The importance of testing for adrenoleucodystrophy in males with idiopathic Addison's disease

A patient with X-linked adrenoleukodystrophy presenting with central precocious puberty: a case report

X-linked adrenoleukodystrophy (X-ALD) is a peroxisomal disorder caused by the variations in the ATP-binding cassette sub-family D member 1 (ABCD1) gene. This study is the first to report central precocious puberty (CPP) in individuals with X-ALD. A 6-year-old boy exhibited mucocutaneous pigmentation, increased plasma adrenocorticotropic hormone levels, and elevated very long-chain fatty acids (VLCFA). We identified a variant, c.1826A>G (p. Glu609Gly), in exon 8 of the ABCD1 gene in the proband. Additionally, he displayed rapid growth, testicular volume of 5-6 mL, the onset of pubic hair, and pubertal levels of luteinizing hormone (LH), all meeting the diagnostic criteria for CPP.

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.

Adrenoleukodystrophy in the Differential Diagnosis of Boys Presenting with Primary Adrenal Insufficiency without Adrenal Antibodies

Adrenoleukodystrophy (ALD) is an X-linked, metabolic disorder caused by deficiency of peroxisomal ALD protein resulting in accumulation of very-long chain fatty acids (VLCFA), primarily in the adrenal cortex and central nervous system. Approximately 35-40% of boys with ALD develop cerebral ALD (CALD), which causes rapidly progressive cerebral demyelination, loss of neurologic function, and death. Approximately 70-80% of boys with ALD have impaired adrenal function prior to the onset of neurologic symptoms. We present a boy who had recurrent episodes of hypoglycaemia from age two years and was diagnosed with adrenal insufficiency without adrenal antibodies at age 5.5 years. Following initial normal VLCFA levels, subsequent VLCFA analysis demonstrated elevated C26 fatty acids consistent with peroxisomal dysfunction and suggestive of ALD, which was confirmed via molecular genetic analysis of the ABCD1 gene. Brain imaging at age 7 suggested cerebral involvement and the child underwent successful allogeneic hematopoietic stem cell transplantation. At last assessment (11.5 years old), he was performing as expected for age. This case highlights the importance of pursuing a diagnosis when clinical suspicion remains, and the significance of VLCFA analysis for patients with adrenal insufficiency without adrenal antibodies in securing an ALD diagnosis. Subsequent brain imaging surveillance can detect early, pre-symptomatic cerebral disease, allowing for timely treatment and successful arrest of cerebral disease progression.

Defining diagnostic cutoffs in neurological patients for serum very long chain fatty acids (VLCFA) in genetically confirmed X-Adrenoleukodystrophy

X-linked Adrenoleukodystrophy (X-ALD) is caused by mutations in the ABCD1 gene resulting in the accumulation of very long chain fatty acids (VLCFA). X-ALD is the most common peroxisomal disorder with adult patients (male and female) presenting with progressive spastic paraparesis with bladder disturbance, sensory ataxia with impaired vibration sense, and leg pain. 80% of male X-ALD patients have an adrenal failure, while adrenal dysfunction is rare in women with X-ALD. The objective of this study was to define optimal serum VLCFA cutoff values in patients with X-ALD-like phenotypes for the differentiation of genetically confirmed X-ALD and Non-X-ALD individuals. Three groups were included into this study: a) X-ALD cases with confirmed ABCD1 mutations (n = 34) and two Non-X-ALD cohorts: b) Patients with abnormal serum VCLFA levels despite negative testing for ABCD1 mutations (n = 15) resulting from a total of 1,953 VLCFA tests c) Phenotypically matching patients as Non-X-ALD controls (n = 104). Receiver operating curve analysis was used to optimize VLCFA cutoff values, which differentiate patients with genetically confirmed X-ALD and Non-X-ALD individuals. The serum concentration of C26:0 was superior to C24:0 for the detection of X-ALD. The best differentiation of Non-X-ALD and X-ALD individuals was obtained with a cutoff value of < 1.0 for the C24:0/C22:0 ratio resulting in a sensitivity of 97%, a specificity of 94.1% and a positive predictive value (PPV) of 83.8% for true X-ALD. Our findings further suggested a cutoff of < 0.02 for the ratio C26:0/C22:0 leading to a sensitivity of 90.9%, a specificity of 95.0%, and a PPV of 80.6%. Pearson correlation indicated a significant positive association between total blood cholesterol and VLCFA values. Usage of serum VLCFA are economical and established biomarkers suitable for the guidance of genetic testing matching the X-ALD phenotype. We suggest using our new optimized cutoff values, especially the two ratios (C24:0/C22:0 and C26:0/C22:0), in combination with standard lipid profiles.

