Congenital absence of touch does not preclude normal cognitive and socioemotional development.

Attachment theory holds that development of normal affective and social behavior requires physical contact between infant and caregiver. The elevation of touch to paramount importance has gone unchallenged because, prior to the present study, no individual with a congenital lack of somatosensation has been reported, much less studied for psychosocial development. Here we describe Kim, who since birth, has been unable to perceive touch, temperature changes, or pain on the body surface. Despite her inability to sense physical contact, Kim has above-average intelligence. She functions normally in social situations with a variety of people, recognizing emotions in herself and others and demonstrating appropriate affect. Kim experiences anxiety that appears grounded in realistic fears and uncertainties particular to her somatic insensitivity, thus serving as adaptive vigilance in reaction to an abnormal sensorium. Her normal socioemotional development, evident from an early age, likely resulted from Kim being able to appreciate her parents' loving care through gaze, movement, and hearing. In sum, Kim upends the idea of touch as critical to developing a sense of self, secure attachment, and family bonds.

Congenital insensitivity to pain associated with PRDM12 mutation: Two case reports and a literature review.

Background: PRDM12 is a newly discovered gene responsible for congenital insensitivity to pain (CIP). Its clinical manifestations are various and not widely known. Methods: The clinical data of two infants diagnosed with CIP associated with PRDM12 mutation were collected. A literature review was performed, and the clinical characteristics of 20 cases diagnosed with a mutation of PRDM12 were summarized and analyzed. Results: Two patients had pain insensitivity, tongue and lip defects, and corneal ulcers. The genomic analysis results showed that variants of PRDM12 were detected in the two families. The case 1 patient carried heterozygous variations of c.682+1G > A and c.502C > T (p.R168C), which were inherited from her father and mother, respectively. We enrolled 22 patients diagnosed with CIP through a literature review together with our cases. There were 16 male (72.7%) and 6 female (27.3%) patients. The age of onset ranged from 6 months to 57 years. The prevalence of clinic manifestation was 14 cases with insensitivity to pain (63.6%), 19 cases with self-mutilation behaviors (86.4%), 11 cases with tongue and lip defects (50%), 5 cases with mid-facial lesions (22.7%), 6 cases with distal phalanx injury (27.3%), 11 cases of recurrent infection (50%), 3 cases (13.6%) with anhidrosis, and 5 cases (22.7%) with global developmental delay. The prevalence of ocular symptoms was 11 cases (50%) with reduced tear secretion, 6 cases (27.3%) with decreased corneal sensitivity, 7 cases (31.8%) with disappeared corneal reflexes, 5.5 cases (25%, 0.5 indicated a single eye) with corneal opacity, 5 cases (22.7%) with corneal ulceration, and 1 case (4.5%) with a corneal scar. Conclusion: The syndrome caused by PRDM12 mutation is a clinically distinct and diagnosable disease that requires joint multidisciplinary management to control the development of the disease and minimize the occurrence of complications.

Congenital corneal anesthesia: A case series.

Congenital corneal anesthesia (CCA) is an extremely rare condition where the cornea is affected in isolation or as a part of congenital syndrome, or can be associated with systemic anomalies. This case series of 12 eyes provides an overview of various clinical presentations and their final treatment outcomes. The average age of presentation was 3.2 years with a female preponderance (75%). Fifty percent of the patients had bilateral involvement and 50% had corneal ulcers at presentation. Two eyes required therapeutic keratoplasty for corneal perforation. All patients had isolated CCA except for one who had an associated hereditary and sensory autonomic neuropathy.

Pathogenic DST sequence variants result in either epidermolysis bullosa simplex (EBS) or hereditary sensory and autonomic neuropathy type 6 (HSAN-VI).

