F-waves persistence in peripheral sensory syndromes.

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.

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.

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.

Neurophysiological assessment of brachioradial pruritus patients.

BACKGROUND: Pruritus is a common complaint in dermatology. Wartenberg, in 1943, associated pruritus with neuropathy, relating it to the "posterior antebrachial cutaneous nerve neuropathy". In 1968, Waisman described patients with frequent pruritus complaints in the upper limb during the summer, which he named "brachioradial summer pruritus". Currently, this pruritus is named brachioradial pruritus (BRP). BRP is characterized by a chronic pruritus, usually localized, with a long duration, and without apparent cutaneous abnormalities. Neurological disorders both from the central and peripheral nervous systems, including multiple sclerosis, are associated with pruritus. OBJECTIVE: To investigate correlations between symptomatic dermatomes and alterations in the myotomes, as evidenced by electroneuromyography (ENMG). METHODS: Forty-six patients with BRP dermatological diagnoses were subjected to upper limb ENMG. RESULTS: Among 46 patients with C5 to C8 dermatomal pruritus, we evaluated 113 symptomatic dermatomal areas. Overall, 39 (85%) patients had radicular involvement and 28 (60%) had agreement between complaint and the ENMG findings (p=0.015). A total of 80% of the patients with complaints at C7 and 47% at C6 had radicular involvement at the same level. CONCLUSIONS: Among the patients who presented complaints, 47 and 80%, respectively, had ENMG alterations in the C6 and C7 myotomes. We conclude that peripheral nervous system involvement is associated with BRP.

Neurophysiological assessment of brachioradial pruritus patients / Avaliação neurofisiológica de pacientes com prurido braquiorradial

Abstract Background: Pruritus is a common complaint in dermatology. Wartenberg, in 1943, associated pruritus with neuropathy, relating it to the "posterior antebrachial cutaneous nerve neuropathy". In 1968, Waisman described patients with frequent pruritus complaints in the upper limb during the summer, which he named "brachioradial summer pruritus". Currently, this pruritus is named brachioradial pruritus (BRP). BRP is characterized by a chronic pruritus, usually localized, with a long duration, and without apparent cutaneous abnormalities. Neurological disorders both from the central and peripheral nervous systems, including multiple sclerosis, are associated with pruritus. Objective: To investigate correlations between symptomatic dermatomes and alterations in the myotomes, as evidenced by electroneuromyography (ENMG). Methods: Forty-six patients with BRP dermatological diagnoses were subjected to upper limb ENMG. Results: Among 46 patients with C5 to C8 dermatomal pruritus, we evaluated 113 symptomatic dermatomal areas. Overall, 39 (85%) patients had radicular involvement and 28 (60%) had agreement between complaint and the ENMG findings (p=0.015). A total of 80% of the patients with complaints at C7 and 47% at C6 had radicular involvement at the same level. Conclusions: Among the patients who presented complaints, 47 and 80%, respectively, had ENMG alterations in the C6 and C7 myotomes. We conclude that peripheral nervous system involvement is associated with BRP.

RESUMO Antecedentes: O prurido constitui queixa frequente e desafiadora na prática dermatológica. O primeiro estudo a relacionar prurido com neuropatia foi de Wartenberg, em 1943, que associou à "neuropatia do nervo cutâneo antebraquial posterior". Em 1968, Waisman descreveu pacientes com queixas recorrentes de prurido em membros superiores no verão, sendo denominado, então, "brachioradial summer pruritus". Atualmente, esse prurido é denominado como prurido braquiorradial (PBR). O PBR é caracterizado por prurido crônico, geralmente bem localizado, de longa duração e sem anormalidades cutâneas aparentes. Doenças neurológicas, tanto centrais, esclerose múltipla ou acidente vascular cerebral como do sistema nervoso periférico, estão associadas a prurido. Objetivo: Investigar os dermátomos sintomáticos pela eletroneuromiografia (ENMG). Métodos: Foram estudados 46 pacientes com diagnóstico dermatológico de PBR com a eletroneuromiografia dos membros superiores. Resultado: Foram avaliados 46 pacientes com queixa dermatológica de C5 a C8 somando 113 áreas dermatoméricas sintomáticas. Observou-se que 39 (85%) pacientes apresentavam comprometimento radicular, sendo que em 28 (60%) houve concordância plena entre as queixas e os achados da ENMG (p=0,015), e que 80% dos pacientes com queixa em território de C7 e 47% em C6 apresentavam comprometimento radicular no mesmo nível. Conclusões: As queixas mais frequentes foram as correspondentes aos territórios de C6 e C7, sendo que 47 e 80%, respectivamente, apresentaram alteração na ENMG nesses miótomos. Dessa forma, evidenciou-se correlação entre comprometimento do sistema nervoso periférico (i.e., radicular) com PBR.

Clinical-Radiologic Dissociation in Post-traumatic Syringomyelia.

Post-traumatic syringomyelia develops years to decades after spinal trauma in up to 28% of patients. We report a case of a man who developed extensive syringomyelia 14 years after spinal trauma, but had only minimal symptoms. Presumed pathophysiology of this condition and options for surgical management are briefly reviewed.

Comparison between nerve conduction study anf high-resolution ultrasonography with color doppler in type 1 and type 2 leprosy

Objective: To analyze the role of high-resolution ultrasonography with color Doppler (HRUS with CD) to diagnose inflammatory activity (IA) in nerves of leprosy patients under type 1 (RT1) and 2 (RT2) reactions compared to Nerve Conduction Studies (NCS). Methods: Leprosy patients with signs or symptoms suggestive of neuritis (RT1 and RT2) without corticosteroids use were selected. They were evaluated by NCS and subsequently by HRUS with CD. Subacute segmental demyelination and the presence of blood flow, respectively, were considered signs of IA. The two methods were compared for their ability to diagnose patients with leprosy reactions. Results: A total of 257 nerves from 35 patients were evaluated. NCS and HRUS with CD diagnosed IA in 68% and 74% of patients, respectively. When both methods were used concomitantly, the diagnosis rate was 91.4%. HRUS with CD was particular helpful when there was minimal neurophysiological compromise in NCS or when motor potentials were not detected. Conclusion: HRUS with CD was able to detect leprosy reactions, especially when combined with NCS. It was especially useful in two opposite situations: nerves with only minor changes and those without motor response in NCS. Significance: Our data shows the usefulness of HRUS and CD, similar to NCS, as a tool to diagnose leprosy reactions.