Adrenocortical atrophy and diffuse cerebral sclerosis

Endocrine dysfunction in adrenoleukodystrophy

X-linked adrenoleukodystrophy (ALD) is a peroxisomal disorder caused by mutations in the ABCD1 gene and characterized by impaired very long-chain fatty acid beta-oxidation. Clinically, male patients develop adrenal failure and a progressive myelopathy in adulthood, although age of onset and rate of progression are highly variable. Additionally, 40% of male patients develop a leukodystrophy (cerebral ALD) before the age of 18 years. Women with ALD also develop a myelopathy but generally at a later age than men and with slower progression. Adrenal failure and leukodystrophy are exceedingly rare in women. Allogeneic hematopoietic cell transplantation (HCT), or more recently autologous HCT with ex vivo lentivirally transfected bone marrow, halts the leukodystrophy. Unfortunately, there is no curative treatment for the myelopathy. In the following chapter, the biochemistry, pathology, and clinical spectrum of ALD are discussed in detail.

X-linked adrenoleukodystrophy (X-ALD): clinical presentation and guidelines for diagnosis, follow-up and management

X-linked adrenoleukodystrophy (X-ALD) is the most common peroxisomal disorder. The disease is caused by mutations in the ABCD1 gene that encodes the peroxisomal membrane protein ALDP which is involved in the transmembrane transport of very long-chain fatty acids (VLCFA; ≥C22). A defect in ALDP results in elevated levels of VLCFA in plasma and tissues. The clinical spectrum in males with X-ALD ranges from isolated adrenocortical insufficiency and slowly progressive myelopathy to devastating cerebral demyelination. The majority of heterozygous females will develop symptoms by the age of 60 years. In individual patients the disease course remains unpredictable. This review focuses on the diagnosis and management of patients with X-ALD and provides a guideline for clinicians that encounter patients with this highly complex disorder.

Keratoconjunctivitis sicca associated with achalasia of the cardia, adrenocortical insufficiency, and lacrimal gland degeneration: Keratoconjunctivitis sicca secondary to lacrimal gland degeneration may parallel degenerative changes in esophageal and adrenocortical function

OBJECTIVE/DESIGN

This study aimed to examine and describe three siblings with alacrima, the eldest of whom had associated achalasia and adrenocortical insufficiency.

PARTICIPANTS

Three affected siblings and four age-matched control subjects participated. INTERVENTION/MAIN OUTCOME MEASURES: The three children underwent complete ophthalmologic examinations; computed tomographic scanning of brain, orbit, chest, and abdomen; and measurement of serum cortisol. All three were subjected to a short synacthen challenge. Lacrimal gland biopsies were performed on the two younger subjects, and specimens were studied by light and electron microscopy.

RESULTS

All three children showed virtually absent tear secretion as tested by the Schirmer test. The resulting keratopathy was most severe in the oldest child, who developed bilateral corneal melting. The two younger children showed interpalpebral corneal staining with rose bengal. All three children improved after punctal occlusion. Addison's disease was present in the oldest child. Computed tomographic scanning showed absent lacrimal and shrunken adrenal glands in association with achalasia of the cardia in the oldest child. The lacrimal glands were found to be reduced in size in the next eldest child. When evaluated by electron microscopy, the lacrimal gland biopsy specimens from the two younger children showed neuronal degeneration associated with depletion of secretory granules in the acinar cells.

CONCLUSION

In this disease, radiologic evidence of reducing lacrimal gland size with increasing age could represent a degenerative process. This may be paralleled by other signs and the possibility of adrenocortical insufficiency and achalasia of the cardia should be investigated in all children presenting with dry eyes. These children appear to have a progressive neuronal disease.

Adrenoleucodystrophy: neurophysiological aspects

Neurophysiological investigations (EEG, ERG, VEP) were carried out in 14 boys with adrenoleucodystrophy, and in two siblings with adrenocortical deficiency, but without neurological symptoms. Irregular large amplitude (200-800 microvolts) slow activity was found in the EEG of all adrenoleucodystrophy patients, usually more prominent over the posterior regions of the brain. No short duration spikes or complex wave were seen in any of the EEGs, even in those patients who had had seizures. Clinical deterioration was not always accompanied by an increase in EEG abnormalities. The ERG was of usual amplitude and wave form, while the VEP (flash) was altered in four cases. The two clinically unaffected siblings had normal ERG/VEP, and only a modest excess of slow waves in the EEG. The neurophysiological findings in adrenoleucodystrophy are not seen in other diseases with similar clinical symptoms in the same age group.

Biochemical study of adrenoleukodystrophy (ALD)

Adrenoleukodystrophy (ALD) is an x-linked hereditary neurological disorder characterized by the accumulation of cholesterol ester with long chain fatty acids in the brain and adrenal gland. We examined cholesterol ester metabolism for the postmortem brain tissues of ALD patients, using cholesterol ester with short and long chain fatty acids as the substrate for hydrolyzing enzyme, as well as short and long chain fatty acids for synthesizing enzyme. No enzyme abnormality was found. However, there was a discrepancy between hydrolytic and synthetic activities with short or long chain fatty acids. The findings suggest that the accumulation of cholesterol ester with long chain fatty acids in ALD brain is not due to enzyme abnormalities, but is a secondary phenomenon which comes from abnormal fatty acid metabolism causing a high concentration of long chain fatty acids.

