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Query: UMLS:C0030193 (pain)
 261,466 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Hereditary sensory neuropathies (HSNs) are a group of genetically determined peripheral neuropathies with prominent disturbance of the peripheral sensory neurons. They are characterized by sensory loss, insensitivity to pain, a variable degree of muscle weakness and wasting, as well as autonomic features. Frequent complications are foot ulcerations and infections that may lead to osteomyelitis, followed by necrosis and amputations. Consequently, the hereditary sensory neuropathies have also been termed ulceromutilating neuropathies. On the other hand, in the presence of additional motor weakness, they have been subclassified among the group of Charcot-Marie-Tooth (CMT) disorders. Sporadic and familial cases with different modes of inheritance are known to affect both children and adults. The most prevalent forms of the autosomal dominantly inherited hereditary sensory neuropathies are HSN I and CMT 2b. HSN I is associated with mutations in the SPTLC1 gene, whereas mutations in the RAB7 gene have been identified in CMT 2b. However, at least one more hitherto unknown gene responsible for autosomal-dominant hereditary sensory neuropathies must exist. Autosomal-recessive hereditary sensory neuropathies types III and IV, and probably also type V, result from mutations in the IKBKAP and NTRK1 genes. Very recently, the gene in HSN II (HSN2) has been identified. A spontaneous autosomal-recessive mutation in the Cct4 gene has been reported in the Sprague-Dawley rat strain with early onset sensory neuropathy. Although no curative treatment is available so far, and current therapy is limited to symptom relief, these molecular genetic advances in knowledge about the hereditary sensory neuropathies can be translated into clinical practice by improving diagnosis and genetic counseling. They will also be the basis for functional studies in the future.
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PMID:Hereditary sensory neuropathies. 1531 94

Hereditary sensory and autonomic neuropathy type I (HSAN I) is the most frequent type of hereditary neuropathy that primarily affects sensory neurons. The genetic locus for HSAN I has been mapped to chromosome 9q22.1-22.3 and recently the gene was identified as SPTLC1, encoding serine palmitoyltransferase, long chain base subunit-1. Sequencing in HSAN I families have previously identified mutations in exons 5, 6 and 13 of this gene. We analysed the SPTLC1 gene for mutations in 8 families with HSAN I, 60 individuals with sporadic sensory neuropathy, 6 HSAN II families, 20 Charcot-Marie-Tooth type I families and 20 families with Charcot-Marie-Tooth type II. Six HSAN I families and a single sporadic neuropathy case had an identical SPTLC1 mutation. No mutations were found in the other groups. Genetic haplotyping across the HSAN I critical region in 5 families and the sporadic case suggested a common founder. Several characteristics, previously not widely recognized were identified, including lack of penetrance of the SPTLC1 mutation in some individuals, variability in age of onset along with an earlier age of onset in younger generations, in some patients surprisingly early and often severe motor involvement and an earlier onset characterized by motor involvement with demyelinating features in males compared to females in 4 families. The sensory findings were often disassociated with prominent pain and temperature loss. Neurophysiology mainly showed a sensory axonal neuropathy but in many individuals there was electrical evidence of demyelination. Sural nerve biopsies from six affected individuals and the post-mortem findings in 1 case showed mainly axonal loss. This in depth study on the phenotype of HSAN I in 6 families and a single sporadic case with a common founder identifies a number of poorly recognized features in this disorder and highlights the clinical heterogeneity both within and between families suggesting the influence of other genetic and acquired factors.
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PMID:Clinical, pathological and genetic characterization of hereditary sensory and autonomic neuropathy type 1 (HSAN I). 1636 56

Hereditary sensory neuropathy type I (HSN I) is a slowly progressive neurological disorder characterised by prominent predominantly distal sensory loss, autonomic disturbances, autosomal dominant inheritance, and juvenile or adulthood disease onset. The exact prevalence is unknown, but is estimated as very low. Disease onset varies between the 2nd and 5th decade of life. The main clinical feature of HSN I is the reduction of sensation sense mainly distributed to the distal parts of the upper and lower limbs. Variable distal muscle weakness and wasting, and chronic skin ulcers are characteristic. Autonomic features (usually sweating disturbances) are invariably observed. Serious and common complications are spontaneous fractures, osteomyelitis and necrosis, as well as neuropathic arthropathy which may even necessitate amputations. Some patients suffer from severe pain attacks. Hypacusis or deafness, or cough and gastrooesophageal reflux have been observed in rare cases. HSN I is a genetically heterogenous condition with three loci and mutations in two genes (SPTLC1 and RAB7) identified so far. Diagnosis is based on the clinical observation and is supported by a family history. Nerve conduction studies confirm a sensory and motor neuropathy predominantly affecting the lower limbs. Radiological studies, including magnetic resonance imaging, are useful when bone infections or necrosis are suspected. Definitive diagnosis is based on the detection of mutations by direct sequencing of the SPTLC1 and RAB7 genes. Correct clinical assessment and genetic confirmation of the diagnosis are important for appropriate genetic counselling and prognosis. Differential diagnosis includes the other hereditary sensory and autonomic neuropathies (HSAN), especially HSAN II, as well as diabetic foot syndrome, alcoholic neuropathy, neuropathies caused by other neurotoxins/drugs, immune mediated neuropathy, amyloidosis, spinal cord diseases, tabes dorsalis, lepra neuropathy, or decaying skin tumours like amelanotic melanoma. Management of HSN I follows the guidelines given for diabetic foot care (removal of pressure to the ulcer and eradication of infection, followed by the use of specific protective footwear) and starts with early and accurate counselling of patients about risk factors for developing foot ulcerations. The disorder is slowly progressive and does not influence life expectancy but is often severely disabling after a long duration of the disease.
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PMID:Hereditary sensory neuropathy type I. 1834 18

