Response to sirolimus in capillary lymphatic venous malformations and associated syndromes: Impact on symptomatology, quality of life, and radiographic response

BACKGROUND

Capillary lymphatic venous malformations (CLVM) and associated syndromes, including Klippel-Trenaunay syndrome (KTS) and congenital lipomatous overgrowth, vascular malformation, epidermal nevi, skeletal, and spinal syndrome (CLOVES), are underrecognized disorders associated with high morbidity from chronic pain, recurrent infections, bleeding, and clotting complications. The rarity of these disorders and heterogeneity of clinical presentations make large-scale randomized clinical drug trials challenging. Identification of PIK3CA (phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit alpha [gene]) mutations in CLVM has made targeted medications, such as sirolimus, attractive treatment options. The aim of this study was to investigate the safety and efficacy of sirolimus therapy in CLVM.

PROCEDURE

A combined prospective and retrospective cohort of pediatric and young adult patients with CLVM treated with sirolimus was evaluated for disease response, including symptom improvement, quality of life (QOL), and radiologic response. Sirolimus dosing regimens and toxicities were also assessed.

RESULTS

Twenty-nine patients with CLVM, including KTS and CLOVES, were included. Ninety-three percent of patients reported improved QOL, and 86% had improvement in at least one symptom. Most significantly, improvement was noted in 100% of patients with bleeding and 89% with thrombotic complications with corresponding decreases in mean D-dimer (p = .008) and increases in mean fibrinogen (p = .016). No patients had progressive disease on sirolimus. Most common side effects included neutropenia, lymphopenia, infection, and aphthous ulcers/stomatitis. No toxicities were life-threatening, and none required long-term discontinuation of sirolimus.

CONCLUSION

Sirolimus appears to be effective at reducing complications and improving QOL in patients with CLVM and associated syndromes. In this patient cohort, sirolimus was well tolerated and resulted in few treatment-related toxicities.

A novel case of prolonged Ifosfamide encephalopathy and long-term treatment with methylene blue: a case report and review of literature

Background

Encephalopathy following Ifosfamide treatment is a well-described phenomenon that is typically treated with Methylene Blue (MB). Chloroacetaldehyde, a potentially neurotoxic metabolite of Ifosfamide is hypothesized to cause this encephalopathy. Current guidelines for treatment is to stop Ifosfamide and provide supportive care. MB acts to inhibit Chloroacetaldehyde formation and has been described as a therapy and prophylaxis for Ifosfamide-encephalopathy. MB is effective within 30 min and lasts up to 3 days. Prolonged encephalopathy and MB therapy has not been described in the literature as lasting longer than 30 days following treatment.

Case presentation

We present the case of an 11-year-old female with autistic spectrum disorder and recurrent episodes of severe somnolence for 7 months following Ifosfamide therapy for her Non-Germinomatous Germ Cell Tumor (GCT). Periods of somnolence occurred prior to receiving cranial RT. Administration of MB gave immediate but limited response, with resolution of somnolence lasting 1-2 days between administrations. The somnolence could not be explained by neuroimaging or laboratory evaluation, but EEG indicated persistent encephalopathy.

Conclusion

A literature review determines that neurotoxicity is a side effect of Ifosfamide, but this effect has not been described persisting longer than 30 days. Our case continued to require treatment with MB for 7 months following cessation of therapy. We report these novel clinical findings, and hypothesize that there could be a genetic/metabolic component linking this reaction to Ifosfamide with the case patient’s pre-existing autism. This possible association may also correlate to the already-established link between autism and the development of GCTs. This hypothesis leads to further discussion on the suitable usage of Ifosfamide in children with co-morbidities and the necessity of screening prior to its usage.

Novel mutation in the MYH2 gene in a symptomatic neonate with a hereditary myosin myopathy

INTRODUCTION

Hereditary myosin myopathies are muscle disorders caused by mutations in myosin heavy chain genes. The MYH2 gene encodes the fast 2A skeletal muscle isoform, and mutations manifest as joint contractures, muscle weakness, and external ophthalmoplegia. Muscle biopsy shows decreased type 2A fibers, and vacuoles are sometimes present in adults with progressive disease.

PRESENTATION OF CASE

This case describes a full term baby boy with hypotonia, dysmorphic features, dysphagia, and aspiration. Whole genome sequencing detected a novel heterozygous variant in the MYH2 gene. Muscle biopsy showed decreased type 2A fibers and vacuoles in myofibers.

