Ophthalmic manifestations of Allgrove syndrome: report of a case

The Retina in Patients With Triple A Syndrome: A Window Into Neurodegeneration?

OBJECTIVE

Experimental evidence suggests that the clinical manifestations of Triple A syndrome result from oxidative stress. Several conditions caused by oxidative stress display retinal involvement. Our objective was to assess the retina and optic nerve involvement in children with Triple A syndrome.

METHODS

Eleven patients with genetically proven Triple A syndrome followed-up in our centre were approached for study participation. The main outcome was the measurement of the thicknesses of the different retinal layers by Optical Coherence Tomography (OCT).

RESULTS

9 patients with triple A syndrome had OCT measurements. 7 patients were children and 2 were adults; 4 were females and 5 were males. The 7 paediatric patients had at least two OCT measured at a mean interval of 7.9 months after the first one. The average Retinal Nerve Fibre Layer thickness was 74 ± 10 µm in patients compared to the paediatric reference range of 100 ± 2 µm (p<0.05).

CONCLUSIONS AND RELEVANCE

This is the first study to document retinal layer thicknesses in a series of patients with Triple A syndrome. Nearly all retinal thickness and peripapillary RNFL measurements were very significantly inferior to the reference range in Triple A patients, whatever their age. RNFL thinning was more marked at the temporal part of the optic nerve. OCT being non-invasive, it represents a promising tool to assess the severity of neurodegeneration in patients with Triple A syndrome.

A broad range of symptoms in allgrove syndrome: single center experience in Southeast Anatolia

BACKGROUND

Allgrove syndrome (OMIM 231550) is a rare autosomal recessive disease characterized by non-CAH primary adrenal insufficiency (non-CAH PAI), alacrima, and achalasia. It is caused by mutations in the AAAS gene. The syndrome is also associated with variable progressive neurological impairment and dermatological abnormalities.

METHODS AND RESULTS

We diagnosed 23 patients from 14 families with Allgrove syndrome, based on the presence of at least two characteristic symptoms, usually adrenal insufficiency and alacrima, between 2008 and 2018. A previously described nonsense variant of AAAS was detected in 19 patients from 12 families at homozygous state. Another novel homozygous mutation (c.394-397delCTGT) in AAAS was detected in four patients from two families. Presenting symptoms were alacrima (23/23; 100%), adrenal insufficiency (18/23; 78%), achalasia (13/23; 57%), short stature/growth retardation (16/23; 70%), hyperreflexia (15/23; 65%), palmoplantar hyperkeratosis (13/23; 57%), hyperpigmentation of the skin (10/23; 43%), hypoglycemia-induced convulsion (7/23; 30%), swallowing difficulty and vomiting (6/23; 26%). Serum DHEAS concentrations were low in all patients (23/23; 100%).

CONCLUSIONS

Clinical symptoms vary even among patients carrying the same mutation. Triple A syndrome should be considered in the etiology of non-CAH PAI in Arab populations and in Southeast Turkey. Any child with non-CAH PAI should be evaluated for the presence of alacrima and/or achalasia or family history of alacrima and/or achalasia. Children with alacrima and/or achalasia should also be investigated for adrenal insufficiency. Definitive molecular diagnosis is essential for early diagnosis and management of adrenal insufficiency, neurological symptoms, and growth retardation in patients and early diagnosis of as yet asymptomatic cases in the family, together with genetic counseling.

Inherited Paediatric Motor Neuron Disorders: Beyond Spinal Muscular Atrophy

Paediatric motor neuron diseases encompass a group of neurodegenerative diseases characterised by the onset of muscle weakness and atrophy before the age of 18 years, attributable to motor neuron loss across various neuronal networks in the brain and spinal cord. While the genetic underpinnings are diverse, advances in next generation sequencing have transformed diagnostic paradigms. This has reinforced the clinical phenotyping and molecular genetic expertise required to navigate the complexities of such diagnoses. In turn, improved genetic technology and subsequent gene identification have enabled further insights into the mechanisms of motor neuron degeneration and how these diseases form part of a neurodegenerative disorder spectrum. Common pathophysiologies include abnormalities in axonal architecture and function, RNA processing, and protein quality control. This review incorporates an overview of the clinical manifestations, genetics, and pathophysiology of inherited paediatric motor neuron disorders beyond classic SMN1-related spinal muscular atrophy and describes recent advances in next generation sequencing and its clinical application. Specific disease-modifying treatment is becoming a clinical reality in some disorders of the motor neuron highlighting the importance of a timely and specific diagnosis.

