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

Homozygosity for a Rare Plec Variant Suggests a Contributory Role in Congenital Insensitivity to Pain

Congenital insensitivity to pain is a rare human condition in which affected individuals do not experience pain throughout their lives. This study aimed to identify the molecular etiology of congenital insensitivity to pain in two Thai patients. Clinical, radiographic, histopathologic, immunohistochemical, and molecular studies were performed. Patients were found to have congenital insensitivity to pain, self-mutilation, acro-osteolysis, cornea scars, reduced temperature sensation, tooth agenesis, root maldevelopment, and underdeveloped maxilla and mandible. The skin biopsies revealed fewer axons, decreased vimentin expression, and absent neurofilament expression, indicating lack of dermal nerves. Whole exome and Sanger sequencing identified a rare homozygous variant c.4039C>T; p.Arg1347Cys in the plakin domain of Plec, a cytolinker protein. This p.Arg1347Cys variant is in the spectrin repeat 9 region of the plakin domain, a region not previously found to harbor pathogenic missense variants in other plectinopathies. The substitution with a cysteine is expected to decrease the stability of the spectrin repeat 9 unit of the plakin domain. Whole mount in situ hybridization and an immunohistochemical study suggested that Plec is important for the development of maxilla and mandible, cornea, and distal phalanges. Additionally, the presence of dental anomalies in these patients further supports the potential involvement of Plec in tooth development. This is the first report showing the association between the Plec variant and congenital insensitivity to pain in humans.

Case Study of a Rare Genetic Disorder: Congenital Insensitivity to Pain With Anhidrosis

A rare autosomal recessive disorder, congenital insensitivity to pain with anhidrosis, is characterised by the congenital lack of pain sensation. Other characteristic symptoms include no sweating, recurrent episodes of hyperpyrexia, retardation of mental abilities and self-mutilating behaviour. Herein, we present a case of a one-year-old male child who initially presented with self-bites on the tongue and then multiple fractures with no report of pain or crying, which initially indicated carelessness of parents. Based on further in-depth assessment indicating a family history of similar weak bones and no pain, the paediatric team conducted investigations along with genetic tests. The child was diagnosed with congenital insensitivity to pain with anhidrosis. Another sibling born later also had the same disorder. Both the children developed eczema, which was difficult to cure due to constant scratching by children as they did not feel any pain. Follow-up studies indicated a slight difficulty in learning abilities and delay in the achievement of milestones. This case report indicates the need for rigorous investigations in such cases to understand the aetiology and appropriate counselling of parents for the utmost care of the child.

Could Congenital Insensitivity to Pain with Anhidrosis Be Misdiagnosed as Papillon-Lefèvre Syndrome?

Papillon-Lefèvre syndrome (PLS) is a rare autosomal recessive disorder characterized by early loss of teeth with hyperkeratosis of the palms and soles. Congenital insensitivity to pain with anhidrosis (CIPA) is a disorder of decreased pain sensation, decreased sweating, recurrent infections, and fever. Here, we report a 5-year-old girl born to consanguineous parents with a family history of a similarly affected sibling. The girl presented with early loss of teeth and palmoplantar hyperkeratosis, hence, provisionally diagnosed as PLS. Further clinical examination and detailed history taking shifted the diagnosis to CIPA. CIPA could be misdiagnosed as PLS. Congenital insensitivity to pain with anhidrosis, although rare, should be considered in the differential diagnosis of PLS.

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.

Successful treatment of self-inflicted tongue trauma patient using a special oral appliance

A 7-year-old male presented with a painful ulcerative lesion on the right lateral tongue and left lower buccal mucosa due to self-inflicted trauma. Antibiotic medication and use of a mouthwash agent were not effective. We made a special oral appliance to cover the maxillary arch and teeth to protect the tongue. The patient showed immediate improvement and did not suffer from any complications. Invasive procedures such as biopsy were not needed. We believe that accurate clinical diagnosis is important and treatment with an oral appliance is effective in self-inflicted oral trauma in children.

