Plasma C24:0- and C26:0-lysophosphatidylcholines are reliable biomarkers for the diagnosis of peroxisomal ß-oxidation disorders.

The gold-standard diagnostic test for peroxisomal disorders (PDs) is plasma concentration analysis of very long-chain fatty acids (VLCFAs). However, this method's time-consuming nature and limitations in cases which present normal VLCFA levels necessitates alternative approaches. The analysis of C26:0-lysophosphatydylcholine (C26:0-LPC) in dried blood spot samples by tandem-mass spectrometry (MS/MS) has successfully been implemented in certain newborn screening programs to diagnose X-linked adrenoleukodystrophy (ALD). However, the diagnostic potential of very long-chain LPCs concentrations in plasma remains poorly understood. This study sought to evaluate the diagnostic performance of C26:0-LPC and other very long-chain LPCs, comparing them to VLCFA analysis in plasma. The study, which included 330 individuals affected by a peroxisomal ß-oxidation deficiency and 407 control individuals, revealed that C26:0- and C24:0-LPC concentrations demonstrated the highest diagnostic accuracy (98.8% and 98.4%, respectively), outperforming VLCFA when C26:0/C22:0 and C24:0/C22:0 ratios were combined (98.1%). Combining C24:0- and C26:0-LPC gave the highest sensitivity (99.7%), with ALD females exhibiting notably higher sensitivity compared with the VLCFA ratio combination (98.7% vs. 93.5%, respectively). In contrast, C22:0-LPC exhibited suboptimal performance, primarily due to its low sensitivity (75%), but we identified a potential use to help distinguish between ALD and Zellweger spectrum disorders. In summary, MS/MS analysis of plasma C24:0- and C26:0-LPC concentrations represents a rapid and straightforward approach to diagnose PDs, demonstrating superior diagnostic accuracy, particularly in ALD females, compared with conventional VLCFA biomarkers. We strongly recommend integrating very-long chain LPC plasma analysis in the diagnostic evaluation of individuals suspected of having a PD.

The experiences of parents of children diagnosed with cerebral adrenoleukodystrophy.

BACKGROUND: Adrenoleukodystrophy (ALD) is a rare X-linked neurodegenerative disease, affecting the brain, spinal cord and adrenal cortex. Childhood cerebral ALD (CCALD) is the most severe form of disease, involving rapidly progressive neurological deterioration. The treatment option for CCALD is allogenic haemopoietic stem cell transplant, which is only successful for early-stage disease. Parents' experiences of CCALD can inform healthcare delivery. STUDY AIM: To detail the experiences of parents of children diagnosed with cerebral ALD. METHODS: A descriptive qualitative study. Parents were recruited via a UK-based community support organisation. Data collection involved single semi-structured interviews structured around a topic guide and conducted remotely. Data were analysed using the thematic analysis approach. FINDINGS: Twelve parents from 11 families with a total of 16 children with ALD contributed to the study. Their 16 children with ALD followed one of three disease pathways, determined by the extent of neurological damage at diagnosis. Three themes, and their respective sub themes, describe the pathways and what they meant for parents. 'No possibility of treatment' concerns situations when CCALD was diagnosed at an advanced stage, the landslide of deterioration parents witnessed and their efforts to maintain normality. 'Close to the treatment threshold' describes situations where a small treatment window required parents to make agonising treatment decisions. 'Watching and waiting' explains the challenges for parents when disease was detected early enabling children to benefit from timely treatment. DISCUSSION: Parents' experiences were largely defined by the extent of cerebral damage at diagnosis, which determined the availability and success of treatment. There were specific challenges related to the three situations, indicating areas where support from health and care services may help parents deal with this devastating diagnosis. CONCLUSION: This study indicates support needs of parents across the spectrum of CCALD diagnoses and highlights the critical importance of early diagnosis.

VUS: Variant of uncertain significance or very unclear situation?

