Altered Folate Homeostasis in Children with Down Syndrome: A Potential Basis for Enhanced Methotrexate Toxicity

Methotrexate for inflammatory skin disease in pediatric patients: Consensus treatment guidelines

Methotrexate (MTX) is a readily accessible drug, first used in 1948 and employed for a wide variety of indications since then. However, despite widespread off-label use, FDA labeling does not include approved indications for the use of MTX for many inflammatory skin diseases in pediatric patients, including morphea, psoriasis, atopic dermatitis, and alopecia areata, among others. Without published treatment guidelines, some clinicians may be hesitant to use MTX off-label, or uncomfortable prescribing MTX in this population. To address this unmet need, an expert consensus committee was convened to develop evidence- and consensus-based guidelines for use of MTX to treat pediatric inflammatory skin disease. Clinicians with experience and expertise in clinical research, drug development, and treating inflammatory skin disease in pediatric patients with MTX were recruited. Five committees were created based on major topic areas: (1) indications and contraindications, (2) dosing, (3) interactions with immunizations and medications, (4) adverse effects (potential for and management of), and (5) monitoring needs. Pertinent questions were generated and addressed by the relevant committee. The entire group participated in a modified Delphi process to establish agreement on recommendations for each question. The committee developed 46 evidence- and consensus-based recommendations, each with >70% agreement among members, across all five topics. These are presented in tables and text, along with a discussion of supporting literature, and level of evidence. These evidence- and consensus-based recommendations will support safe and effective use of MTX for the underserved population of pediatric patients who may benefit from this valuable, time-honored medication.

One-carbon pathway metabolites are altered in the plasma of subjects with Down syndrome: Relation to chromosomal dosage

Introduction

Down syndrome (DS) is the most common chromosomal disorder and it is caused by trisomy of chromosome 21 (Hsa21). Subjects with DS show a large heterogeneity of phenotypes and the most constant clinical features present are typical facies and intellectual disability (ID). Several studies demonstrated that trisomy 21 causes an alteration in the metabolic profile, involving among all the one-carbon cycle.

Methods

We performed enzyme-linked immunosorbent assays (ELISAs) to identify the concentration of 5 different intermediates of the one-carbon cycle in plasma samples obtained from a total of 164 subjects with DS compared to 54 euploid subjects. We investigated: tetrahydrofolate (THF; DS n = 108, control n = 41), 5-methyltetrahydrofolate (5-methyl-THF; DS n = 140, control n = 34), 5-formyltetrahydrofolate (5-formyl-THF; DS n = 80, control n = 21), S-adenosyl-homocysteine (SAH; DS n = 94, control n = 20) and S-adenosyl-methionine (SAM; DS n = 24, control n = 15).

Results

Results highlight specific alterations of THF with a median concentration ratio DS/control of 2:3, a decrease of a necessary molecule perfectly consistent with a chromosomal dosage effect. Moreover, SAM and SAH show a ratio DS/control of 1.82:1 and 3.6:1, respectively.

Discussion

The relevance of these results for the biology of intelligence and its impairment in trisomy 21 is discussed, leading to the final proposal of 5-methyl-THF as the best candidate for a clinical trial aimed at restoring the dysregulation of one-carbon cycle in trisomy 21, possibly improving cognitive skills of subjects with DS.

Red cell folate status among a subset of Canadian children with Down Syndrome post-fortification

BACKGROUND

Trisomy 21 or Down Syndrome (DS) is associated with altered methylation pathways. Children with DS may therefore represent a population subgroup with vulnerability to increased exposures to folic acid, which is involved in one-carbon metabolism. Folic acid (FA) fortification of flour and maternal FA supplementation are intended to reduce neural tube defects related to folate deficiency. The interventions have been widely successful in Canada. Emerging evidence suggests that higher FA exposures may also have potential negative consequences, including implications for DNA methylation. This retrospective chart review provides insight on the red blood cell (RBC) folate status of a subset of Canadian children and infants with DS, post-fortification.

METHODS

Children with DS in two Canadian provinces were assessed in the community. Access to RBC folate testing was variable, limiting sample size to 39 (n = 27 for children ≤6 years; n = 12 for children 6-18 years). All children with DS and an RBC folate result were included. The use of FA-containing supplements and formula was documented.

RESULTS

Among children 6-18 years, 100% had RBC folates >1000 nmol/L, 50% were >2000 nmol/L and 25% had levels above the upper laboratory reporting limit. Among the younger children (<6 years), 52% had RBC folates >2000 nmol and 2 children exceeded 3000 nmol/L. Among exclusively breast-fed infants (<12 months), 100% had RBC folates >1000 nmol/L and 50% had levels >2000 nmol/L, suggestive of in-utero or maternal exposures. RBC folate status among this subset of Canadian children with DS is higher than documented for the larger Canadian population, and higher than among US children with DS.

CONCLUSIONS

Young Canadian children with DS demonstrated high post-fortification RBC folate status. RBC folate status was higher than reported for the larger Canadian population, and higher than for US children with Down Syndrome. Consumption of folic acid-containing formula and/or supplements was relatively low among these Canadian children with DS, suggesting maternal FA supplements and/or FA-fortified foods may be important etiological factors. A larger, prospective study is needed to validate these results, and to explore potential health implications among this vulnerable population.

Landscape of germline cancer predisposition mutations testing and management in pediatrics: Implications for research and clinical care

As germline genetic testing capacities have improved over the last two decades, increasingly more people are newly diagnosed with germline cancer susceptibility mutations. In the wake of this growth, there remain limitations in both testing strategies and translation of these results into morbidity- and mortality-reducing practices, with pediatric populations remaining especially vulnerable. To face the challenges evoked by an expanding diversity of germline cancer mutations, we can draw upon a model cancer-associated genetic condition for which we have developed a breadth of expertise in managing, Trisomy 21. We can additionally apply advances in other disciplines, such as oncofertility and pharmacogenomics, to enhance care delivery. Herein, we describe the history of germline mutation testing, epidemiology of known germline cancer mutations and their associations with childhood cancer, testing limitations, and future directions for research and clinical care.

The First Reported Case of Juvenile Dermatomyositis in an Adolescent with Down Syndrome and the Clinical Considerations for Therapy

Background:

Down Syndrome (DS) is one of the most common birth conditions in the United States of America, with approximately 5300 births annually, resulting in an estimated birth prevalence of 12.6 per 10,000 live births and a population prevalence in the USA since 2010 of 6.7 per 10,000 inhabitants. Children with DS have complex medical challenges that present due to changes in their immune system that results in increased rates of infection, malignancy, and autoimmune disease. Juvenile Dermatomyositis (JDM) is a rare, autoimmune disease, and the most common inflammatory myopathy of childhood. Reports suggest an increased incidence of arthritis in children with DS, but there have been no reports of JDM in children with DS. Additionally, those with DS pose unique challenges with an increase in adverse effects and ineffectiveness of immunosuppressive therapy.

Case :

We describe the first case of an adolescent female with DS who developed JDM with a positive anti-p155/140 antibody and characteristic clinical phenotype. We discuss increased awareness of autoimmune disease in adolescents with DS and clinical considerations for therapy with immunosuppression.

Conclusion:

Adolescents with DS are at increased risk for autoimmune disease, including JDM. Awareness, early recognition of the signs and symptoms of autoimmune disease in those with DS is important, so appropriate therapy can be implemented.