Oro-dental self-mutilation in familial dysautonomia

Elp1 function in placode-derived neurons is critical for proper trigeminal ganglion development

Background

The trigeminal nerve is the largest cranial nerve and functions in somatosensation. Cell bodies of this nerve are positioned in the trigeminal ganglion, which arises from the coalescence of neural crest and placode cells. While this dual cellular origin has been known for decades, the molecular mechanisms controlling trigeminal ganglion development remain obscure. We performed RNAsequencing on the forming chick trigeminal ganglion and identified Elongator acetyltransferase complex subunit 1 ( Elp1 ) for further study. Mutations in ELP1 cause familial dysautonomia (FD), a fatal disorder characterized by the presence of smaller trigeminal nerves and sensory deficits. While Elp1 has established roles in neurogenesis, its functions in placode cells during trigeminal gangliogenesis have not been investigated.

Results

To this end, we used morpholinos to deplete Elp1 from chick trigeminal placode cells. Elp1 knockdown decreased trigeminal ganglion size and led to aberrant innervation of the eye by placode-derived neurons. Trigeminal nerve branches exhibited fewer axons, and abnormal interactions between placode-derived neurons and neural crest cells were observed.

Conclusions

These findings reveal a new role for Elp1 in chick placode-derived neurons during trigeminal ganglion development. These results have potential high significance to provide new insights into trigeminal ganglion development and the etiology of FD.

Bullet points

Elp1 is expressed in undifferentiated neural crest cells and placode-derived neurons contributing to the trigeminal ganglion.Elp1 knockdown in trigeminal placode cells reduces trigeminal ganglion size.Elp1 depletion from trigeminal placode cells leads to aberrant target tissue innervation and disrupts proper neural crest-placodal neuron interactions in the trigeminal ganglion.

Grant sponsor and number

NIH R01DE024217 and NIH R03HD108480.

Quantitative magnetic resonance evaluation of the trigeminal nerve in familial dysautonomia

PURPOSE

Familial dysautonomia (FD) is a rare autosomal recessive disease that affects the development of sensory and autonomic neurons, including those in the cranial nerves. We aimed to determine whether conventional brain magnetic resonance imaging (MRI) could detect morphologic changes in the trigeminal nerves of these patients.

METHODS

Cross-sectional analysis of brain MRI of patients with genetically confirmed FD and age- and sex-matched controls. High-resolution 3D gradient-echo T1-weighted sequences were used to obtain measurements of the cisternal segment of the trigeminal nerves. Measurements were obtained using a two-reader consensus.

RESULTS

Twenty pairs of trigeminal nerves were assessed in ten patients with FD and ten matched controls. The median (interquartile range) cross-sectional area of the trigeminal nerves in patients with FD was 3.5 (2.1) mm², compared to 5.9 (2.0) mm² in controls (P < 0.001). No association between trigeminal nerve area and age was found in patients or controls.

CONCLUSIONS

Using conventional MRI, the caliber of the trigeminal nerves was significantly reduced bilaterally in patients with FD compared to controls, a finding that appears to be highly characteristic of this disorder. The lack of correlation between age and trigeminal nerve size supports arrested neuronal development rather than progressive atrophy.

Respiratory care in familial dysautonomia: Systematic review and expert consensus recommendations

BACKGROUND

Familial dysautonomia (Riley-Day syndrome, hereditary sensory autonomic neuropathy type-III) is a rare genetic disease caused by impaired development of sensory and afferent autonomic nerves. As a consequence, patients develop neurogenic dysphagia with frequent aspiration, chronic lung disease, and chemoreflex failure leading to severe sleep disordered breathing. The purpose of these guidelines is to provide recommendations for the diagnosis and treatment of respiratory disorders in familial dysautonomia.

METHODS

We performed a systematic review to summarize the evidence related to our questions. When evidence was not sufficient, we used data from the New York University Familial Dysautonomia Patient Registry, a database containing ongoing prospective comprehensive clinical data from 670 cases. The evidence was summarized and discussed by a multidisciplinary panel of experts. Evidence-based and expert recommendations were then formulated, written, and graded using the Grading of Recommendations, Assessment, Development, and Evaluation (GRADE) system.

