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Query: UMLS:C0014848 (
achalasia
)
2,804
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Allgrove syndrome (isolated glucocorticoid deficiency,
achalasia
and alacrima) was found in eight members of an inbred French Canadian/North American Indian pedigree. The high degree of consanguinity supports an autosomal recessive mode of inheritance for this disorder. Six patients presented with hypoglycaemia and other evidence of cortisol deficiency between 2.5 and 8 years of age; however, two others became cortisol deficient after initial testing showed normal cortisol responses to ACTH, evidence that the glucocorticoid insufficiency of this syndrome may not be congenital, but may develop as late as the third decade. No evidence of mineralocorticoid deficiency has been found during 65 patient-years of follow-up. Alacrima was the earliest and most consistent clinical sign of Allgrove syndrome. Other manifestations of peripheral or autonomic neuropathy were found in four patients. The patients showed similar facial features, and three had significant velo-pharyngeal incompetence. All showed oesophageal dysmotility even in the absence of symptomatic dysphagia. In-vitro studies of lymphocyte ACTH binding showed no differences from normal controls. If such lymphocyte binding, as has been suggested, reflects adrenal
ACTH receptor
activity, these data would suggest that the glucocorticoid deficiency of Allgrove syndrome is not the result of a defect in that receptor. However, the observation that ACTH does not elicit increased adenylate cyclase activity even in normal lymphocytes casts considerable doubt on the physiological significance of ACTH binding to lymphocytes. It seems likely, therefore, that true ACTH receptors are not expressed on peripheral lymphocytes, and any conclusions regarding a possible receptor defect in Allgrove syndrome must await studies of receptor expression on adrenal cell membranes.
...
PMID:Allgrove syndrome: an autosomal recessive syndrome of ACTH insensitivity, achalasia and alacrima. 185 Jun 71
Isolated glucocorticoid deficiency (IGD) is an autosomal recessive disorder characterized by primary adrenocortical insufficiency, usually without mineralocorticoid deficiency. Occasionally, the disorder is associated with alacrima and
achalasia
of the esophagus (triple A syndrome), suggesting potential heterogeneity in its etiology. Mutations in the
ACTH receptor
gene have been reported in several families with IGD. We have amplified and directly sequenced the entire intronless
ACTH receptor
gene in 1 other family with IGD and 2 families with triple A syndrome. The proband with IGD was a homozygote for an A-->G substitution, changing tyrosine 254 to cysteine in the third extracellular loop of the receptor protein, probably interfering with ligand binding. Both of her parents were heterozygotes for this mutation, which was not detected in 100 normal alleles. No mutations were identified in the entire coding area of the
ACTH receptor
in the 2 families with triple A syndrome, supporting the idea of a developmental or postreceptor defect in this syndrome.
...
PMID:A novel mutation of the adrenocorticotropin receptor (ACTH-R) gene in a family with the syndrome of isolated glucocorticoid deficiency, but no ACTH-R abnormalities in two families with the triple A syndrome. 760 77
Hereditary primary adrenal insufficiency syndromes due to ACTH resistance include hereditary glucocorticoid deficiency (HGD) and Allgrove's syndrome (AS). Patients with both conditions present in childhood with failure to thrive, weakness, and fatigue or adrenal crisis; patients with AS in addition have alacrima and
achalasia
(triple A syndrome). We studied four kindreds with HGD and four kindreds with AS for abnormalities of the
ACTH receptor
(
ACTHR
) gene. The
ACTHR
coding sequence in all AS kindreds and two HGD kindreds was normal. Analysis of the
ACTHR
gene of the proband in one of the HGD kindreds showed him to be homozygous for the previously described G221T transition causing a Ser74Ile substitution of the protein, which has been shown to inactivate the
ACTHR
in signal transduction. The proband in another HGD kindred was found to be a compound heterozygote with the G221T transition in one allele and a novel C818A transition in the other allele of
ACTHR
. The C818A transition caused the substitution of the highly conserved Pro273 by His in the receptor protein. In vitro expression of the mutated
ACTHR
in mouse melanoma M3 cells showed that at a medium ACTH concentration of 3 nM, cells transfected with the wild-type
ACTHR
produced twofold and threefold, respectively, of the amount of intracellular cAMP when compared to cells transfected with the
ACTHR
carrying the Pro273His and the Ser74Ile mutation, respectively, confirming that HGD in this kindred is caused by loss-of-function mutations of the
ACTHR
. These results showed that the genetic cause of the ACTH-resistant syndromes is heterogeneous.
...