The advancements in population screening, including newborn screening, enables the identification of disease-causing variants and timely initiation of treatment. However, screening may also identify mild variants, non-disease variants, and variants of uncertain significance (VUS). The identification of a VUS poses a challenge in terms of diagnostic uncertainty and confusion. X-linked adrenoleukodystrophy (ALD) serves as an illustrative example of this complex issue. ALD is a monogenic neurometabolic disease with a complex clinical presentation and a lack of predictive tests for clinical severity. Despite the success of ALD newborn screening, a significant proportion (62%) of missense variants identified through newborn screening exhibit uncertainty regarding their pathogenicity. Resolving this issue requires ongoing efforts to accurately classify variants and refine screening protocols. While it is undisputable that ALD newborn screening greatly benefits boys with the disease, the identification of VUS underscores the need for continuous research and collaboration in improving screening practices.

Newborn screening for adrenoleukodystrophy: International experiences and challenges.

X-linked adrenoleukodystrophy (XALD) is the most common leukodystrophy. It has an estimated incidence of around 1/17.000, and a variable phenotype. Following the passage of Aidens Law, New York became the first state to implement a newborn screening for XALD in 2013. Since then, 38 American states, Taiwan, and the Netherlands have included XALD in their NBS program, and Japan and Italy have ongoing pilot studies. Screening for XALD allows for early, potentially lifesaving treatment of adrenal insufficiency and cerebral demyelination but is also a complex subject, due to our limited understanding of the natural history and lack of prognostic biomarkers. Screening protocols and algorithms vary between countries and states, and results and experiences gained so far are important for the future implementation of XALD NBS in other countries. In this review, we have examined the algorithms, methodologies, and outcomes used, as well as how common challenges are addressed in countries/states that have experience using NBS for XALD. We identified 14 peer-reviewed reports on NBS for XALD. All studies presented methods for detecting XALD at birth by NBS using a combination of mass spectrometry and ABCD1 gene sequencing. This has allowed for early surveillance of presymptomatic XALD patients, and the possibility for early detection and timely treatment of XALD manifestations. Obstacles to NBS for XALD include how to deal with variants of unknown significance, whether to screen females, and the ethical concerns of an NBS for a disease where we have limited understanding of natural history and phenotype/genotype correlation.

Dicarboxylic acylcarnitine biomarkers in peroxisome biogenesis disorders.

The peroxisome is an essential eukaryotic organelle with diverse metabolic functions. Inherited peroxisomal disorders are associated with a wide spectrum of clinical outcomes and are broadly divided into two classes, those impacting peroxisome biogenesis (PBD) and those impacting specific peroxisomal factors. Prior studies have indicated a role for acylcarnitine testing in the diagnosis of some peroxisomal diseases through the detection of long chain dicarboxylic acylcarnitine abnormalities (C16-DC and C18-DC). However, there remains limited independent corroboration of these initial findings and acylcarnitine testing for peroxisomal diseases has not been widely adopted in clinical laboratories. To explore the utility of acylcarnitine testing in the diagnosis of peroxisomal disorders we applied a LC-MS/MS acylcarnitine method to study a heterogenous clinical sample set (n = 598) that included residual plasma specimens from nineteen patients with PBD caused by PEX1 or PEX6 deficiency, ranging in severity from lethal neonatal onset to mild late onset forms. Multiple dicarboxylic acylcarnitines were significantly elevated in PBD patients including medium to long chain (C8-DC to C18-DC) species as well as previously undescribed elevations of malonylcarnitine (C3-DC) and very long chain dicarboxylic acylcarnitines (C20-DC and C22-DC). The best performing plasma acylcarnitine biomarkers, C20-DC and C22-DC, were detected at elevated levels in 100% and 68% of PBD patients but were rarely elevated in patients that did not have a PBD. We extended our analysis to residual newborn screening blood spot cards and were able to detect dicarboxylic acylcarnitine abnormalities in a newborn with a PBD caused by PEX6 deficiency. Similar to prior studies, we failed to detect substantial dicarboxylic acylcarnitine abnormalities in blood spot cards from patients with x-linked adrenoleukodystrophy (x-ald) indicating that these biomarkers may have utility in quickly narrowing the differential diagnosis in patients with a positive newborn screen for x-ald. Overall, our study identifies widespread dicarboxylic acylcarnitine abnormalities in patients with PBD and highlights key acylcarnitine biomarkers for the detection of this class of inherited metabolic disease.

Neonatal lupus is a novel cause of positive newborn screening for X-linked adrenoleukodystrophy.

