F-waves persistence in peripheral sensory syndromes / Persistência das ondas-F nas síndromes sensitivas periféricas

Abstract Background The distinction between sensory neuronopathies (SN), which is by definition purely sensory, and sensory polyneuropathies (SP) and sensory multineuropathies (SM) is important for etiologic investigation and prognosis estimation. However, this task is often challenging in clinical practice. We hypothesize that F-wave assessment might be helpful, since it is able to detect subtle signs of motor involvement, which are found in SP and SM, but not in SN. Objective The aim of the present study was to determine whether F-waves are useful to distinguish SN from SP and SM. Methods We selected 21 patients with SP (12 diabetes mellitus, 4 transthyretin familial amyloid polyneuropathy, 4 others), 22 with SM (22 leprosy), and 26 with SN (13 immune-mediated, 10 idiopathic, 3 others) according to clinical-electrophysiological-etiological criteria. For every subject, we collected data on height and performed 20 supramaximal distal stimuli in median, ulnar, peroneal, and tibial nerves, bilaterally, to record F-waves. Latencies (minimum and mean) and persistences were compared across groups using the Kruskal-Wallis and Bonferroni tests. P-values < 0.05 were considered significant. Results All groups were age, gender, and height-matched. Overall, there were no significant between-group differences regarding F-wave latencies. In contrast, F-wave persistence was able to stratify the groups. Peroneal F-wave persistence was higher, bilaterally, in the SN group compared to SM and SP (p < 0.05). In addition, F-waves persistence of the ulnar and tibial nerves was also helpful to separate SN from SP (p < 0.05). Conclusion F-wave persistence of the peroneal nerves might be an additional and useful diagnostic tool to differentiate peripheral sensory syndromes.

Resumo Antecedentes A distinção entre neuronopatias sensitivas (SN) e polineuropatias sensitivas (SP) e multineuropatias sensitivas (SM) é importante para a investigação etiológica e para o prognóstico. Contudo, esta tarefa é desafiadora na prática clínica. Hipotetizou-se que a avaliação das ondas-F pode ser útil, por ser capaz de detectar envolvimento motor nas SP e SM, mas não nas SN. Objetivo Determinar se as ondas-F podem ajudar a distinguir entre SN, SP e SM. Métodos Selecionou-se 21 pacientes com SP (12 diabetes mellitus, 4 ATTR-FAP e 4 com outras neuropatias), 22 com SM (22 hanseníases) e 26 com SN (13 imunomediadas, 10 idiopáticas e 3 com outras neuronopatias), de acordo com critérios clínicos, etiológicos e eletrofisiológicos. Para cada indivíduo, foi aferida a altura e foram aplicados 20 estímulos distais supramáximos nos nervos mediano, ulnar, fibular e tibial, bilateralmente, para registrar as ondas-F. Uma comparação foi feita, por grupo, das latências (mínimas e médias) e persistências pelos testes Kruskal-Wallis e Bonferroni. Valores de p < 0.05 foram considerados estatisticamente significativos. Resultados Todos os grupos foram pareados por idade, sexo e altura. Não houve diferença estatística significativa entre os grupos quanto às latências das ondas-F. A persistência da onda-F foi capaz de estratificar os grupos, sendo as dos nervos fibulares bilateralmente maiores no grupo SN que nos grupos SM e SP (p < 0.05). Adicionalmente, a persistência das ondas-F dos nervos ulnares e tibiais também foi útil para distinguir SN de SP (p < 0.05). Conclusão A persistência das ondas-F dos nervos fibulares pode ser uma ferramenta adicional e útil para diferenciar síndromes sensitivas periféricas.

SPTLC2 gene mutation leads to intermediate Charcot-Marries-Tooth disease: a family report / 中华神经科杂志

Objective:To report a SPTLC2 gene mutation in a family with a phenotype of Charcot-Marie-Tooth disease.Methods:To screen the family of patients with pathogenic mutations of SPTLC2 gene from the database of hereditary peripheral neuropathy in the Department of Neurology, Peking University First Hospital, and to collect their clinical data, peripheral nerve conduction examination, nerve ultrasound examination, pathological examination of the peroneal nerve and whole exome sequencing results of prohand.Results:One family was screened, the proband was a 16-year-old female with 4 years of sensory loss and anhidrosis of both lower limbs and 16 months of walking difficulty who admitted to Peking University First Hospital in January 2022. Physical examination showed sensory loss, dry skin and weakness in distal limbs. Her father had numbness and dry skin in the distal lower limbs from childhood,weakness and atrophy of his lower limbs in adulthood. He died at age of 52 years old. The nerve conduction study revealed no action potentials of the sensory and motor nerves of the lower limbs in the proband. The amplitude of the compound muscle action potential of the motor conduction of the bilateral ulnar nerve and median nerve decreased, and the nerve conduction velocity of the bilateral median nerve were 32 m/s and 24 m/s. Neurosonography showed thickening of peripheral nerves. Sural biopsy revealed severe loss of myelinated and unmyelinated nerve fibers with onion bulbs formation. SPTLC2 gene showed a known heterozygous p.G435V mutation. The lower limb weakness was improved after oral L-serine.Conclusions:SPTLC2 gene mutation can lead to an intermediate Charcot-Marie-Tooth disease phenotype. L-serine can improve the limb weakness.