Screening for X-linked adrenoleukodystrophy among adult men with Addison's disease

OBJECTIVES

X-linked adrenoleukodystrophy is an important cause of Addison's disease in boys, but less is known about its contribution to Addison's disease in adult men. After surveying all known cases of X-linked adrenoleukodystrophy in Norway in a separate study, we aimed to look for any missed cases among the population of adult men with nonautoimmune Addison's disease.

STUDY DESIGN

Among 153 adult men identified in a National Registry for Addison's Disease (75% of identified male cases of Addison's disease in Norway), those with negative indices for 21-hydroxylase autoantibodies were selected. Additionally, cases with low autoantibody indices (48-200) were selected. Sera from subjects included were analysed for levels of very long-chain fatty acids, which are diagnostic for X-linked adrenoleukodystrophy in men.

RESULTS

Eighteen subjects had negative indices and 17 had low indices for 21-hydroxylase autoantibodies. None of those with low indices and only one of those with negative indices were found to have X-linked adrenoleukodystrophy; this subject had already been diagnosed because of the neurological symptoms. Cases of Addison's disease proved to be caused by X-linked adrenoleukodystrophy constitute 1·5% of all adult male cases in Norway; the proportion among nonautoimmune cases was 15%.

CONCLUSIONS

We found X-linked adrenoleukodystrophy to be an uncommon cause of Addison's disease in adult men. However, this aetiological diagnosis has far-reaching consequences both for the patient and for his extended family. We therefore recommend that all adult men with nonautoimmune Addison's disease be analysed for levels of very long-chain fatty acids.

Atypical presentation of neuropsychiatric lupus with acanthosis nigricans

Cutaneous manifestations are commonly observed in pediatric patients with systemic lupus erythematosus. Acanthosis nigricans, however, is rarely reported, and even less often in association with neuropsychiatric manifestations of lupus erythematosus. We describe a 9-year-old boy with acute behavioral and cognitive deterioration, combined with cutaneous, diffuse hyperpigmented and hyperkeratotic plaques. Cerebral magnetic resonance imaging revealed cortical atrophy and white matter abnormalities involving the fornix, corpus callosum, and parieto-occipital periventricular regions. The presence of progressive cognitive and behavioral deterioration, combined with abnormal white matter signals on magnetic resonance imaging, led us to suspect X-linked adrenoleukodystrophy. The subsequent development of systemic signs, together with positive serologic tests, confirmed the diagnosis of neuropsychiatric lupus with acanthosis nigricans. We review the literature on acanthosis nigricans in systemic lupus erythematosus and the value of magnetic resonance imaging in evaluating patients with neuropsychiatric systemic lupus.

Adrenoleukodystrophy: a forgotten diagnosis in children with primary Addison's disease

The X linked adrenoleukodystrophy (X-ALD) is a peroxisomal disease caused by defects of the ABCD1 gene on chromosome Xq28 leading to accumulation of very long chain fatty acids (VLCFA), progressive demyelination and adrenal insufficiency. An 8-year-old boy was referred to our paediatric endocrinology clinic due to fatigue and hyperpigmentation with onset at 2-years old. Blood tests revealed mineralocorticoid insufficiency. Serum adrenocorticotropic hormone and cortisol concentrations were compatible with adrenal insufficiency. Adrenal antibodies were negative. The elevated plasmatic concentration of VLCFA and the genotype analysis with sequencing of ABCD1 gene established the diagnosis of X-ALD. Brain MRI showed demyelination of white matter in the peritrigonal regions. Steroid replacement was started with good response. He initiated restriction of VLCFA by reducing the intake of fatty foods. The authors highlight the importance of suspecting of X-ALD in the aetiology of primary adrenal insufficiency as the first sign of the disease.