DISCUSSION

Hypotonia and dysphagia are common in infants with a MYH2 myopathy. However, dysmorphic features and vacuoles on biopsy have not previous been described in infants with MYH2 myopathies.

CONCLUSION

This case reports an unusual phenotype of a rare neonatal-onset congenital myopathy associated with a novel heterozygous variant in MYH2.

Neonatal lung ultrasound exam guidelines

Point-of-care ultrasound (POC-US) is increasingly used especially in emergency and critical-care medicine. It is focused, quick and does not expose patients to ionizing radiation. It encompasses all organ systems and has well-defined indications. Lung ultrasound (LUS) represents one of the most exciting applications in the field of POC-US. It is particularly important to emphasize the role of LUS in neonatology due to the specific pathology inherent in lung immaturity as well as in the particular sensitivity of neonates to repeated radiation exposure. One of the main barriers to the more extensive use of the ultrasound technology is a lack of efficient and attractive training solutions followed by the structured quality-check assurance. In an effort to help bridge this gap, based on the most current literature, we developed creative and intuitive neonatal LUS algorithms. We hope they can serve as a clinical imaging guidelines and a valuable complement to the history and physical exam.

Transfusion related iron overload in pediatric oncology patients treated at a tertiary care centre and treatment with chelation therapy

We conducted a retrospective chart review to determine prevalence of, risk factors for, and liver toxicity associated with Transfusion Related Iron Overload (TRIO) in pediatric cancer patients, and report our experience with Iron Chelation Therapy (ICT). Total number of transfusions was identified as the major risk factor, with a prevalence of 37% in patients receiving ≥10 transfusions. Four patients with TRIO and abnormal liver function tests (LFT) received ICT. Significant decrease in serum ferritin and improvement in LFT were observed, with no serious adverse effects from ICT noted. Guidelines for screening and treatment of TRIO in pediatric oncology are needed.

Vascular endothelial growth factor blockade rapidly elicits alternative proangiogenic pathways in neuroblastoma

Most children with neuroblastoma presenting after infancy have metastatic, chemoresistant disease. Amplification of the MYCN proto-oncogene is a significant marker of these poor-prognosis neuroblastoma tumors. Recent studies suggest that MYCN may function in part by promoting angiogenesis via vascular endothelial growth factor (VEGF). VEGF blockade has been validated as a therapeutic strategy in adult cancers. In these studies, we asked whether inhibition of VEGF signaling via VEGFR2 blockade in established MYCN-amplified neuroblastoma xenografts would: 1) restrict tumor growth; 2) induce hypoxia; and 3) alter tumor vasculature. The MYCN-amplified neuroblastoma human cell line NGP was implanted intrarenally in athymic female mice. After 5 weeks, mice with established tumors were selected, a cohort euthanized to provide day 0 controls, and the rest assigned to receive biweekly injections of DC101 (anti-murine VEGFR2 antibody) or vehicle. DC101 treatment did not inhibit progressive tumor growth in established NGP xenografts. Although tumor vasculature was not significantly disrupted, a modest increase in tumor hypoxia was demonstrated by pimonidazole staining, and expression of a previously described hypoxia metagene was increased by gene set enrichment analysis (GSEA) in DC101-treated tumors. DC101 treatment elicited increased: 1) expression of VEGFR1 and its ligand placental growth factor; and 2) increased Notch activation in tumor vasculature concurrent with expression of the Notch ligand Jagged1. This result suggests that established MYCN-amplified neuroblastoma tumors are relatively VEGF-independent, and display the ability to rapidly up-regulate hypoxia-responsive alternative proangiogenic mechanisms that may stabilize vasculature when VEGF is deficient.

Angiopoietin-1/Tie-2 activation contributes to vascular survival and tumor growth during VEGF blockade

Approval of the anti-vascular endothelial growth factor (VEGF) antibody bevacizumab by the FDA in 2004 reflected the success of this vascular targeting strategy in extending survival in patients with advanced cancers. However, consistent with previous reports that experimental tumors can grow or recur during VEGF blockade, it has become clear that many patients treated with VEGF inhibitors will ultimately develop progressive disease. Previous studies have shown that disruption of VEGF signaling in tumors induces remodeling in surviving vessels, and link increased expression of angiopoietin-1 (Ang-1) with this process. However, overexpression of Ang-1 in different tumors has yielded divergent results, restricting angiogenesis in some systems while promoting it in others. These data raise the possibility that effects of Ang-1/Tie-2 may be context-dependent. Expression of an Ang-1 construct (Ang1*) did not significantly change tumor growth in our model prior to treatment, although vessels exhibited changes consistent with increased Tie-2 signaling. During inhibition of VEGF, however, both overexpression of Ang1* and administration of an engineered Ang-1 agonist (Bow-Ang1) strikingly protected tumors and vasculature from regression. In this context, Ang-1/Tie-2 activation limited tumor hypoxia, increased vessel caliber, and promoted recruitment of mural cells. Thus, these studies support a model in which activation of Tie-2 is important for tumor and vessel survival when VEGF-dependent vasculature is stressed. Understanding such mechanisms of adaptation to this validated form of therapy may be important in designing regimens that make the best use of this approach.