DST encodes bullous pemphigoid antigen-1 (BPAG1), a protein with eight tissue-specific isoforms expressed in the skin, muscle, brain and nerves. Accordingly, mutations in this gene are associated with epidermolysis bullosa simplex (EBS) and hereditary sensory and autonomic neuropathy type 6 (HSAN-VI). The genotypic spectrum is attested to by 19 distinct mutations but genotype-phenotype correlation for both disorders is not well established. In this study, we performed next-generation sequencing (NGS) on two families with different phenotypic presentations, one foetus (P1) with musculoskeletal and neurological malformations established by prenatal ultrasound and family history, and a 15-year-old female patient (P2) with skin blistering. P1 had a novel homozygous nonsense mutation, DST: NM_001144769, c.3805C>T, p.R1269* within a region of genetic homozygosity (ROH). This mutation resides within the plakin domain of BPAG1 and ablates all isoforms of this protein, leading to novel extracutaneous phenotypes consistent with HSAN-VI in P1. P2 had a recurrent homozygous mutation DST: NM_001723.7, c.3370C>T, p.Gln1124* that presented with giant, trauma-induced skin blisters without extracutaneous involvement. This mutation is located within the coiled-coil domain present in the skin isoform of DST, BPGA1-e, associated with EBS. In summary, we report two families with pathogenic DST variants and expand the spectrum of DST genotype and phenotypes.

Clinical, neuroimaging, and molecular spectrum of TECPR2-associated hereditary sensory and autonomic neuropathy with intellectual disability.

Bi-allelic TECPR2 variants have been associated with a complex syndrome with features of both a neurodevelopmental and neurodegenerative disorder. Here, we provide a comprehensive clinical description and variant interpretation framework for this genetic locus. Through international collaboration, we identified 17 individuals from 15 families with bi-allelic TECPR2-variants. We systemically reviewed clinical and molecular data from this cohort and 11 cases previously reported. Phenotypes were standardized using Human Phenotype Ontology terms. A cross-sectional analysis revealed global developmental delay/intellectual disability, muscular hypotonia, ataxia, hyporeflexia, respiratory infections, and central/nocturnal hypopnea as core manifestations. A review of brain magnetic resonance imaging scans demonstrated a thin corpus callosum in 52%. We evaluated 17 distinct variants. Missense variants in TECPR2 are predominantly located in the N- and C-terminal regions containing ß-propeller repeats. Despite constituting nearly half of disease-associated TECPR2 variants, classifying missense variants as (likely) pathogenic according to ACMG criteria remains challenging. We estimate a pathogenic variant carrier frequency of 1/1221 in the general and 1/155 in the Jewish Ashkenazi populations. Based on clinical, neuroimaging, and genetic data, we provide recommendations for variant reporting, clinical assessment, and surveillance/treatment of individuals with TECPR2-associated disorder. This sets the stage for future prospective natural history studies.

The painless eye: Neurotrophic keratitis in a child suffering from hereditary sensory autonomic neuropathy type IV.

Hereditary sensory autonomic neuropathy (HSAN) is a group of inherited disorders (total 5 types) that are associated with sensory dysfunction and varying degrees of autonomic dysfunction. HSAN type IV (HSAN-IV) or congenital insensitivity to pain and anhidrosis (CIPA) is a rare genetic disorder inherited in an autosomal recessive manner. We report a case of this very rare genetic disease in a 3-year-old girl child, born to a family in north India with ocular features of neurotrophic keratitis. The diagnosis was made clinically based on the hallmark features of insensitivity to pain and temperature, anhidrosis, self-mutilating behavior with multiple recurrent oral ulcers, nasal bleeds, multiple trophic ulcers over joints, and decreased intellect.

FLVCR1-related disease as a rare cause of retinitis pigmentosa and hereditary sensory autonomic neuropathy.