A case of hereditary sensory and autonomic neuropathy type 4 presenting with chronic trophic ulcers

Hereditary Sensory and Autonomic Neuropathy (HSAN) is a rare group of diseases involving varying degrees of peripheral nervous system. It is classified into five main types. HSAN type 4 is associated with insensitivity to pain and temperature and anihidrosis. The method of this study was to authors present a case report of a 3 year-old boy with Hereditary Sensory and Autonomic Neuropathy Type 4 presenting with chronic ulcers. Conclusions of this study was to HSAN type IV is a rare condition. There is no definitive treatment available presently for this condition.

Erythromelalgia: a cutaneous manifestation of neuropathy?

Abstract: The low prevalence of erythromelalgia, classified as an orphan disease, poses diagnostic and therapeutic difficulties. The aim of this review is to be an update of the specialized bibliography. Erythromelalgia is an infrequent episodic acrosyndrome affecting mainly both lower limbs symmetrically with the classic triad of erythema, warmth and burning pain. Primary erythromelalgia is an autosomal dominant inherited disorder, while secondary is associated with myeloproliferative diseases, among others. In its etiopathogenesis, there are neural and vascular abnormalities that can be combined. The diagnosis is based on exhaustive clinical history and physical examination. Complications are due to changes in the skin barrier function, ischemia and compromise of cutaneous nerves. Because of the complexity of its pathogenesis, erythromelalgia should always be included in the differential diagnosis of conditions that cause chronic pain and/or peripheral edema. The prevention of crisis is based on a strict control of triggers and promotion of preventive measures. Since there is no specific and effective treatment, control should focus on the underlying disease. However, there are numerous topical and systemic therapies that patients can benefit from.

Syndrome in question

Abstract Ross syndrome is a rare disease characterized by peripheral nervous system dysautonomia with selective degeneration of cholinergic fibers. It is composed by the triad of unilateral or bilateral segmental anhidrosis, deep hyporeflexia and Holmes-Adie's tonic pupil. The presence of compensatory sweating is frequent, usually the symptom that most afflicts patients. The aspects of the syndrome are put to discussion due to the case of a male patient, caucasian, 47 years old, with clinical onset of 25 years.

Radiological and clinical features of bone and joint disease in patients with congenital insensitivity to pain and anhidrosis / 中华放射学杂志

Objective To investigate the radiological and clinical features of osteoarthrosis in congenital insensitivity to pain with anhidrosis (CIPA).Methods The clinical and radiological features in 8 cases of CIPA diseases were retrospectively analyzed. There were five males and three females,age ranged from 11 to 18 years with a median age of (14±3) years. X-ray plain film findings in eight cases were analyzed for the location, extent and contour of the lesions, surrounding bony sclerosis, as well as joint and soft tissue changes. Results The main clinical presentations were insensitivity to pain, anhydrosis, fever, mental retardation and infection. In these eight cases, a total of 166 pieces of bone were involved, including the plantar and phalanges (n=115),phalanx (n=29).The radiological findings include dissolution of the entire bone or most of the bone (n=113), dissolution of a few small areas of the bone (n=40), dissolution of the bone with only residual punctate areas (n=7), the“pushpin sign”and“pencil tip sign”and“flat cut sign”of the finger osteolysis (n=6), sclerosis of peripheral bone (n=12), pathological fractures (n=2). Joint dislocation (n=3),joint deformity (n=3), and Charcot joint (n=3) were observed.Necrosis of soft tissue(n=4), complete absence of soft tissue in the finger or toe (n=4), dot-like calcification of the soft tissue(n=3) were also observed. Conclusion Osteoarthrosis in patients with CIPA had certain X-ray and clinical characteristic findings, which could facilitate its diagnosis.

Two Novel Mutations in the HSN2 Gene Identified in a Korean Patients with Hereditary Sensory Autonomic Neuropathy Type II

A 38-year-old Korean man was diagnosed with hereditary sensory and autonomic neuropathy (HSAN) type 2 because of his chronic sensory neuropathy and progressive acro-mutilation. Genetic analysis revealed that he was a compound heterozygous for two novel mutations in the HSN2 gene including a nonsense mutation (Gln73X) and a 1-bp insertion mutation (Asp379fsX1). To our knowledge, this is the first report of a genetically confirmed case of HSAN type 2 in the Asian population and supports the genetic homogeneity of this rare disease.