Pain insensitivity is mediated at the genetic level by the disruption of specific genes associated with neuronal development. Mammalian in vivo and in vitro studies have shown the nerve growth factor (NGF) gene to play an integral role in nerve maintenance and function. Pain insensitivity in humans can be attributed to hereditary sensory and autonomic neuropathies (HSAN) of which there are five classes (HSAN I - HSAN V). The human nerve growth factor beta gene (NGFB) located on chromosome 1p13.2 has been found to cause HSAN V within individuals homozygous for a point mutation in NGFB. Although heterozygotes can display a milder phenotype, this has only been observed in adults. We report a karyotypically normal 5-year-old female with developmental delay, mild facial dysmorphism, and unsteady gait. Pain and thermal insensitivity were noted as were recurrent mouth ulcers, facial flushing, recurrent episodes of increased body temperature and unexplained sweating, indicative of a sensory neuropathy with mild autonomic involvement. Array comparative genomic hybridization (aCGH) analysis revealed a de-novo deletion within chromosome 1p13 of the child involving the NGFB gene. Sequence analysis of the homologous NGFB gene identified no mutation, implying that sensory neuropathy was caused by haploinsufficiency of the NGFB gene.
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PMID:Haploinsufficiency of the nerve growth factor beta gene in a 1p13 deleted female child with an insensitivity to pain. 1918 17

Insensitivity to pain is a rare disorder that is commonly associated with Hereditary Sensory and Autonomic Neuropathies (HSAN I-V) resulting often in autonomic dysfunction and premature death. Very few individuals have been reported with pain insensitivity lacking such autonomic neuropathies. We performed genetic, neurologic, psychological, and psychophysical evaluations in such an individual (OMIM 243000) and her first degree relatives. Sequence analysis of genomic DNA revealed two novel SCN9A mutations in this index case (IC). One was a non-conservative missense mutation (C1719R) in exon 26 present only in the IC and one parent. Further sequence analysis of the child's DNA revealed a 1-bp splice donor deletion in intron 17 which was also present in the other parent and one sibling. Detailed psychophysical testing was used to phenotypically characterize the IC, her family members, and 10 matched normal controls. Similar to family members and controls the IC showed normal somatosensory functioning for non-nociceptive mechanoreception and warmth. However, she demonstrated diminished ability to detect cool temperatures combined with profound deficits in heat and mechanical nociception. Congenital insensitivity to pain in our IC was associated with two novel SCN9A mutations which most likely resulted in a Nav1.7 channelopathy. However, in contrast to individuals with other SCN9A mutations, the observed pain insensitivity was relative and not absolute, which may be consistent with hypomorphic effects of one or both mutations. The ability to sense at least some danger signals may be advantageous and ameliorate the otherwise increased morbidity and mortality of some individuals with congenital insensitivity to pain.
Eur J Pain 2011 Mar
PMID:Two novel mutations of SCN9A (Nav1.7) are associated with partial congenital insensitivity to pain. 2069 58

Hereditary sensory and autonomic neuropathy type I (HSAN I) is an autosomal dominant disease characterized by distal sensory loss, pain insensitivity, and autonomic disturbances. The major underlying causes of HSAN I are point mutations in the SPTLC1 gene. Patients with mutations in the SPTLC1 genes typically exhibit dense sensory loss and incidence of lancinating pain. Although most of these mutations produce sensory loss, it is unclear which mutations would lead to the painful phenotype. In this case series, we report that the V144D mutation in SPTLC1 gene may relate to both painful and painless peripheral neuropathies. The unique clinical phenotype of this mutation may guide clinical workup and treatment for patients with painful and painless neuropathies.
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PMID:V144D Mutation of SPTLC1 Can Present with Both Painful and Painless Phenotypes in Hereditary Sensory and Autonomic Neuropathies Type I. 3042 Sep 26