FLVCR1 encodes for a transmembrane heme exporter protein and it is known to cause a rare form of syndromic retinitis pigmentosa: posterior column ataxia with retinitis pigmentosa. Recently, the FLVCR1-associated phenotype has been expanded with sporadic reports of hereditary sensory-autonomic neuropathy or non-syndromic retinitis pigmentosa. Here, we report a 23-year- old female with early onset hypomyelinating sensory-autonomic neuropathy and retinitis pigmentosa. Both features were present since childhood. The patient developed signs of advanced retinitis pigmentosa by the age of 10 years leading to legal blindness after the age of 18. Following candidate gene panel testing, which was negative, whole exome sequencing revealed compound heterozygous pathogenic FLVCR1 variants: NM_014053.3: c.3G > T; p.(Met1?) and NM_014053.3: c.730G > A; p.(Gly244Ser), the latter variant is novel. In this report we highlight the association of retinitis pigmentosa with hypomyelinating sensory-autonomic neuropathy, which could be underdiagnosed due to variable severity. To summarize, the phenotypic heterogeneity of FLVCR1 variants is broad and should include retinitis pigmentosa along with range of neurological features.

A missense point mutation in nerve growth factor (NGFR100W) results in selective peripheral sensory neuropathy.

The R100W mutation in nerve growth factor is associated with hereditary sensory autonomic neuropathy V in a Swedish family. These patients develop severe loss of perception to deep pain but with apparently normal cognitive functions. To better understand the disease mechanism, we examined a knockin mouse model of HSAN V. The homozygous mice showed significant structural deficits in intra-epidermal nerve fibers (IENFs) at birth. These mice had a total loss of pain perception at ∼2 months of age and often failed to survive to adulthood. Heterozygous mutant mice developed a progressive degeneration of small sensory fibers both behaviorally and functionally: they showed a progressive loss of IENFs starting at the age of 9 months accompanied with progressive loss of perception to painful stimuli such as noxious temperature. Quantitative analysis of lumbar 4/5 dorsal root ganglia revealed a significant reduction in small size neurons, while analysis of sciatic nerve fibers revealed the heterozygous mutant mice had no reduction in myelinated nerve fibers. Significantly, the amount of NGF secreted from mouse embryonic fibroblasts were reduced from both heterozygous and homozygous mice compared to their wild-type littermates. Interestingly, the heterozygous mice showed no apparent structural alteration in the brain: neither the anterior cingulate cortex nor the medial septum including NGF-dependent basal forebrain cholinergic neurons. Accordingly, these animals did not develop appreciable deficits in tests for brain function. Our study has thus demonstrated that the NGFR100W mutation likely affects the structure and function of peripheral sensory neurons.

Conservative Treatment or Surgical Treatment: A Case Report and Literature Review of Multiple Fractures of the Lower Extremities in a Child with Insensitivity to Pain.

Congenital pain insensitivity is a rare genetic disease and its clinical manifestations are many. In orthopaedics, common complications of this disease include painless fracture and Charcot's arthropathy. We followed up a case of multiple fractures of the lower extremity in two years, during which time he came to the clinic for five painless fractures of the lower extremity in a total of six parts. A mutation was found on the NTKRI gene (chr1:156813923(hg19), NM_001007792.1: c.1221938C > T). We have developed a combination of surgery and conservative treatments for his condition, focusing on the mental state of the child and considering comprehensive treatment to be the best option for this type of patient. Occult fractures caused by pain insensitivity are often treated only as fractures, however their complications require routine examination and cleaning, suitable protective shoes, splint fixation, stretching, guided exercise planning, and early treatment of injuries. Due to the risk of fracture in the future, it is important that parents pay attention to the behavior and psychology of the child, such as not letting the child participate in exercise with a risk of injury, protective measures while playing, engaging in psychological counseling, and inducing interest in mental activity. These interventions will play a very important role in preventing the recurrence of fracture.

Hereditary sensory autonomic neuropathy type II: Report of two novel mutations in the FAM134B gene.