RESULTS

Recommendations were formulated for or against specific diagnostic tests and clinical interventions. Diagnostic tests reviewed included radiological evaluation, dysphagia evaluation, gastroesophageal evaluation, bronchoscopy and bronchoalveolar lavage, pulmonary function tests, laryngoscopy and polysomnography. Clinical interventions and therapies reviewed included prevention and management of aspiration, airway mucus clearance and chest physical therapy, viral respiratory infections, precautions during high altitude or air-flight travel, non-invasive ventilation during sleep, antibiotic therapy, steroid therapy, oxygen therapy, gastrostomy tube placement, Nissen fundoplication surgery, scoliosis surgery, tracheostomy and lung lobectomy.

CONCLUSIONS

Expert recommendations for the diagnosis and management of respiratory disease in patients with familial dysautonomia are provided. Frequent reassessment and updating will be needed.

Oral manifestations, dental management, and a rare homozygous mutation of the PRDM12 gene in a boy with hereditary sensory and autonomic neuropathy type VIII: a case report and review of the literature

BACKGROUND

Hereditary sensory and autonomic neuropathy type VIII is a rare autosomal recessive inherited disorder. Chen et al. recently identified the causative gene and characterized biallelic mutations in the PR domain-containing protein 12 gene, which plays a role in the development of pain-sensing nerve cells. Our patient's family was included in Chen and colleagues' study. We performed a literature review of the PubMed library (January 1985 to December 2016) on hereditary sensory and autonomic neuropathy type I to VIII genetic disorders and their orofacial manifestations. This case report is the first to describe the oral manifestations, and their treatment, of the recently discovered hereditary sensory and autonomic neuropathy type VIII in the medical and dental literature.

CASE PRESENTATION

We report on the oral manifestations and dental management of an 8-month-old white boy with hereditary sensory and autonomic neuropathy-VIII over a period of 16 years. Our patient was homozygous for a mutation of PR domain-containing protein 12 gene and was characterized by insensitivity to pain and thermal stimuli, self-mutilation behavior, reduced sweat and tear production, absence of corneal reflexes, and multiple skin and bone infections. Oral manifestations included premature loss of teeth, associated with dental traumata and self-mutilation, severe soft tissue injuries, dental caries and submucosal abscesses, hypomineralization of primary teeth, and mandibular osteomyelitis.

CONCLUSIONS

The lack of scientific knowledge on hereditary sensory and autonomic neuropathy due to the rarity of the disease often results in a delay in diagnosis, which is of substantial importance for the prevention of many complications and symptoms. Interdisciplinary work of specialized medical and dental teams and development of a standardized treatment protocols are essential for the management of the disease. There are many knowledge gaps concerning the management of patients with hereditary sensory and autonomic neuropathy-VIII, therefore more research on an international basis is needed.

Autoextraction of twelve permanent teeth in a child with autistic spectrum disorder

BACKGROUND

This report discusses self-injurious behaviour; this is not unusual in people with autistic spectrum disorders but is not commonly experienced as autoextraction.

CASE REPORT

This case concerns a 12 year old child who presented as a new patient with two teeth missing. He then went on to remove a further ten teeth over a relatively short space of time.

CONCLUSION

The recognition of autoextraction by the dental team is important. its management involves a multidisciplinary team which includes professionals from education, health and social care who work together to prevent progressive self-injury.