We report three unrelated individuals, each exposed to maternal autoantibodies during gestation and found to have elevated very long-chain fatty acids (VLCFAs) in the newborn period after screening positive by California newborn screening (NBS) for X-linked adrenoleukodystrophy (ALD). Two probands presented with clinical and laboratory features of neonatal lupus erythematosus (NLE); the third had features suggestive of NLE and a known maternal history of Sjogren's syndrome and rheumatoid arthritis. In all three individuals, subsequent biochemical and molecular evaluation for primary and secondary peroxisomal disorders was nondiagnostic with normalization of VLCFAs by 15 months of age. These cases add to the expanding differential diagnosis to consider in newborns who screen positive for ALD via elevated C26:0-lysophosphatidylcholine. Though the pathophysiology of how transplacental maternal anti-Ro antibodies damage fetal tissue is not well-understood, we postulate that the VLCFA elevations reflect a systemic inflammatory response and secondary peroxisomal dysfunction that improves once maternal autoantibodies wane after birth. Additional evaluation of this phenomenon is warranted to better understand the intricate biochemical, clinical, and possible therapeutic overlap between autoimmunity, inflammation, peroxisomal dysfunction, and human disease.

Sex-specific newborn screening for X-linked adrenoleukodystrophy.

Males with X-linked adrenoleukodystrophy (ALD) are at high risk for developing adrenal insufficiency and/or progressive leukodystrophy (cerebral ALD) at an early age. Pathogenic variants in ABCD1 result in elevated levels of very long-chain fatty acids (VLCFA), including C26:0-lysophosphatidylcholine (C26:0-LPC). Newborn screening for ALD enables prospective monitoring and timely therapeutic intervention, thereby preventing irreversible damage and saving lives. The Dutch Health Council recommended to screen only male newborns for ALD without identifying untreatable conditions associated with elevated C26:0-LPC, like Zellweger spectrum disorders and single peroxisomal enzyme defects. Here, we present the results of the SCAN (Screening for ALD in the Netherlands) study which is the first sex-specific newborn screening program worldwide. Males with ALD are identified based on elevated C26:0-LPC levels, the presence of one X-chromosome and a variant in ABCD1, in heel prick dried bloodspots. Screening of 71 208 newborns resulted in the identification of four boys with ALD who, following referral to the pediatric neurologist and confirmation of the diagnosis, enrolled in a long-term follow-up program. The results of this pilot show the feasibility of employing a boys-only screening algorithm that identifies males with ALD without identifying untreatable conditions. This approach will be of interest to countries that are considering ALD newborn screening but are reluctant to identify girls with ALD because for girls there is no direct health benefit. We also analyzed whether gestational age, sex, birth weight and age at heel prick blood sampling affect C26:0-LPC concentrations and demonstrate that these covariates have a minimal effect.

In vivo gene editing via homology-independent targeted integration for adrenoleukodystrophy treatment.

Adrenoleukodystrophy (ALD) is caused by various pathogenic mutations in the X-linked ABCD1 gene, which lead to metabolically abnormal accumulations of very long-chain fatty acids in many organs. However, curative treatment of ALD has not yet been achieved. To treat ALD, we applied two different gene-editing strategies, base editing and homology-independent targeted integration (HITI), in ALD patient-derived fibroblasts. Next, we performed in vivo HITI-mediated gene editing using AAV9 vectors delivered via intravenous administration in the ALD model mice. We found that the ABCD1 mRNA level was significantly increased in HITI-treated mice, and the plasma levels of C24:0-LysoPC (lysophosphatidylcholine) and C26:0-LysoPC, sensitive diagnostic markers for ALD, were significantly reduced. These results suggest that HITI-mediated mutant gene rescue could be a promising therapeutic strategy for human ALD treatment.

The impacts of adrenoleukodystrophy newborn screening on the evaluation of adrenal dysfunction in male children: An integrative literature review.