Hereditary sensory autonomic neuropathy (HSAN) type II is a rare, autosomal recessive, and early onset sensory neuropathy, characterized by severe and progressive sensation impairment, leading to ulcero-mutilating complications. FAM134B gene, also known as RETREG1 gene, mutations have been reported to be associated to HSAN-IIB. We report four patients from two unrelated families who developed during childhood a sensory axonal neuropathy with variable severity and pronounced nociception impairment. Complications such as recurrent ulcerations, osteomyelitis, and osteonecrosis leading to distal amputation were noticed. Dysautonomia was mild or even absent in our group of patients. Additionally, either clinical or neurophysiological motor impairment was not uncommon. Presence of upper motor neuron signs was also a distinctive feature in two related patients. After extensive workup, two novel homozygous mutations in the FAM134B gene were identified. This report expands the clinical and genetic spectrum of HSAN type II and emphasizes the phenotype variability even within the same family.

Wilson Disease Comorbid with Hereditary Sensory Autonomic Neuropathy Type IV and Gitelman Syndrome.

Wilson disease a rare autosomal recessive inherited disorder of copper metabolism, is characterized by excessive deposition of copper in the liver, brain, and other tissues. Wilson disease is often fatal if it is not recognized early and treated when it is symptomatic. Gitelman syndrome is also an autosomal recessive kidney disorder characterized by low blood levels of potassium and magnesium, decreased excretion of calcium in the urine, and elevated blood pH. Hereditary sensory autonomic neuropathy type IV (HSAN-IV), a very rare condition that presents in infancy, is characterized by anhidrosis, absence of pain sensation, and self-mutilation. It is usually accompanied by developmental delay and mental retardation. We report a case of Wilson disease manifested as fulminant hepatitis, acute pancreatitis, and acute kidney injury in a 15-year-old boy comorbid with HSAN-IV and Gitelman syndrome. Such concurrence of three genetic diseases is an extremely rare case.

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.

Cholinergic striatal neurons are increased in HSAN V homozygous mice despite reduced NGF bioavailability.

The neurotrophin Nerve growth factor (NGF) plays a critical role in the mature and developing nervous system. A point mutation (R100W) in the NGFB gene was found in patients with Hereditary Sensory and Autonomic Neuropathy type V (HSAN V), which leads to pain insensitivity. In a previous work it has been shown that the mutation provokes a reduced secretion of mature NGF. In this study we generated and analyzed homozygous NGFR100W/R100W mice to understand whether the reduced NGF bioavailability can contribute to the clinical phenotype of the homozygous condition. We found that the majority of NGFR100W/R100W mice were born normal but failed to reach the first month of age. This early lethality was rescued by daily treatment with wild type NGF. In addition, we found that the density of cholinergic neurons of homozygous mice was unaffected in the medial septum and in the nucleus basalis of Meynert, whereas, suprisingly, it was increased specifically in the striatum. Due to the known action of the striatal cholinergic tone in modulating pain, our findings support the hypothesis that a central mechanism, linked to the NGFR100W-dependent increase of the striatal cholinergic tone, can contribute to the pain insensitivity observed in HSAN V patients.

Wilson Disease Comorbid with Hereditary Sensory Autonomic Neuropathy Type IV and Gitelman Syndrome / 대한소아소화기영양학회지

Wilson disease a rare autosomal recessive inherited disorder of copper metabolism, is characterized by excessive deposition of copper in the liver, brain, and other tissues. Wilson disease is often fatal if it is not recognized early and treated when it is symptomatic. Gitelman syndrome is also an autosomal recessive kidney disorder characterized by low blood levels of potassium and magnesium, decreased excretion of calcium in the urine, and elevated blood pH. Hereditary sensory autonomic neuropathy type IV (HSAN-IV), a very rare condition that presents in infancy, is characterized by anhidrosis, absence of pain sensation, and self-mutilation. It is usually accompanied by developmental delay and mental retardation. We report a case of Wilson disease manifested as fulminant hepatitis, acute pancreatitis, and acute kidney injury in a 15-year-old boy comorbid with HSAN-IV and Gitelman syndrome. Such concurrence of three genetic diseases is an extremely rare case.

Targeted Mutation (R100W) of the Gene Encoding NGF Leads to Deficits in the Peripheral Sensory Nervous System.