Oral self-injuries: clinical findings in a series of 19 patients

Objectives: Self-injury (SI) is defined as a behavioral disturbance consisting of a deliberate harm to one’s own body without suicidal intent, it is not uncommon and ranges in severity from simple nail-biting to more extreme forms of self-mutilation. The head neck region may be the target of such lesions. SI is associated with several medical conditions, of which it can represent the first clinical sign. Aim of this paper is to describe a series of oral SI, giving special emphasis to the clinical findings, etiology and the management of lesions. Material and Methods: A total of 19 patients with oral SI were prospectively examined; attention was paid to the occurrence and characterization of oral lesions. The management of the lesion also varied depending on the patient medical history, on the etiology of the psychiatric behavior, and on the severity, frequency, and method of inflicting injury. Periodic examinations were performed (after two weeks, three months and six months) and registered. Results: All the patients healed gradually and healing was conditioned by the disease underlying. The treatment consisted of behavior modification in 11 cases, pharmacological treatment in 11 cases, psychotherapy in 2 cases, mouth guard in 9 cases, surgery in 2 cases, extractions in 1 case. Conclusions: Oral SI are uncommon in the clinical practice. They may be associated with a known disease or may be the consequence of this, but often they may be the first sign of a psychiatric disorder.

Key words:Oral self-mutilation, self-inflicted lesions, self-injurious behavior, ulcers, Obsessive-Compulsive Disorder, mental retardation.

Brainstem reflexes in patients with familial dysautonomia

OBJECTIVE

Several distinctive clinical features of patients with familial dysautonomia (FD) including dysarthria and dysphagia suggest a developmental defect in brainstem reflexes. Our aim was to characterize the neurophysiological profile of brainstem reflexes in these patients.

METHODS

We studied the function of sensory and motor trigeminal tracts in 28 patients with FD. All were homozygous for the common mutation in the IKAP gene. Each underwent a battery of electrophysiological tests including; blink reflexes, jaw jerk reflex, masseter silent periods and direct stimulation of the facial nerve. Responses were compared with 25 age-matched healthy controls.

RESULTS

All patients had significantly prolonged latencies and decreased amplitudes of all examined brainstem reflexes. Similar abnormalities were seen in the early and late components. In contrast, direct stimulation of the facial nerve revealed relative preservation of motor responses.

CONCLUSIONS

The brainstem reflex abnormalities in FD are best explained by impairment of the afferent and central pathways. A reduction in the number and/or excitability of trigeminal sensory axons is likely the main problem.

SIGNIFICANCE

These findings add further evidence to the concept that congenital mutations of the elongator-1 protein (or IKAP) affect the development of afferent neurons including those carrying information for the brainstem reflex pathways.

A review of the oro-dento-facial characteristics of hereditary sensory and autonomic neuropathy type III (familial dysautonomia)

The oro-dento-facial features and dysfunction of children with hereditary sensory and autonomic neuropathy type III, known as familial dysautonomia or Riley-Day syndrome, was first described in the scientific literature in 1949. They include dental trauma; dental and soft tissue self-mutilation; normal dental age; normal sequence and timing of eruption and exfoliation of teeth; smaller tooth size; different and disproportional tooth components; normal alveolar bone height; small jaws, mild crowding, and malocclusions. These persons have craniofacial morphology that is different from accepted norms but they resemble norms of their ethnic origin. The subjects can have gray, pale, shiny faces with an asymmetric suffering expression; frontal bossing, with eventual hypertelorism and narrow lips; a low-caries rate; drooling, and hypersalivation. They can have changes in salivary composition and content, which influences plaque and calculus and increases the risk of gingival and periodontal diseases. They also have difficulty in controlling oral muscles; a progressive decrease in number of tongue fungiform papillae, accompanied by lack of taste buds; and specific dysgeusia, but a normal sense of smell.

Pediatric psychocutaneous disorders: a review of primary psychiatric disorders with dermatologic manifestations

Psychocutaneous disorders (PCDs) are conditions that are characterized by psychiatric and skin manifestations. Classifications of PCDs and their nomenclature are matters of debate. For the purpose of this review, we adopted the classification that distinguishes primary dermatologic disorders with psychiatric co-morbidity (PDDPC) from primary psychiatric disorders with dermatologic manifestations (PPDDM). PDDPC includes the psychophysiologic disorders such as atopic eczema, psoriasis, vitiligo, and alopecia areata. PPDDM includes impulse control disorders, obsessive-compulsive disorders, factitious disorder, factitious disorder by proxy, self-mutilation, delusions of parasitosis, psychogenic purpura/Gardner-Diamond syndrome, and cutaneous sensory disorders. Diagnosis and treatment of PCDs are challenging and require that the underlying psychopathology be addressed. A specific PCD may have different underlying psychopathologies and, at times, multiple overlapping psychopathologies may coexist. Most often, both non-pharmacologic management and psychopharmacologic treatment are necessary. The choice of psychopharmacologic agent depends on the nature of the underlying psychopathology (e.g. anxiety, depression, obsessive-compulsive disorder, psychosis). This article reviews the spectrum of PPDDM in children.