Twins with hereditary sensory and autonomic neuropathy type IV with preserved periodontal sensation

Turkish twin brothers affected with hereditary sensory and autonomic neuropathy type IV (HSAN IV) are reported. Their clinical findings were generally typical for HSAN IV. Interestingly they both had preserved periodontal sensation. Mutation analysis of the NTRK1 gene showed a homozygous c.2001C>T substitution in exon 15 in both twins. This base substitution is predicted to change a polar, positively charged amino acid arginine to the highly active amino acid cystein at position 654 (p.Arg654Cys). The parents were heterozygous for the mutation. This mutation has been reported previously in one Japanese and one Arab patients. The preserved periodontal sensation has not previously been reported in patients affected with HSAN IV. This preserved sensation in our patients might have been through Ruffini endings, the periodontal mechanoreceptors which have been reported to be present in TrkA knockout mice. Here we report the first twins affected with HSAN IV and the observation that periodontal sensation is not affected by mutation in NTRK1.

Facial self-mutilation: an analysis of published cases

OBJECTIVES

Facial self-mutilation is rare. It is usually discussed from the psychiatric or psychoanalytic perspectives but has little prominence in general medical literature. Our objective was to describe facial self-mutilation in terms of its comorbidities, and to outline the different types of facial mutilation, as well as the basic approach to the patients with facial self-mutilation.

METHODS

We undertook a review of all published cases of facial self-mutilation (1960-2011).

RESULTS

We identified 200 published cases in 123 relevant papers. Four major groups of comorbidities emerged: psychiatric, neurological and hereditary disorders, and a group of patients without identified comorbidities. There were three general patterns of facial self-mutilation: (1) major and definitive mutilation, with the ocular globe as primary target--seen in patients with psychotic disorders; (2) stereotypical mutilation involving the oral cavity and of variable degree of severity, most often seen in patients with hereditary neuropathy or encephalopathy; (3) mild chronic self-mutilation, seen in patients with non-psychotic psychiatric disorders, acquired neurological disorders, and patients without comorbidities. About 20% of patients that mutilated their face also mutilated extra-facial structures. Patients with psychiatric conditions, especially those with psychotic disorders, had significantly higher (p<0.05) rates of permanent facial self-mutilation than others. Most treatment plans were very individually based, but some principles, such as prevention of irreversible loss of function and structure, or development of infection are applicable to all patients with facial self-mutilation.

CONCLUSIONS

Facial self-mutilation is a potentially severe manifestation of diverse conditions. Several aspects of facial self-mutilation remain to be fully characterised from a clinical perspective.

Oral and craniofacial manifestations and two novel missense mutations of the NTRK1 gene identified in the patient with congenital insensitivity to pain with anhidrosis

Congenital insensitivity to pain with anhidrosis (CIPA) is a rare inherited disorder of the peripheral nervous system resulting from mutations in neurotrophic tyrosine kinase receptor 1 gene (NTRK1), which encodes the high-affinity nerve growth factor receptor TRKA. Here, we investigated the oral and craniofacial manifestations of a Chinese patient affected by autosomal-recessive CIPA and identified compound heterozygosity in the NTRK1 gene. The affected boy has multisystemic disorder with lack of reaction to pain stimuli accompanied by self-mutilation behavior, the inability to sweat leading to defective thermoregulation, and mental retardation. Oral and craniofacial manifestations included a large number of missing teeth, nasal malformation, submucous cleft palate, severe soft tissue injuries, dental caries and malocclusion. Histopathological evaluation of the skin sample revealed severe peripheral nerve fiber loss as well as mild loss and absent innervation of sweat glands. Ultrastructural and morphometric studies of a shed tooth revealed dental abnormalities, including hypomineralization, dentin hypoplasia, cementogenesis defects and a dysplastic periodontal ligament. Genetic analysis revealed a compound heterozygosity- c.1561T>C and c.2057G>A in the NTRK1 gene. This report extends the spectrum of NTRK1 mutations observed in patients diagnosed with CIPA and provides additional insight for clinical and molecular diagnosis.