PMID:Genetic heterogeneity of adrenocorticotropin (ACTH) resistance syndromes: identification of a novel mutation of the ACTH receptor gene in hereditary glucocorticoid deficiency. 975 16
Inherited adrenocorticotropin (ACTH) insensitivity syndromes comprise a group of rare diseases in which resistance to ACTH is either the sole feature or associated with other symptoms. This review focuses on two autosomal recessive disorders, familial glucocorticoid deficiency (FGD) (MIM*202200) and the triple A syndrome (MIM*231550), which have at least three different molecular aetiologies. In FGD, several missense mutations within the coding region of the
ACTH receptor
(MC2-R) have been identified in some, but not all patients, and segregation analyses and functional studies in a Y6 cell expression system confirmed that these mutations cause the disease. Some cases of FGD are not linked to the MC2-R locus on chromosome 18p11.2 suggesting genetic heterogeneity. The triple A syndrome is clinically characterized by the triad of adrenal insufficiency,
achalasia
and alacrima and a variety of neurological symptoms. After excluding several candidate genes we mapped this syndrome to a 6 cM interval on chromosome 12q13 with no indication for genetic heterogeneity. The identification of the gene(s) causing FGD without mutations in the MC2-R and causing the triple A syndrome may reveal novel aspects in cell signalling and neuroendocrinology.
...
PMID:ACTH resistance syndromes. 1069 92
Familial isolated glucocorticoid deficiency is a form of potentially lethal hereditary unresponsiveness to ACTH that manifests as primary adrenal insufficiency, usually without mineralocorticoid deficiency. Affected children commonly present with hyperpigmentation, recurrent hypoglycemia, chronic asthenia and failure to thrive within the first 2 years of life. Typically, they have deficient production of cortisol and adrenal androgens in the presence of markedly elevated ACTH levels, while renin and aldosterone levels are usually normal and responsive to activation of the renin-angiotensin axis. Clinical awareness of these syndromes is of considerable prognostic and therapeutic importance. The etiological involvement of the
ACTH receptor
gene in isolated glucocorticoid deficiency has been recently established in many, but not all, affected families. Several naturally occurring mutations of the
ACTH receptor
gene have been identified to date and have helped illuminate the mechanisms of ligand binding and signal transduction by this receptor. Discovery of the molecular defect(s) responsible for isolated glucocorticoid deficiency in cases with a normal
ACTH receptor
gene coding region and for the triple A syndrome (adrenal insufficiency, alacrima,
achalasia
) will hopefully provide further insight into the mechanisms of adrenocortical function and will increase the prospect of new therapeutic approaches.
...
PMID:Isolated glucocorticoid deficiency and ACTH receptor mutations. 1071 60
ACTH resistance syndromes consist of a group of rare disorders with three various molecular etiologies. However, all these diseases share the feature of severe glucocorticoid adrenal insufficiency. The simplest disorder is the isolated familial glucocorticoid deficiency (FGD) which could be divided in two different types. In FGD type 1,
ACTH receptor
mutations have been described and are responsible for the loss of function of the receptor, leading to the ACTH unresponsiveness. Patients with FGD type 2 show the same phenotype as in the previous syndrome but no mutation of the
ACTH receptor
has been reported in these cases. It has been proposed that morbidity of one or several other gene(s) could be responsible for this syndrome although there is no information about their chromosomal localization. The third molecular form of the disease corresponds to the Triple A syndrome for the triad of association "ACTH resistance,
Achalasia
, Alacrima", thus reflecting a large spectrum of additional symptoms. It has recently been reported that the morbid gene in this last syndrome maps to chromosome 12q13. The aim of this review is to examine the clinical aspect as well as the current knowledge of the molecular and genetic aspects of the different forms of the disease.
...
PMID:[ACTH resistance syndromes]. 1108 94
ACTH insensitivity results from a group of rare autosomal recessive genetic defects. Familial glucocorticoid deficiency is one of these syndromes in which about half of all cases have inactivating mutations of the
ACTH receptor
. The remaining patients with this syndrome have defects in one or more other as yet unidentified genes that are unlinked to the
ACTH receptor
. The triple A syndrome is a distinct clinical syndrome which includes alacrima (absence of tears),
achalasia
and various neurological defects in addition to ACTH insensitivity. In all cases the defect lies in a gene located on chromosome 12.
...