Combined extraction of acyl carnitines and 26:0 lysophosphatidylcholine from dried blood spots: prospective newborn screening for X-linked adrenoleukodystrophy

X-linked adrenoleukodystrophy (X-ALD) is a severe genetic disorder that affects the nervous system, and the adrenal cortex. Newborn screening for X-ALD has been proposed to allow improved diagnosis along with prospective monitoring and treatment for this severe disorder. Newborn dried whole blood spot (DBS) 26:0 lysophosphatidyl choline was validated as a diagnostic marker for X-ALD and other peroxisomal disorders of peroxisomal β-oxidation. In this study, we developed a new one step extraction procedure that simultaneously extracts acyl carnitines and the lysophosphatidyl cholines from DBS. Further analysis of these metabolites has been performed by two different high throughput LC-MS/MS methods. The 26:0 lysophosphatidyl choline levels in this study were consistent with previously published values and discriminate between healthy and abnormal profiles. There is a very minor modification to the original acyl carnitine extraction procedure and our data indicates that there is no significant effect on acyl carnitine levels in DBS. Our new method potentially can be complementary to the current newborn screening panel. It successfully combines the existing method for acyl carnitine analysis and 26:0 lysophosphatidyl choline that can be applied for prospective X-ALD newborn screening.

Early diagnosis of cerebral X-linked adrenoleukodystrophy in boys with Addison's disease improves survival and neurological outcomes

Approximately one third of boys with X-linked adrenoleukodystophy (X-ALD) develop an acute, progressive inflammatory process of the central nervous system, resulting in rapid neurologic deterioration and death. Hematopoietic cell transplantation (HCT) can halt the progression of neurologic disease if performed early in the course of the cerebral form of X-ALD. We describe a retrospective cohort study of 90 boys with X-ALD evaluated at our institution between 2000 and 2009, to determine if early diagnosis of X-ALD following the diagnosis of unexplained adrenal insufficiency (AI) improves outcomes. We describe seven cases with a delay in the diagnosis of X-ALD and compare their outcomes to ten controls with the diagnosis of ALD made within 12 months following diagnosis of AI. At the time of evaluation for HCT, boys with a delay in the diagnosis of X-ALD had more extensive cerebral involvement and more limited functioning. These boys also were 3.9 times more likely to die and had significant advancement of cerebral disease after HCT, compared with boys with a timely diagnosis of X-ALD. In conclusion, the early diagnosis of cerebral X-ALD following the diagnosis of unexplained AI, and subsequent treatment with HCT improves both neurological outcomes and survival in boys with cerebral X-ALD.

Clinical aspects and adrenal functions in eleven Japanese children with X-linked adrenoleukodystrophy

X-linked adrenoleukodystrophy (X-ALD) is a genetic disease associated with demyelination of the central nervous system, adrenocortical insufficiency and accumulation of very long chain fatty acids. It is a clinically heterogeneous disorder ranging from a severe childhood cerebral form to an asymptomatic form. The incidence in Japan is estimated to be between 1:30,000 and 1:50,000 boys as determined by a nationwide retrospective survey between 1990 and 1999, which found no cases with Addison's form. We reviewed the medical records of eleven Japanese boys with X-ALD from 1990 to 2010 in our institute. Eight patients were detected by neuropsychological abnormalities, whereas a higher prevalence of unrecognized adrenocortical insufficiency (5/11: 45%) was observed than previously recognized. While no neurological abnormalities were demonstrated in two brothers, the elder brother had moderate Addison's disease at diagnosis and the presymptomatic younger brother progressed to Addison's disease six months after the diagnosis of X-ALD. Early detection of impaired adrenal function as well as early identification of neurologically presymptomatic patients by genetic analysis is essential for better prognosis. Addison's form might be overlooked in Japan; therefore, X-ALD should be suspected in patients with adrenocortical insufficiency.