PROBLEM: Adrenoleukodystrophy (ALD) is an x-linked genetic condition with a high risk of adrenal dysfunction recommended for newborn screening. This review aims to critically appraise and synthesize existing literature identifying the impacts of ALD newborn screening in the United States on the evaluation and treatment of adrenal dysfunction in male children. ELIGIBILITYCRITERIA: An integrative literature review was conducted using the Embase, PubMed, and CINAHL databases. English-language primary source studies published in the past decade and seminal studies were included. SAMPLE: Twenty primary sources met the inclusion criteria, including five seminal studies. RESULTS: Three major themes emerged from the review: 1) prevention of adrenal crisis, 2) unexpected outcomes, and 3) ethical impacts. CONCLUSIONS: ALD screening increases disease identification. Serial adrenal evaluation prevents adrenal crisis and death; data is needed to establish predictive outcomes in ALD prognosis. Disease incidence and prognosis will become more apparent as states increasingly add ALD screening to their newborn panel. IMPLICATIONS FOR PRACTICE: Clinicians need awareness of ALD newborn screening and state screening protocols. Families first learning of ALD through newborn screening results will require education, support, and timely referrals for appropriate care.

Detection of Characteristic Phosphatidylcholine Containing Very Long Chain Fatty Acids in Cerebrospinal Fluid from Patients with X-Linked Adrenoleukodystrophy.

X-linked Adrenoleukodystrophy (X-ALD) is a rare genetic neurological disorder caused by a mutation of the ABCD1 gene that encodes a peroxisomal ABC protein ABCD1. ABCD1 has a role in transporting very long chain fatty acid (VLCFA)-CoA into the peroxisome for ß-oxidation. ABCD1 dysfunction leads to reduced VLCFA ß-oxidation and in turn increased VLCFA levels in the plasma and the cells of all tissues; these increased plasma levels have been used to diagnose X-ALD. It has been reported that plasma VLCFA is not correlated with the severity and disease phenotype of X-ALD. Therefore, we cannot predict the disease progression by the plasma VLCFA level. Cerebrospinal fluid (CSF) is constantly produced by brain, and thus levels of lipids containing VLCFA in CSF might be informative in terms of assessing X-ALD pathology. LC-MS/MS-based analysis showed that phosphatidylcholine (PC) containing VLCFA signals, such as PC 40 : 0(24 : 0/16 : 0), PC 42 : 0(26 : 0/16 : 0), PC 44 : 4(24 : 0/20 : 4) and PC 46 : 4(26 : 0/20 : 4) were characteristically detected only in the CSF from patients with X- ALD. In the present study, we analyzed limited number of patient's CSF samples (2 patients with X-ALD) due to the limitations of the availability for CSF samples from this rare disease. However, our finding would offer helpful information for studying the disease progression biomarkers in X-ALD. To our knowledge, this is the first report of analyzing lipids containing VLCFA in CSF from patients with X-ALD.

Diagnosis, treatment and genetic analysis of a case of skin hyperpigmentation as the only manifestation with X-linked adrenoleukodystrophy.

X-linked adrenoleukodystrophy (X-ALD) is an inherited disease caused by a mutation in the adenosine 5'-triphosphate binding cassette subfamily D member 1 (ABCD1) gene encoding a peroxisomal transmembrane protein, which has various clinical manifestations and a rapid progression from initial symptoms to fatal inflammatory demyelination. Therefore, identification of early clinical symptoms and further early diagnosis as well as treatment can effectively prevent disease development. In this study, we reported the laboratory and radiographic features in a rare case of X-ALD with 3-year skin hyperpigmentation as the only manifestation. And the ABCD1 gene was sequenced for the patient and his parents by a high-throughput sequencing method. The results of laboratory examination showed adrenocortical hypofunction and increased serum concentrations of very long-chain fatty acids. Brain MRI showed no obvious abnormal signal shadow. A hemizygous mutation of c.521A>C was detected in the ABCD1 gene of the patient, and his mother has the same site heterozygous mutation. Therefore, this patient was diagnosed as "X-linked adrenoleukodystrophy". During the follow-up, adrenocortical hypothyroidism did not improve, and brain MRI showed few high-FLAIR signals in the white matter of the right radial corona and left parietal lobe, suggesting possible brain injury. X-ALD patients with only skin manifestations but no neurological abnormalities are easily neglected, but early diagnosis and early intervention are important ways to delay the progression of this disease. Therefore, genetic testing for early X-ALD is recommended in all male children patients with skin pigmentation as the sole clinical presentation and subsequent diagnosis of adrenal hypofunction.

MRI surveillance of boys with X-linked adrenoleukodystrophy identified by newborn screening: Meta-analysis and consensus guidelines.