PMID:The molecular pathogenesis of ACTH insensitivity syndromes. 1135 96
Familial glucocorticoid deficiency due to corticotropin (ACTH) resistance consists of two distinct genetic syndromes that are both inherited as autosomal recessive traits: isolated ACTH resistance (iACTHR), which may be caused by inactivating mutations of the
ACTH receptor
(the
MC2R
gene) or mutations in an as yet unknown gene(s), and Allgrove syndrome (AS). The latter is also known as triple-A syndrome (MIM 231550). In three large cohorts of AS kindreds, the disease has been mapped to chromosome 12; most recently, mutations in the AAAS gene on 12q13 were found in these AS families. AAAS codes for the WD-repeat containing ALADIN (for alacrima-
achalasia
-adrenal insufficiency-neurologic disorder) protein. We investigated families with iACTHR (n = 4) and AS (n = 6) and a Bedouin family with ACTHR and a known defect of the TSH receptor. Four AS families were of mixed extraction from Puerto Rico (PR); most of the remaining six families were Caucasian families from North America (NA). Sequencing analysis found no
MC2R
genetic defects in any of the kindreds. No iACTHR kindreds, but all of AS families, had AAAS mutations. The previously reported IVS14+1G-->A splice donor mutation was found in all PR families, apparently due to a founder effect; one NA kindred was heterozygous for this mutation. In the latter family, long-range PCR failed to identify a deletion or other rearrangements of the AAAS gene. No other heterozygote or transmitting parent had any phenotype that could be considered part of AS. The IVS14+1G-->A mutation results in a premature termination of the predicted protein; although it was present in all PR families (in the homozygote state in three of them), there was substantial clinical variation between them. One PR family also carried a novel splice donor mutation of the AAAS gene in exon 11, IVS11+1G-->A; the proband was a compound heterozygote. A novel point mutation, 43C-->A(Gln15Lys), in exon 1 of the AAAS gene was identified in the homozygote state in a Canadian AS kindred with a milder AS phenotype. The predicted amino acid substitution in this family is located in a sequence that may participate in the preservation of stability of ALADIN beta-strands, whereas the splicing mutation in exon 11 may interfere with the formation of WD repeats in this molecule. We conclude that 1) AAAS does not appear to be frequently mutated in families with iACTHR; 2) AAAS is mutated in AS families from PR (that had previously been mapped to 12q13) and NA; and, 3) there is significant clinical variability between patients with the same AAAS defect.
...
PMID:Spectrum of mutations of the AAAS gene in Allgrove syndrome: lack of mutations in six kindreds with isolated resistance to corticotropin. 1170 18
Familial glucocorticoid deficiency (FGD) is a rare autosomal recessive disorder, in 40% of patients caused by mutation in the
ACTH receptor
gene. In the remaining affected persons most probably mutation refers to regulatory region of
ACTH receptor
or other factors responsible for differentiation of the adrenal cortex. FGD is characterized by elevated ACTH and low serum morning cortisol level that does not respond to exogenous ACTH stimulation. Mineralocorticoid function remains unaffected. Clinical symptoms of FGD are due to glucocorticoid deficiency and are manifested in infancy or early childhood. Typically they include skin hyperpigmentation, failure to thrive, hypoglycaemia, which in some children may be lethal. Allgrove's syndrome, is considered to be a separate condition, characterized by glucocorticoid deficiency along with alacrimia,
achalasia
and neurological deficits. Treatment of FGD includes substitution of glucocorticoids with dose adjustment depending on the clinical state. Such treatment usually prevents from hypoglycaemia and provides normal growth and development of the patient.
...
PMID:[Familial glucocorticoid deficiency]. 1788 Aug 14
Human adrenal development is a complex and relatively poorly understood process. However, significant insight into some of the mechanisms regulating adrenal development and function is being obtained through the analysis of individuals and families with adrenal hypoplasia. Adrenal hypoplasia can occur: (1) secondary to defects in pituitary adrenocorticotropin (ACTH) synthesis, processing and release (secondary adrenal hypoplasia; e.g. HESX1, LHX4, SOX3, TPIT, pituitary POMC, PC1); (2) as part of several ACTH resistance syndromes (e.g.
MC2R
/ACTHR, MRAP, Alacrima,
Achalasia
, Addison disease), or as (3) a primary defect in the development of the adrenal gland itself (primary adrenal hypoplasia; e.g. DAX1/NR0B1 - dosage-sensitive sex reversal, adrenal hypoplasia congenita critical region on the X chromosome 1). Indeed, the X-linked form of primary adrenal hypoplasia due to deletions or mutations in the orphan nuclear receptor DAX1 occurs in around half of male infants presenting with a salt-losing adrenal crisis, where no obvious steroidogenic defect (e.g. 21-hydroxylase deficiency), metabolic abnormality (e.g. neonatal adrenoleukodystrophy) or physical cause (e.g. adrenal haemorrhage) is found. Establishing the underlying basis of adrenal failure can have important implications for investigating associated features, the likely long-term approach to treatment, and for counselling families about the risk of other children being affected.
...
PMID:Disorders of adrenal development. 1849 31
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