Clinical profile of adrenoleukodysrophy

X-linked Adrenoleukodystrophy (ALD) is the most common of the peroxisomal disorder and is associated with functional defect of the very long chain fatty acid (VLCFA) oxidation leading to the accumulation of VLCFA in the white matter and adrenal cortex. Retrospective evaluation of medical records of ALD patients were carried out. In all the 5 patients the duration of the symptoms varied from 1-7 years. Most of them presented with Addisonian crisis (4/5) and hyperpigmentation (5/5), white half of them (3/5) had neurological symptoms. All patients had biochemical evidence of the adrenal insufficiency. All siblings of patients should be screened for the possibility of ALD with VLCFA.

[Primary adrenal insufficiency as the form of onset of adrenoleukodystrophy in a 4-year-old boy]

X-linked adrenoleukodystrophy is an inherited metabolic disease caused by the accumulation of saturated very long chain fatty acids (VLCFA). Given that the form of presentation can be primary adrenal insufficiency, diagnosis in affected males is important. Patient was a 4-year-old boy with attention deficit hyperactivity disorder, cutaneous-mucosal hyperpigmentation, and dehydration with hyponatremia and hyperpotassemia was diagnosed with adrenoleukodystrophy presenting as primary adrenal insufficiency. Antiadrenal antibodies: negative. Plasma VLCFA: C(26:0)=1.25mg/ml (0.18-0.48), C(24:0)/C(22:0) =1.53 (< 1), and C(26:0)/ C(22:0)=0.04 (< 0.02). Abdominal computed tomography: small adrenal glands. Cranial magnetic resonance imaging and evoked potentials: normal at diagnosis and with signs of white matter demyelination after 2 years of follow-up. Testing for an autoimmune etiology and adrenoleukodystrophy is important in boys with primary adrenal insufficiency before Addison's disease is diagnosed.

[Primary adrenal insufficiency in adults: 150 years after Addison]

Thomas Addison first described, 150 years ago, a clinical syndrome characterized by salt-wasting and skin hyperpigmentation, associated with a destruction of the adrenal gland. Even today, over a century after Addison's report, primary adrenal insufficiency can present as a life-threatening condition, since it frequently goes unrecognized in its early stages. In the 1850s, tuberculous adrenalitis was present in the majority of patients, but nowadays, autoimmune Addison's disease is the most common cause of primary adrenal insufficiency. In the present report, we show the prevalence of different etiologies, clinical manifestations and laboratorial findings, including the adrenal cortex autoantibody, and 21-hydroxylase antibody in a Brazilian series of patients with primary adrenal insufficiency followed at Divisão de Endocrinologia da Universidade Federal de São Paulo (UNIFESP) and at Faculdade de Medicina de Ribeirão Preto-USP (FMRP-USP).

Hematopoietic cell transplantation for inherited metabolic diseases: an overview of outcomes and practice guidelines

For the past two decades, hematopoietic cell transplantation (HCT) has been used as effective therapy for selected inherited metabolic diseases (IMD) including Hurler (MPS IH) and Maroteaux-Lamy (MPS VI) syndromes, childhood-onset cerebral X-linked adrenoleukodystrophy (X-ALD), globoid-cell leukodystrophy (GLD), metachromatic leukodystrophy (MLD), alpha-mannosidosis, osteopetrosis, and others. Careful pre-HCT evaluation is critical and coordinated, multidisciplinary follow-up is essential in this field of transplantation. The primary goals of HCT for these disorders have been to promote long-term survival with donor-derived engraftment and to optimize the quality of life. Guidelines for HCT and monitoring are provided; a brief overview of long-term results is also presented.

Insuficiência Adrenal Primária de Causa Genética

A insuficiência adrenal primária pode resultar em uma situação de risco de vida, quando não tratada ou quando o paciente é submetido a situações de estresse. Desta maneira, o reconhecimento, diagnóstico e tratamento correto e precoce da insuficiência adrenal é de fundamental importância na prática clínica. Por outro lado, o avanço no conhecimento dos mecanismos moleculares das diferentes causas genéticas de insuficiência adrenal tem permitido melhor entendimento não só da fisiopatologia, mas também do desenvolvimento e fisiologia da glândula adrenal. Esta revisão apresenta aspectos clínicos e moleculares de diferentes causas de insuficiência adrenal de origem genética.