Oral self-injurious behaviors in patients with developmental disabilities

Self-injurious behaviors (SIB) in patients who have developmental disabilities is a complex disorder, and its underlying etiologies are poorly understood. SIB is a significant factor in hospitalizations, decisions to use psychotropic medications, and institutional placement for people who have developmental disabilities. Because this group often manifests oral SIB, the dentist may be the first professional called upon to evaluate a patient. Dental therapy focuses on symptomatic treatment to minimize tissue damage caused by SIB, but addressing the underlying impetus for the behavior is essential for successful treatment. Determining definitive therapeutic interventions is difficult because of the mixed bio behavioral etiologies for SIB. This complication necessitates a team approach that includes medical and behavioral specialists.

Congenital insensitivity-to-pain with anhidrosis (CIPA): A case report with 4-year follow-up

Congenital Insensitivity-to-pain with anhidrosis (CIPA) is a rare disorder in which pain perception is absent from birth, despite the fact that all other sensory modalities remain intact or minimally impaired and tendon reflexes are present. The challenge in dentistry is to manage the self-mutilation behavior avoiding serious damages especially to oral structures, hands and fingers. A Brazilian case of CIPA is presented and discussed with clinical documentation of the oral-related problems over a 4-year follow-up. A conservative treatment (mouthguard-like appliance) was proposed with the objective to avoid full mouth extraction.

Autoextraction in a child with autistic spectrum disorder

Many children with mild/moderate autistic spectrum disorder (ASD) receive care in general dental practice. We report a seven year old boy with ASD presenting with dental pain who auto-extracted one of his deciduous canines. Children with ASD may have hyposensitivity to pain and can exhibit unusual forms of self-injurious behaviour.

Factitial oral lesions in an autistic paediatric patient

Self Injurious Behaviour (SIB) is a deliberate harm to the body that may lead to factitial injuries. Its origin may be functional or biological and it has a higher prevalence in females and in psychologically impaired individuals. Seventy per cent of autistic patients have SIB. Seventy-five per cent of factitial injuries are located in the head and neck region. A paediatric case report concerning a 4-year-old autistic female is presented. Detailed medical history, physical examination, clinical intraoral and radiographic examination, incisional biopsy, neuropaediatrical, psychological and speech evaluation were undertaken. Diagnosis included hypochromic macrocytic anaemia, caries, coronal fracture, factitial ulcer, factitial periodontitis, self-extraction of primary teeth and permanent teeth buds, non-specific oral ulcer with inflammatory reaction, mild mental retardation, speech impairment, autistic syndrome and self injurious behaviour consisting of putting fingers and foreign objects in the gingiva, fingernail biting and hair pulling. Differential diagnosis included hystiocitosis X, prepuberal periodontitis and leukocyte adhesion deficiency. Dental preventive and restorative treatment was performed. Non-contingent reinforcement therapy was successfully used to diminish SIB. Treatment of factitial oral injuries must be interdisciplinary and requires cooperation of the patient, the parents, health care providers, and medical team.

Extensive Riga-Fede disease of the lip and tongue

Riga-Fede disease presents in early infancy and is characterized by firm, verrucous plaques arising on the oral mucosal surfaces. These histologically benign lesions occur as a result of repetitive trauma of the oral mucosal surfaces by the teeth. Early recognition of this entity is important, because it may be the presenting sign of an underlying neurologic disorder. We report the case of a 10-month-old boy with extensive Riga-Fede disease involving the lip and tongue that prompted a diagnosis of congenital autonomic dysfunction with universal pain loss.