EEG, pattern-evoked potentials and nerve conduction velocity in a family with adrenoleucodystrophy

In a family with 8 children one case of adrenoleucodystrophy (ALD), verified by autopsy, 2 cases with clinical signs of ALD and four other clinically healthy subjects with pathological ACTH tests were found. As an initial sign in the EEG, temporo-occipital slowing occurred. Further EEG studies showed spread of the primary local abnormalities, indicating diffuse brain dysfunction during progression of the disease. Terminal EEG flattening may be characteristic for late stages of the disease. No correlation could be established between lateralization, paroxysms and actual stage of the disease. Abnormal EEGs occurred not only in clinically and subclinically affected male patients, but also in a girl, who might be a carrier of ALD. Visual evoked potentials showed an increased latency of the P2 wave in the clinically, and in one subclinically, affected subjects. Motor nerve conduction velocity was reduced in only 2 patients. Antidromic sensory nerve conduction velocity of the median nerve was normal in all patients.

Familial glucocorticoid deficiency with achalasia of the cardia and deficient tear production

Isolated glucocorticoid failure associated with achalasia of the cardia is described in two pairs of siblings in separate families. Defective tear production is also present in three of the patients, and one shows other signs of autonomic dysfunction. Two other families with adrenal insufficiency and achalasia are known. This unusual association probably represents a familial disorder of as yet unknown aetiology.

Skin and conjunctival biopsies in adrenoleukodystrophy

Conjunctival and skin biopsies were performed in an 11 1/2 year-old caucasian male affected by adrenoleukodystrophy (ALD). In Schwann cells surrounding myelinated axons in conjunctival and dermal nerve bundles, empty clefts and few arrays of lamellae were discovered. The vacuolization in the eccrine glands of the skin, another striking feature, has not been reported previously in ALD. The obtained results suggest that ALD can be diagnosed in skin specimens precluding major surgery for biopsy. They provide support to the hypothesis of Schaumburg et al. (1975) that ALD is a generalized metabolic disorder.

Adrenoleukodystrophy (Siemerling-creutzfeldt disease): Heterozygote with two clonal fibroblast populations

On the fifth day after subcultivation,, fibroblasts of two unrelated patients with adrenoleukodystrophy (Siemerling-Creutzfeldt disease (SCD)) developed typical morphologic anomalies which could be seen by light microscopy. From skin biopsy material of an obligatorily heterozygous womam, both normal and morphologically defective colonies could be isolated. These findings suggest that the morphologic alterations are an expression of the defect in Siemerling-Creutzfeldt disease. Futhermore, they suggest that the SCD locus is subject to lyonization.

Neurochemical findings in adreno-leukodystrophy

The results of neurochemical examination of brain tissue derived from 2 cases of adreno-leukodystrophy have been presented. Both white and grey matter contained suadanophilic material. Although free fatty acid was also present, cholesteryl ester accounted for the bulk of the sudanophilic material. Total cholesterol, galactolipid and phospholipid content was reduced in both white and grey matter. The lipid loss was particularly severe from white matter indicative of considerable demyelination. Cholesterol was found to be the only major sterol present in white or grey matter. Subcellular fractionation of the diseased white matter resulted in myelin and two related fractions, one of which was very fatty and was rich in steryl ester. Morphological examination of myelin indicated loosely-packed lamellae. All of 3 fractions had adenosine 2',6'-cyclic nucleotide-3'-phosphohydrolase activity. Myein and the fraction not rich in cholesteryl ester had discernable basic protein bands when examined by polyacrylamide gel electrophoresis. Analysis of the fatty acid composition of choline and ethanolamine glycerophospholipids indicated a general increase of saturated fatty acids, relative to control values and a decrease in long-chain fatty acids. Examination of sphingomyelin fatty acids also demonstrated a loss of long-chain fatty acids. The fatty acid composition of the cholesteryl esters from white and grey matter differed. The findings indicate generalized damage to the brain, both of white and grey matter, with the damage to the white matter being much more severe. No abnormal sterol or other lipid was isolated.

Adrenoleukodystrophy with disease of the eye and optic nerve

Adrenoleukodystrophy is an X-chromosome-linked recessive disease characterized by primary atrophy of the adrenal glands with or without Addison's disease and low plasma cortisol levels, and a degeneration of white matter of the central nervous system with blindness. In suspected cases of adrenoleukodystrophy an impaired rise in plasma cortisol levels after adrenocorticotrophin stimulation may be diagnostic. With the electron microscope, pathognomonic intracytoplasmic lamellar inclusions have been seen in adrenal cortical cells, peripheral nerve Schwann's cells, testicular interstitial cells, and in macrophages of the brain. Adrenoleukodystrophy appears to be a genetically determined lipid storage disease with an error in membrane sterol metabolism. A 10-year-old boy with adrenoleukodystrophy had visual loss, a prominent early symptom. The ocular abnormality consisted of a disproportionate loss of nerve fibers from the macular region. No intracytoplasmic lamellar inclusions were identified in cells representing macrophages within the optic nerve. They contained myelin debris suggestive of end-stage disease.