The use of DNA markers for carrier detection and prenatal diagnosis of haemophilia A in Egyptian families

Haemophilia A is the most common inherited X-linked recessive bleeding disorder. The aim was to investigate the usefulness of two DNA markers in linkage analysis, one intragenic BCL1 affecting restriction site in intron 18, and is detected as restriction fragment length polymorphism (RFLP), and one extragenic variable number of tandem repeat (VNTR) locus DXS52 (St14) to formulate an informative and accurate carrier detection and prenatal diagnosis. The study included 46 families with at least one child affected with haemophilia A, and 30 unrelated normal females as control group. Polymerase chain reaction (PCR) and restriction enzyme analysis were used to study the polymorphism in BCL1, and long-distance PCR for detection of VNTR (ST14) alleles. The incidence of BCL1 (+) allele was 74%, 72% and 60% in patients, mothers and control group, respectively. Expected heterozygosity for BCL1 was 40% in mothers of affected cases compared with 48% in the female control group. However, observed heterozygosity was found to be 48% in the mothers of affected cases, compared with 60% in the control group. Thus, 48% of the studied families are informative for this marker alone. Nine different alleles of VNTR (St14) were observed in mothers and six alleles in affected cases and six in the control group. The most prevalent alleles were 1300 bp (45.5% and 34%) and 700 bp (13.6% and 20%) in patients and their mothers, respectively. Observed heterozygosity in mothers was 41% compared with 43.3% in controls. The combined use of both BCL1 and St14 markers raised the informative rate to 63.6%. Carrier detection and prenatal diagnosis is possible in haemophilia A families using both DNA markers. We suggest screening haemophilic families first for BCL1 polymorphism followed by analysis of St14 locus.

Transcription factors of the anterior neural plate alter cell movements of epidermal progenitors to specify a retinal fate

The embryonic progenitors that give rise to the vertebrate retina acquire their cell fate identity through a series of transitions that ultimately determine their final, differentiated retinal cell fates. In Xenopus, these transitions have been broadly defined as competence, specification, and determination. The expression of several transcription factors within the anterior neural plate at the time when the presumptive eye field separates from other neural derivatives suggests that these genes function to specify competent embryonic progenitors toward a retinal fate. In support of this, we demonstrate that some transcription factors expressed in the anterior neural ectoderm and/or presumptive eye field (otx2, pax6, and rx1) change the fate of competent, ventral progenitors, which normally do not contribute to the retina, from an epidermal to a retinal fate. Furthermore, the expression of these factors changes the morphogenetic movements of progenitors during gastrulation, causing ventral cells to populate the native anterior neural plate. In addition, we experimentally demonstrate that the efficacy of pax6 to specify retinal cells depends on the position of the affected cell relative to the field of neural induction. Thereby, otx2, pax6, and rx1 mediate early steps of retinal specification, including the regulation of morphogenetic cell movements, that are dependent on the level of neural-inductive signaling.

Earthquakes: health outcomes and implications in Lebanon

Earthquakes remain damaging to human life and property. Recent reports point out that there is 50% chance to have a damaging earthquake in the next 50 years in Lebanon. Major health outcomes of earthquakes include physical injuries, cardiovascular effects and psychological reactions. Physical injuries are correlated with entrapment, higher number of floors in buildings and behavior at time of impact. Cardiovascular effects of earthquakes are either immediate or delayed. Immediate cardiovascular effects are exemplified by increased coronary death while delayed effects are reflected by the increase in coronary risk factors such as serum triglycerides and heart rate. The severity of PTSD decreases as the distance from the epicenter of the earthquake increases. Preventive measures such as implementation of safety building codes, medical emergency readiness and public education should be carried out in areas threatened by earthquakes. Also special mental health programs should be executed following an earthquake.