Oral manifestations of hereditary sensory and autonomic neuropathy type IV. Congenital insensitivity to pain with anhidrosis

OBJECTIVE

Hereditary sensory and autonomic neuropathy type IV (congenital insensitivity to pain with anhidrosis) is a rare disorder. In this study, we investigated the oral and dental manifestations associated with hereditary sensory and autonomic neuropathy type IV.

STUDY DESIGN

Eighteen patients with hereditary sensory and autonomic neuropathy type IV whose ages ranged from 1 year 0 months to 22 years 3 months were examined for oral signs and symptoms of tooth abnormalities, malocclusions, soft tissue disorders, tongue papilla atrophy, and morphologic abnormalities of hands and fingers.

RESULTS

All 18 patients showed congenital insensitivity to pain and anhidrosis. Oral self-mutilations, such as autoextraction of teeth and severe biting injuries (with resultant scarring) of the finger tips and oral soft tissues (tongue, lip, and buccal mucosa), were found in most patients. In infant patients the condition was typically characterized by decubital ulcers on the ventral surface of the tongue, resulting from trauma of the incisal edge of erupting mandibular primary incisors during sucking or nursing. These ulcers led to several local and systemic problems, such as tongue bleeding, infection, malnutrition, and halitosis. A large number of missing teeth and a high incidence of dental caries were additional characteristic findings. Such oral self-mutilations were found to decrease with age and with the intellectual, social, and/or emotional development of the patients. However, not all of the mutilations were completely eliminated. Two patients had partial dentures to replace missing teeth.

CONCLUSIONS

Our study suggests that early diagnosis and specific dental management for patients with hereditary sensory and autonomic neuropathy type IV are important for prevention of the characteristic oral and dental problems accompanying this disorder.

A cephalometric evaluation of craniofacial morphology in familial dysautonomia

OBJECTIVE

The purpose of this study was to delineate the craniofacial and dentoalveolar morphology of patients with familial dysautonomia (FD) in order to contribute to the understanding of the association between progressive sensory and autonomic neuropathy and the characteristic appearance of the dysautonomic face.

PATIENTS

The study group comprised 32 patients with FD (15 females and 17 males; mean age 10.8 years, SD 3.5 years, range 5.8-19.8 years).

DESIGN

Lateral cephalograms from each patient were traced twice. The means of the two measurements were compared with homologous cephalometric normal values of ethnic-specific and classical norms from the literature.

RESULTS

In some parameters, the craniofacial morphology of the FD group was significantly different from the classical norms. There was a pronounced retrognathism in the mandible and a steep mandibular plane angle. The skeletal features of FD patients more closely resembled those of their ethnic group, although they were more retrognathic, and the mandibular growth axis was more horizontal. The incisors of these patients were more retropositioned and retroclined than were those of their healthy counterparts.

CONCLUSIONS

The results suggest an insufficiency of the expected dentoalveolar compensatory mechanism that usually helps to bridge skeletal discrepancies. It is postulated that the neuropathy is probably the important factor in the lack of this compensatory mechanism.

Role of psychiatric disorders in self-inflicted periodontal injury: a case report

Self-inflicted or factitious injuries (FI) are not uncommon in psychiatric patients. In general, this kind of behavior is linked to secondary gain. However, the role of underlying psychiatric illness should not be overlooked. Usually, the diagnosis of factitious injury can be confirmed by a careful medical-dental history, clinical appearance of the lesion, laboratory investigations, and response to established treatment protocol. A case is presented in which repetitive injurious behavior resulted in rapid periodontal attachment loss. The lesion responded well to conservative periodontal treatment. The role of underlying psychiatric morbidity leading to repetitive self-injurious behavior is discussed.

Preventing factitious gingival injury in an autistic patient

A 34-year-old man with a history of autism developed a deep gingival cleft. During clinical evaluation, the patient repeatedly scraped the affected area with his fingernail. The lesion's clinical features were consistent with focal inflammatory hyperplasia, periodontal disease and factitious stomatitis. This article describes the case and discusses diagnostic and behavioral issues important in treating any patient whose mental age is impaired.