4A syndrome: ocular surface investigation in an Italian young patient

Background

Allgrove’s 4A syndrome determines ocular surface changes. This is the first report providing an up-to-dated analysis of the ocular surface in an affected patient.

Case presentation

An 18-years-old male Caucasian patient, with a complex progressive gait disorder and adrenal insufficiency, was referred for ophthalmic evaluation, as part of the clinical assessment. He underwent the following tests: best corrected visual acuity, tear osmolarity, tear film break-up time (BUT), corneal fluorescein staining, Schirmer’s I test, lid margin assessment, corneal sensitivity, in vivo corneal confocal microscopy, conjunctival impression cytology, tonometry and fundus exam. A dry eye condition was documented by the Schirmer’s I test of 0 mm/5’ in both eyes, accompanied by tear hyperosmolarity, mild meibomian gland dysfunction, reduced BUT, mucus filaments in the tear film and conjunctival epithelium metaplasic changes. The corneal confocal microscopy showed the presence of activated keratocytes, while the nerve pattern was normal.

Conclusions

The dry eye in this patient appears to be due to tear aqueous deficiency and can be considered as part of the 4A syndrome. The decreased tear production, resulting from a deterioration of the autonomic innervation of the lacrimal glands rather than an impaired corneal innervation, can be considered as part of the systemic autonomic dysfunction present in this disease.

Longitudinal neuropsychological profile in a patient with triple a syndrome

Triple A syndrome is an autosomal recessive disorder characterized by the triad of adrenocorticotropic hormone resistant adrenal insufficiency, achalasia, and alacrima. Our aim was to describe the neuropsychological characteristics and the cooccurring psychopathological and neurological disorders in an Italian male child suffering from Triple A syndrome at the time of admission (T0) and after one year of follow-up (T1). Many difficulties were observed in the motor domain, as well as in manual dexterity and static/dynamic balance domains of the motor task over time. In sharp contrast with previous literature reports on frequent mild cognitive dysfunction in patients with Triple A syndrome, our child did not show any mental retardation. By contrast, he showed an average IQ at T0 with a slight improvement at T1. To our knowledge, this report is the first describing neuropsychological profile and co-occurring psychopathological problems in a child with Triple A syndrome. Considering that the Triple A syndrome is a progressive disorder which can take years to develop the full-blown clinical picture, these patients require periodical medical controls. Moreover, assessment of neuropsychological and psychopathological features should be performed in patients with this disease, in order to underline the variability of this syndrome.

New ophthalmic features in a family with triple A syndrome

We report three subjects of a Greek family affected by triple A syndrome (AAAS). All patients underwent complete ophthalmic examination, full-field electroretinogram (ERG), visual evoked responses (VER), optical coherence tomography (OCT) and molecular analysis of the AAA gene. All patients had alacrima. In two of them, the proband and her brother, bilateral optic atrophy was assessed and the VER were pathological. In contrast, the ERG was normal. OCT showed a decrease of the retinal nerve fiber layer. The third case had only alacrima and the optic nerves were normal. The molecular genetic study of the AAAS gene revealed a homozygous missense mutation p.Ala167Val. To our knowledge this is the first time a family with AAAS has been investigated using OCT, VER and ERG. Our findings illustrate that the retina is not involved. There is also an interfamilial variability concerning the involvement of the optic nerves.