BACKGROUND: Among boys with X-Linked adrenoleukodystrophy, a subset will develop childhood cerebral adrenoleukodystrophy (CCALD). CCALD is typically lethal without hematopoietic stem cell transplant before or soon after symptom onset. We sought to establish evidence-based guidelines detailing the neuroimaging surveillance of boys with neurologically asymptomatic adrenoleukodystrophy. METHODS: To establish the most frequent age and diagnostic neuroimaging modality for CCALD, we completed a meta-analysis of relevant studies published between January 1, 1970 and September 10, 2019. We used the consensus development conference method to incorporate the resulting data into guidelines to inform the timing and techniques for neuroimaging surveillance. Final guideline agreement was defined as >80% consensus. RESULTS: One hundred twenty-three studies met inclusion criteria yielding 1285 patients. The overall mean age of CCALD diagnosis is 7.91 years old. The median age of CCALD diagnosis calculated from individual patient data is 7.0 years old (IQR: 6.0-9.5, n = 349). Ninety percent of patients were diagnosed between 3 and 12. Conventional MRI was most frequently reported, comprised most often of T2-weighted and contrast-enhanced T1-weighted MRI. The expert panel achieved 95.7% consensus on the following surveillance parameters: (a) Obtain an MRI between 12 and 18 months old. (b) Obtain a second MRI 1 year after baseline. (c) Between 3 and 12 years old, obtain a contrast-enhanced MRI every 6 months. (d) After 12 years, obtain an annual MRI. CONCLUSION: Boys with adrenoleukodystrophy identified early in life should be monitored with serial brain MRIs during the period of highest risk for conversion to CCALD.

Targeted metabolomics revealed changes in phospholipids during the development of neuroinflammation in Abcd1tm1Kds mice and X-linked adrenoleukodystrophy patients.

X-linked adrenoleukodystrophy (X-ALD) is the most common leukodystrophy. Despite intensive research in recent years, it remains unclear, what drives the different clinical disease courses. Due to this missing pathophysiological link, therapy for the childhood cerebral disease course of X-ALD (CCALD) remains symptomatic; the allogenic hematopoietic stem cell transplantation or hematopoietic stem-cell gene therapy is an option for early disease stages. The inclusion of dried blood spot (DBS) C26:0-lysophosphatidylcholine to newborn screening in an increasing number of countries is leading to an increasing number of X-ALD patients diagnosed at risk for CCALD. Current follow-up in asymptomatic boys with X-ALD requires repetitive cerebral MRIs under sedation. A reliable and easily accessible biomarker that predicts CCALD would therefore be of great value. Here we report the application of targeted metabolomics by AbsoluteIDQ p180-Kit from Biocrates to search for suitable biomarkers in X-ALD. LysoPC a C20:3 and lysoPC a C20:4 were identified as metabolites that indicate neuroinflammation after induction of experimental autoimmune encephalitis in the serum of Abcd1tm1Kds mice. Analysis of serum from X-ALD patients also revealed different concentrations of these lipids at different disease stages. Further studies in a larger cohort of X-ALD patient sera are needed to prove the diagnostic value of these lipids for use as early biomarkers for neuroinflammation in CCALD patients.

Bilateral testicular masses and adrenal insufficiency: is congenital adrenal hyperplasia the only possible diagnosis? First two cases of TARTS described in Addison-only X-linked adrenoleukodystrophy and a brief review of literature.