Nerve growth factor (NGF) exerts multifaceted functions through different stages of life. A missense mutation (R100W) in the beta-NGF gene was found in hereditary sensory autonomic neuropathy V (HSAN V) patients with severe loss of pain perception but without overt cognitive impairment. To better understand the pathogenesis of HSAN V, we generated the first NGFR100W knock in mouse model for HSAN V. We found that the homozygotes exhibited a postnatal lethal phenotype. A majority of homozygous pups died within the first week. Some homozygous pups could ingest more milk and survived up to 2 months by reducing litter size. Whole mount in situ hybridization using E10.5 embryos revealed that, compared to wild type, R100W mutation did not alter the gene expression patterns of TrkA and P75NTR in the homozygotes. We also found that the homozygotes displayed normal embryonic development of major organs (heart, lung, liver, kidney, and spleen). Furthermore, the homozygotes exhibited severe loss of PGP9.5-positive intra-epidermal sensory fibers. Taken together, our results suggest that, as with HSAN V patients, the R100W mutation primarily affects the peripheral sensory nervous system in the mouse model. This novel mouse model makes it possible to further study in vivo how NGFR100W uncouple trophic function from nociception of NGF.

Two mixed breed dogs with sensory neuropathy are homozygous for an inversion disrupting FAM134B previously identified in Border Collies.

Two unrelated 8-month-old male mixed breed dogs were presented for evaluation of progressive ataxia, knuckling, and lack of pain perception in the distal limbs. Because of the similarity in age of onset, progression, and clinical findings with previously described sensory neuropathy in Border Collies, the affected dogs were screened for an FAM134B mutation and were determined to be homozygous for the mutation. Despite few phenotypic similarities with other breeds, genetic testing for specific diseases should be considered in mixed breed dogs with compatible clinical signs, especially if ancestry is unknown.

Total Hip Arthroplasty in an Inveterate Femoral Neck Fracture in a Patient with Congenital Insensitivity to Pain with Anhidrosis.

Congenital insensitivity to pain with anhidrosis (CIPA) is an extremely rare disorder characterized by autonomic and sensory nerves malfunction with insensitivity to both deep and superficial painful stimuli, inability to sweat and produce tears, and mild to moderate mental retardation with self-mutilating behavior. Related consequences of inveterate musculoskeletal injuries represent a major issue for these patients, since pain cannot act as a protection mechanism. For the same reason, the patients are at risk during postoperative rehabilitation, which should be taken into account when selecting an orthopaedic implant. To our knowledge, only one case of total hip arthroplasty has been reported in the literature to date. A 21-year-old Caucasian male patient affected with CIPA arrived at our attention complaining about a functional limitation of the left hip. No history of trauma was reported. The X-rays showed an inveterate femoral neck fracture with a severe necrosis and resorption of the femoral head. We decided to perform a total hip arthroplasty with a cemented stem and a cemented dual mobility cup. The postoperative course and rehabilitation were satisfactory, with excellent clinical results, measured with the Harris Hip Score at 1 year.

Hereditary Sensory and Autonomic Neuropathy Type IV in 9 Year Old Boy: A Case Report.

Objective The Hereditary Sensory and Autonomic neuropathy (HSAN) is a rare group of neuropathies that affects the Sensory and Autonomic nervous system. The patients do not have the ability of sensing different sensations such as pain and temperature, which tends to lead to different injuries. In addition, due to autonomic involvement, the patients suffer from fluctuation in body temperature periodically and lack of precipitation. HSAN is divided into 5 types according to the age of onset, clinical features, and inheritance. Our case was a 9-yr old boy from cousin parents. He had some developmental delay and history of recurrent fever and convulsion in the first year of his life. Gradually, other symptoms added to patient' feature such as multiple painless skin ulcers, tooth loss, destruction of toes and fingers. In electrodiagnostic study, we found decreased amplitude of sensory nerves, while the other studies were normal. Laboratory test and imaging studies were also normal. All clinical and paraclinical findings were in favor of HSAN type IV. There is no cure for such patients; as a result, these patients and their families need receiving appropriate education and timely rehabilitation services.