopenia and consumptive coagulopathy. The features of severe symptomatic anemia and life-threatening low platelets make the management of KHE associated with KMP challenging. Objective: The aim of this study was to examine the clinical characteristics of patients with KHE and discuss the treatment experience for different risk groups of KHE. Methods: Through a retrospective review of 70 patients diagnosed with KHE between 2017 and 2022 in our center, we classify lesions into three clinicopathological stages based on the tumor involving depth, and divided the severity of KHE into three levels by estimating clinicopathological stages and severity of thrombocytopenia. Treatments of different severity groups were estimated with sufficient data. Results: In our cohort, 27% were neonates, and KHE lesion occurred at birth in 84% of patients. There was a slight male predominance (32 girls and 38 boys). Common clinical characteristics included associated coagulation disorder (100%), locally aggressive cutaneous blue-purple mass (89%), thrombocytopenia (78%), and local pain or joint dysfunction (20%). The lower extremities were the dominant location (35%), followed by the trunk (29%), the maxillofacial region and neck (24%), and the upper extremities (10%). Of the total cohort, 78% developed KMP; the median age at which thrombocytopenia occurred was 27.8 days. The median platelet count of patients who were associated with KMP was 24,000/µL in our cohort. Ninety-two percent of patients were given surgery treatment and 89% of these patients were given high-dose methylprednisolone (5-6 mg/kg daily) before surgery. In 55 patients with KMP, 36% were sensitive to high-dose corticosteroid therapy. Patients from the low-risk group (eight cases) underwent operation, all of whom recovered without recurrence after a maximum follow-up of 5 years. Out of 26 patients from the high-risk group, 25 underwent surgery treatment, with 1 case undergoing secondary surgery after recurrence and 1 case taking sirolimus. Out of 36 cases from the extremely high-risk group, 32 underwent surgery (including 2 cases who underwent external carotid artery ligation and catheterization), 3 of whom underwent secondary operation after recurrence, and the remaining 4 cases took medicine. The mean length of having sirolimus was 21 months; two cases stopped taking sirolimus due to severe pneumonia. Two cases died at 1 and 3 months after discharge. Conclusions: Our study describes the largest assessment of high-risk patients with KHE who have undergone an operation to date, with 5 years of follow-up to track recovery, which provides invaluable knowledge for the future treatment of patients with KHE and KMP from different risk groups: Early surgical intervention may be the most definitive treatment option for most patients with KHE; multimodality treatment is the best choice for the extremely high-risk group.

Acneiform Eruptions Possibly Triggered by Clarithromycin During Sirolimus Treatment.

Acneiform eruption is the recognized dermatological side effect of sirolimus, an inhibitor of the mammalian target of rapamycin, although the pathophysiological mechanisms and dose dependency of this side effect remain unclear. This case report describes a case of a 40-year-old Japanese woman treated with systemic sirolimus who developed acneiform eruptions following the administration of clarithromycin. The acneiform eruption resolved after discontinuation of sirolimus and relapsed with the resumption. Since sirolimus and clarithromycin have a potential drug-drug interaction mediated by cytochrome P450 3A (CYP3A), this case suggests that the acneiform eruption developed in association with elevated blood levels of sirolimus. We conclude that clinicians should be aware of the possibility of developing acneiform eruption during sirolimus treatment, especially when administered with medications that inhibit CYP3A.