BACKGROUND: Testicular adrenal rest tumors (TARTs) are benign masses deemed to originate from pluripotent testicular steroidogenic cells that grow under chronic ACTH stimulation. These lesions, occasionally misdiagnosed as Leydig cell tumors (LCTs), are typically described in patients with congenital adrenal hyperplasia (CAH). X-linked adrenoleukodystrophy (X-ALD) is an inherited disorder of beta-oxidation with accumulation of very long chain fatty acids (VLCFAs) in various tissues, and a rare cause of primary adrenal insufficiency (PAI). TARTs have never been associated with X-ALD. CASE 1 DESCRIPTION: A 19-year old male, who had previously undergone bilateral enucleation of presumed LCTs, was referred to our unit. Follow-up scans showed persistent bilateral lesions compatible with TARTs. Biochemical exams revealed PAI but excluded CAH. A serum VLCFAs panel was consistent with X-ALD, with gene testing confirming the diagnosis. Histological revision of the previously resected testicular lesions was compatible with TARTs. Start of glucocorticoid replacement therapy was associated with a reduction of testicular masses. CASE 2 DESCRIPTION: A 26-year old X-ALD male was diagnosed with bilateral testicular lesions compatible with TARTs. These lesions increased after ACTH elevation following switch to modified-release hydrocortisone. Clinical and sonographic findings allowed for a "watchful-waiting" approach, avoiding unnecessary surgery. CONCLUSION: These are the first cases reported of TARTs in patients with X-ALD-associated PAI. Testicular lesions in patients with an early onset of ACTH elevation, regardless of the cause, should always be thoughtfully investigated, as they may reveal themselves as TARTs. We suggest that all patients affected from chronic ACTH elevation of a young age of onset should undergo testicular ultrasound in order to evaluate the presence of these lesions. GRT in these patients might also help preserving fertility.

Geographic and Specialty Access Disparities in US Pediatric Leukodystrophy Diagnosis.

OBJECTIVE: To examine disparities in the diagnosis of leukodystrophies including geographic factors and access to specialty centers. STUDY DESIGN: Retrospective cohort study of pediatric patients admitted to Pediatric Health Information System hospitals. Patients with leukodystrophy were identified with International Classification of Diseases, Tenth Revision, Clinical Modification diagnostic codes for any of 4 leukodystrophies (X-linked adrenoleukodystrophy, Hurler disease, Krabbe disease, and metachromatic leukodystrophy). We used 3-level hierarchical generalized logistic modeling to predict diagnosis of a leukodystrophy based on distance traveled for hospital, neighborhood composition, urban/rural context, and access to specialty center. RESULTS: We identified 501 patients with leukodystrophy. Patients seen at a leukodystrophy center of excellence hospital were 1.73 times more likely to be diagnosed than patients at non-center of excellence hospitals. Patients who traveled farther were more likely to be diagnosed than those who traveled shorter. Patients living in a Health Professionals Shortage Area zip code were 0.86 times less likely to be diagnosed than those living in a non-Health Professionals Shortage Area zip code. CONCLUSIONS: Geographic factors affect the diagnosis of leukodystrophies in pediatric patients, particularly in regard to access to a center with expertise in leukodystrophies. Our findings suggest a need for improving access to pediatric specialists and possibly deploying specialists or diagnostic testing more broadly.

A 29-year-old patient with adrenoleukodystrophy presenting with Addison's disease.

Adrenoleukodystrophy (ALD) is an X-linked disorder caused by a hemizygous mutation of the ABCD1 gene. Patients with ALD show progressive central nervous system demyelination and primary adrenal insufficiency. In Japan, most reported ALD cases were childhood-onset, and only one case of an adult patient with Addison's disease form of ALD has ever been reported. Herein, we present a case of a 29-year-old man with Addison's disease form of ALD. The patient had anorexia, weight loss, and skin pigmentation from 18 years of age. At first visit, his weight had decreased by 12 kg from 57 kg when he was 15 years old. Endocrinological examination showed low serum cortisol (1.2 µg/dL) with high plasma ACTH (4,750 pg/mL), and abdominal computed tomography showed normal adrenal glands. Very-long-chain fatty acid (VLCFA) levels were elevated, and the ABCD1 mutation, p.Gly116Arg, was identified in hemizygous state. He had no significant neurological findings on physical examination and no white matter lesions on brain magnetic resonance imaging (MRI). He was diagnosed with ALD presenting as Addison's disease, and glucocorticoid replacement therapy was initiated. Four years after the diagnosis, he still did not show any neurological findings and any white matter lesions on brain MRI. Evaluating VLCFA levels for ALD diagnosis is important in young adult men with idiopathic primary adrenal insufficiency as well as in children. Early diagnosis enables more rational approaches including the early detection of neurological complications and might improve the prognosis of patients.

Integrative lipidomic and transcriptomic analysis of X-linked adrenoleukodystrophy reveals distinct lipidome signatures between adrenomyeloneuropathy and childhood cerebral adrenoleukodystrophy.