Case report of adult-onset Allgrove syndrome

Allgrove syndrome is a rare autosomal recessive disorder characterised by childhood onset, alacrima, oesophageal achalasia, adrenocortical insufficiency, neurological and occasionally autonomic involvement. Although the disease has been associated with mutations in the ALADIN gene on chromosome 12q13, it is genetically heterogeneous. The case we report is interesting because of its onset in adulthood, long duration of disease and prominent neurological dysfunctions. After the onset of neurological abnormalities the diagnosis went unrecognised for years until the patient presented for evaluation of dysphagia. The presence of achalasia with dysphagia, adrenal insufficiency, reduced tear production, optic atrophy and peripheral motor-sensory neuropathy with axonal loss led us to clinically diagnose Allgrove syndrome even though a genetic study showed no mutations in the ALADIN gene exons. The case we report shares many clinical features with Allgrove syndrome and, even with the limitations of a single case, underlines the variability in this syndrome and the need for appropriate investigations along with a multidisciplinary approach.

Pediatric autonomic disorders

The scope of pediatric autonomic disorders is not well recognized. The goal of this review is to increase awareness of the expanding spectrum of pediatric autonomic disorders by providing an overview of the autonomic nervous system, including the roles of its various components and its pervasive influence, as well as its intimate relationship with sensory function. To illustrate further the breadth and complexities of autonomic dysfunction, some pediatric disorders are described, concentrating on those that present at birth or appear in early childhood.

Genotypic heterogeneity and clinical phenotype in triple A syndrome: a review of the NIH experience 2000-2005

Triple A syndrome (AAAS, OMIM#231550) is an autosomal recessive condition characterized by adrenal insufficiency, achalasia, alacrima, neurodegeneration and autonomic dysfunction. Mutations in the AAAS gene on chromosome 12q13 have been reported in several subjects with AAAS. Over the last 5 years, we have evaluated six subjects with the clinical diagnosis of AAAS. Three subjects had mutations in the AAAS gene-- including one novel mutation (IVS8+1 G>A)-- and a broad spectrum of clinical presentations. However, three subjects with classic AAAS did not have mutations in the AAAS gene on both alleles. This finding supports the notion of genetic heterogeneity for this disorder, although other genetic mechanisms cannot be excluded.

Triple-A syndrome with prominent ophthalmic features and a novel mutation in the AAAS gene: a case report

Background

Triple-A syndrome (Allgrove syndrome) is an autosomal recessive disorder characterized by adrenal insufficiency, alacrima, achalasia, and – occasionally – autonomic instability. Mutations have been found in the AAAS gene on 12q13.

Case presentation

We present the case of a 12 year-old boy with classic systemic features of triple-A syndrome and several prominent ophthalmic features, including: accommodative spasm, dry eye, superficial punctate keratopathy, and pupillary hypersensitivity to dilute pilocarpine. MRI showed small lacrimal glands bilaterally. DNA sequencing of PCR-amplified fragments from the 16 exons of the AAAS gene revealed compound heterozygosity for a new, out-of-frame 5-bp deletion in exon 15, c1368-1372delGCTCA, and a previously-described nonsense mutation in exon 9, c938C>T, R286X.

Conclusions

In addition to known ophthalmic manifestations, triple-A syndrome can present with accommodative dysregulation and ocular signs of autonomic dysfunction.

New insights into the molecular basis of the triple A syndrome

The triple A syndrome (MIM*231550) is a rare autosomal recessive disorder characterized by adrenocorticotropic hormone (ACTH) resistant adrenal failure, achalasia, alacrima and a variety of neurological and dermatological features. Adrenal insufficiency usually presents in the first decade of life, however in some patients it may occur later in life or may even lack completely. Recently, we and others identified a novel gene on chromosome 12q13, designated AAAS (Achalasia-Addisonianism-Alacrima-Syndrome gene) which is mutated in patients with triple A syndrome. We investigated n=84 families including 111 patients with clinically suggested triple A syndrome and identified homozygous or compound heterozygous AAAS mutations in 78 families. Genotype/phenotype analyses revealed a highly variable occurrence, age of onset and severity of all clinical symptoms between patients with the same AAAS mutation. The obvious lack of a genotype/phenotype relationship is suggestive of modifying genes/factors which need to be determined. The AAAS protein function is unknown. With four WD repeats it belongs to the family of WD repeat-containing proteins which may exhibit a high degree of functional diversity. The subcellular localization of the protein and the determination of its putative binding partners will shed light on the role of the AAAS protein for the development and function of the adrenal gland and other neuroendocrine structures.