Oral self-injury: an update

BACKGROUND

Self-inflicted oral injuries of organic origin are particularly common in certain diseases, syndromes, and systemic disorders. In this article, we discuss the characteristics of these oral lesions and their treatment.

LITERATURE SEARCH

The authors have reviewed the most relevant literature relating to oral self-injury through a search in textbooks and published articles included in the Medline database for the years 1970-2010, and selected published cases from the last two decades.

RESULTS

The majority of the literature on oral self-injury is in the form of case reports. Self-injury is particularly prevalent in patients with Lesch-Nyhan syndrome, a heterogeneous group of neurological disorders, congenital insensitivity to pain with anhidrosis, and mental retardation. It is most common in males in the early years of life, and the sites most frequently involved are the lower lip and the tongue. Therapeutic approaches in these patients have included psychological and pharmacological treatment, intraoral devices, and surgical procedures.

CLINICAL IMPLICATIONS

Intraoral devices are the best therapeutic option for self-injury of organic origin, although this approach is not free of complications. The current lack of standardized treatment protocols for oral self-injury means that therapy must be individualized.

Congenital Insensitivity to Pain with Anhidrosis (CIPA): A Case Report

Congenital insensitivity to pain with anhidrosis (CIPA) is a rare disorder characterized by episodes of fever and the inability to sense of pain despite the fact that all other sensory modalities remain intact or minimally impaired. The patient also may exhibit the signs of self-mutilation, mental retardation and little or no perspiration. We present a 10 years old Iranian patient diagnosed with CIPA with the above-mentioned clinical characteristics. The prosthetic treatment and the subsequent six month follow-up are discussed. Follow-up of the patient revealed that, with the use of this prosthesis, the patient's oral function and esthetics were established and the mouth lesions improved. Therefore especial dental management of CIPA patients according to their mental status, age, oral and dental condition is essential for solving the specific problems each case may present and the full mouth teeth extraction should be considered as the last treatment.

Novel neurotrophic tyrosine kinase receptor type 1 gene mutation associated with congenital insensitivity to pain with anhidrosis

Congenital insensitivity to pain with anhidrosis (hereditary sensory and autonomic neuropathy type IV) is a rare autosomal recessive disorder caused by a defect in neurotrophic tyrosine kinase receptor and nerve growth factor, as reported in previous studies. This report is of a 6-month-old male infant with typical symptoms and signs of congenital insensitivity to pain with anhidrosis. He had a homozygous insertion mutation with c.2086_2087 ins C of neurotrophic tyrosine kinase receptor type 1 (NTRK1) gene with both parents as heterozygous carriers. This mutation may have a strong relation to hereditary sensory and autonomic neuropathy type IV Taiwanese patients. This is the youngest reported patient in Taiwan and first reported with congenital insensitivity to pain with mutation of NTRK1 gene inherited from the parents. Early diagnosis may provide appropriate medical care and education for these children and their families for better prognosis.

Orthodontic treatment and management of limited mouth opening and oral lesions in a patient with congenital insensitivity to pain: case report

Congenital insensitivity to pain is a rare clinical syndrome characterized by dramatic impairment of pain perception since birth and is generally caused by a hereditary sensory and autonomic neuropathy with loss of the small-calibre, nociceptive nerve fibres. We report a 9-year-old case, with a generalized congenital insensitivity to pain. The patient was referred to our Department by a private orthodontist for severe limited mouth opening and multiple oral ulcers which greatly worsened after starting the orthodontic treatment. The management of his oral lesions of the limited mouth opening and of the orthodontic treatment are described. The management approach aimed to improve mandibular range of motion and associated stretching and a self-modeling mouthguard to avoid cheek self-biting. This protocol allowed continuing the orthodontic treatment to restore the occlusion. Finally, good occlusion, normal function and better quality of patient's life were achieved.