Precise pathophysiology with respect to the phenotypic variations and severity of X-ALD, specifically between adrenomyeloneuropathy (AMN) and childhood cerebral adrenoleukodystrophy (CCALD), has not been fully discovered. Herein, a systematic analysis using multi-layered lipidomics and transcriptomics was conducted to elucidate distinctive metabolic biosignatures among healthy control, AMN, and CCALD. Significant alterations regarding the accumulation of very long chain fatty acids were found in various lipid species such as phospholipids, glycerolipids, and sphingolipids. Remarkably, TG and CER that are physiologically essential were markedly down-regulated in CCALD than AMN. Transcriptomic analysis further supported the robustness of our findings by providing valuable information on the gene expressions of the regulatory factors. For instance, regulators of sphingolipid catabolism (SMPD1, CERK, and SPHK1) and TG anabolism (GPAM, GPAT2, and MBOAT2) were more up-regulated in AMN than in CCALD. These observations, among others, were in line with the recognized alterations of the associated lipidomes. In conclusion, the homeostatic imbalance of the complex lipid networks may be pathogenically important in X-ALD and the particular dysregulations of TG and CER may further influence the severity of CCALD among X-ALD patients.

Early Onset Primary Adrenal Insufficiency in Males with Adrenoleukodystrophy: Case Series and Literature Review.

The lifetime risk for adrenal insufficiency in male children with adrenoleukodystrophy (ALD) is estimated at 80%-86%. Prior to newborn screening, male children with ALD were identified by family history or after symptom development. These young patients with ALD and adrenal insufficiency support newborn screening for ALD.

Expanding the concept of peroxisomal diseases and efficient diagnostic system in Japan.

The concept of peroxisomal diseases is expanding because of improvements in diagnostic technology based on advanced biochemical analysis and development of next-generation sequencing. For quicker and more accurate diagnosis of as many patients as possible, we developed a new diagnostic system combining the conventional diagnostic system and comprehensive mutational analysis by whole-exome sequencing in Japan. Adrenoleukodystrophy (ALD) is the most common peroxisomal disease. In the cerebral type of ALD, hematopoietic stem cell transplantation is the only treatment in the early stage, and thus prompt diagnosis will improve the prognosis of affected patients. Furthermore, it is also important to identify pre-symptomatic patients by family analysis of probands by providing appropriate disease information and genetic counseling, which will also lead to early intervention. Here, we summarize current information related to peroxisomal diseases and ALD and introduce our efficient diagnostic system for use in Japan, which resulted in the diagnosis of 73 Japanese patients with peroxisome biogenesis disorders, 16 with impaired ß-oxidation of fatty acids, three with impaired etherphospholipid biosynthesis, and 191 Japanese families with ALD so far.

A report on state-wide implementation of newborn screening for X-linked Adrenoleukodystrophy.

Minnesota became the fourth state to begin newborn screening (NBS) for X-linked adrenoleukodystrophy (X-ALD) in 2017. As there is limited retrospective data available on NBS for X-ALD, we analyzed Minnesota's NBS results from the first year of screening. C26:0 lysophosphatidylcholine (C26:0-LPC) screening results of 67,836 infants and confirmatory testing (ABCD1 gene and serum VLCFA analysis) for screen positives were obtained. Fourteen infants (nine males, five females) screened positive for X-ALD and all were subsequently confirmed to have X-ALD, with zero false positives. The birth prevalence of X-ALD in screened infants was 1 in 4,845 and 1 in 3,878 males, more than five times previous reported incidences. Pedigrees of affected infants were analyzed, and 17 male (mean age of 17) and 24 female relatives were subsequently diagnosed with X-ALD. Phenotypes of these family members included self-reported mild neuropathy symptoms in two males and seven females, and childhood cerebral disease (ccALD) and adrenal insufficiency in one male. We observed fewer cases of ccALD and adrenal insufficiency than expected in male family members (5.9% of males for both) compared to previous observations. Together, these findings suggest that the spectrum of X-ALD may be broader than previously described and that milder cases may previously have been underrepresented. Other challenges included a high frequency of variants of uncertain significance in ABCD1 and an inability to predict phenotypic severity. We posit that thoughtful planning to address these novel challenges and coordination by dedicated specialists will be imperative for successful implementation of population-based screening for X-ALD.