Spastic paraplegia associated with Addison's disease: adult variant of adreno-leukodystrophy

Clinical and pathological features of an adult variant of adreno-leukodystrophy (ALD) are presented. A male with clinical and laboratory signs of Addison's disease (AD) developed at age 22 a slowly progressing paraplegia with slight sensory deficits in both legs and bladder and sphincter dysfunctions; he died at age 24 in an AD crisis. Autopsy revealed hyperplasia of lymphatic tissues, lymphocytic infiltrates in various organs including the CNS and adrenocortical atrophy with prominence of large ballooned, sometimes bizarre and occassionally striated cortical cells. CNS lesions consisted in incomplete demyelination of long tracts of brain stem and spinal cord with accentuation in the pyramical tracts; in these areas, perivascular cuffs of "epitheloid" histiocytic cells contained a strongly PAS-positive non-sudanophilic material. Electron microscopy demonstrated massive stroge of leaflet structures in perivascular histiocytes identical to the lamellar profiles previously described as specific for ALD. Some leaflets were found in close contact with compact lamellar arrays and with an electron-dense fingerprint material within astrocytes. In our case, the spastic paraplegia-AD syndrome which has been described previously in several clinical observations could be neuropathologically classified as an adult variant of ALD. Several differences to "classical" ALD occurring in young boys are stressed: the predominance of the endocrine disorder probably accounting for some of the perivascular lymphocyte infiltrates within the CNS; the absence of both clinical and pathological signs of diffuse cerebral involvement and the peculiar topistic pattern of CNS lesions and the very slow evolution of neurological signs paralleled by the absence of active sudanophilic demyelinating lesions. The possible mechanism of demyelination and the nature of the suggested metabolic defect in ALD are discussed. The ultrastructurally prominent leaflet structures may originate from myelin remnants, thus relating ALD to pathological storage of a myelin degradation product.

Adrenocortical insufficiency and diffuse cerebral sclerosis. Problems of presentation and diagnosis

Three cases of adrenocortical insufficiency with diffuse cerebral sclerosis are described. One, which was confirmed by brain biopsy, had a family history of the combined disorder affecting members of a previous generation; this has not been previously reported; however pathological confirmation of the diagnosis in the earlier cases was not available. Two cases presented as acute neurosurgical emergencies and attention is drawn to this mode of presentation. Problems of aetiology, presentation and diagnosis are discussed and the finding of normal basal steroid levels is stressed.

Adreno-leukodystrophy (sex-linked Schilder's disease). A pathogenetic hypothesis based on ultrastructural lesions in adrenal cortex, peripheral nerve and testis

Striated adrenal cells in the zona reticularis and inner fasciculata apparently constitute the initial adrenolytic lesion in patients with adreno-leukodystrophy (ALD). Cytoplasmic ballooning and macrovacuolization develop after the striations, and probably represent exaggerated responses to adrenocorticotropin (ACTH). Intracytoplasmic lamellae and lamellar-lipid profiles, containing a free 3beta-hydroxysterol, are the ultrastructural correlates of the striations seen with the light microscope. The ultrastructural demonstration of intracytoplasmic lamellae and lamellar-lipid profiles in adrenal striated cells, testicular interstitial cells, Schwann cells and brain macrophages from patients with ALD provides further morphologic evidence for a systemic metabolic defect common to the nervous and endocrine systems. In our experience, adrenal biopsy has proven to be the most effective procedure for the diagnosis of adreno-leukodystrophy. An hypothesis proposing a membrane abnormality affecting its stability and turnover might explain the concomitant destruction of adrenal cortex and brain in these patients.

Congenital adrenal hyperplasia. Report of a case with neurological complications

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Functional tests of adrenal axis in children with measurement of plasma cortisol by competitive protein binding

The competitive protein binding assay is the method of choice for estimation of plasma cortisol in children. Resting plasma cortisol levels in children without evidence of endocrine disease and with conditions affecting the hypothalamicpituitary-adrenal axis are reported. These showed wide variation, and stimulation tests are therefore essential for diagnosis. A normal response in the 30-minute tetracosactrin (Synacthen) test is defined as an increment of at least 10 μg/ml, with a final level of at least 25 μg/100 ml. 8 children with Addison's disease showed a minimal or negative response and 7 of 9 with hypopituitarism showed a subnormal response. Similar criteria, an increment of at least 10 μg/100 ml, with a final level of at least 25 μg/100 ml one hour after insulin, define a normal response to the intravenous insulin tolerance test. This test provides good discrimination between normal children and those with hypopituitarism, but negative results must be interpreted with caution.