Clinical and neurophysiological features of the hereditary neuropathy with liability to pressure palsy due to the 17p11. 2 deletion / Aspectos clínicos e neurofisiológicos de pacientes com a neuropatia hereditária com a susceptibilidade à pressão associada à deleção 17p11. 2

ABSTRACT The hereditary neuropathy with liability to pressure palsies (HNPP) is an autossomal dominant disorder manifesting recurrent mononeuropathies. Objective Evaluate its clinical and nerve conduction studies (NCS) characteristics, searching for diagnostic particularities. Method We reviewed the neurological manifestations of 39 and the NCS of 33 patients. Results Family history was absent in 16/39 (41%). The onset complaints were weakness in 24, pain in 6, sensory deficit in 5 and paresthesias in 4. Pain was seen in 3 other patients. The following neuropathy patterns were found: multiple mononeuropathy (26), mononeuropathy (7), chronic sensorimotor polyneuropathy (4), chronic sensory polyneuropathy (1) and unilateral brachial plexopathy (1). NCS showed a sensorimotor neuropathy with focal conduction slowing in 31, two had mononeuropathy and another brachial plexopathy. Conclusion HNPP presentation is variable and may include pain. The most frequent pattern is of an asymmetrical sensory and motor neuropathy with focal slowing at specific topographies on NCS.

RESUMO A neuropatia hereditária com susceptibilidade à pressão (HNPP) é uma doença autossômica dominante que manifesta mononeuropatias recorrentes. Objetivo Avaliar as características clínicas e os estudos da condução nervosa (ECN) procurando particularidades diagnósticas. Método Revisamos as características clínicas de 39 e os ECN de 33 pacientes. Resultados História familiar ausente em 16/39 (41%). As manifestações iniciais foram: fraqueza em 24, dor em 6, déficit sensitivo em 5 e parestesias em 4. Dor foi referida por outros 3 pacientes. Os seguintes padrões de neuropatia foram observados: mononeuropatia múltipla (26), mononeuropatia (6), polineuropatia sensitivo-motora (4), polineuropatia sensitiva (1) e plexopatia braquial unilateral (1). Os ECN mostraram uma neuropatia sensitivo-motora com redução focal da velocidade de condução em 31, dois tinham mononeuropatia e outro plexopatia braquial. Conclusão A apresentação da HNPP é variável e pode incluir dor. O padrão mais frequente é o de uma neuropatia sensitivo-motora assimétrica com alentecimentos focais da condução em topografias específicas nos ECN.

Clinical, electromyography and genetic features of hereditary neuropathy with liability to pressure palsies phenotype in children (report of 1 case) / 临床神经病学杂志

Objective To explore the clinical , EMG and genetic characteristics of children with hereditary neuropathy with liability to pressure palsies phenotype (HNPP).Methods One case of HNPP diagnosed by gene were reported, and combined with the literature , the clinical, electromyography and genetic characteristics were summarized.Results Female patient, 11 years and 8 months, left foot could not be dorsal flexion and numbness appeared after the movement in 10 d before admission ,EMG showed multiple peripheral nerve injury .Patient's father and uncle were very similar to the history .Genetic examination showed 1363.2 kb heterozygous deletion on the chr17:14095421 -15458636, and the diagnosis was HNPP .Conclusions When limb weakness happened in children after slight stretch or compression , perform EMG examination as early as possible .Children with extensive peripheral nerve damage , limited limb paralysis , and a similar family history , should pay attention to HNPP , and gene examination should be given .

Sonographic Evaluation of the Peripheral Nerves in Hereditary Neuropathy With Liability to Pressure Palsies: A Case Report

Hereditary neuropathy with liability to pressure palsies (HNPP) is an autosomal dominantly inherited disorder that affects peripheral nerves by repeated focal pressure. HNPP can be diagnosed by clinical findings, electrodiagnostic studies, histopathological features, and genetic analysis. Ultrasonography is increasingly used for the diagnosis of neuromuscular diseases; however, sonographic features of HNPP have not been clearly defined. We report the sonographic findings and comparative electrodiagnostic data in a 73-year-old woman with HNPP, confirmed by genetic analysis. The cross-sectional areas of peripheral nerves were enlarged at typical nerve entrapment sites, but enlargement at non-entrapment sites was uncommon. These sonographic features may be helpful for diagnosis of HNPP when electrodiagnostic studies are suspicious of HNPP and/or gene study is not compatible.

Neurophysiological diagnosis of hereditary neuropathy with liability to pressure palsies / 第二军医大学学报

Objective: To explore the neurophysiological properties of hereditary neuropathy with liability to pressure palsies (HNPP), so as to provide evidence for the diagnosis of HNPP. Methods: Three families (8 individuals) with clinically affected and asymptomatic HNPP patients underwent routine electrodiagnostic tests, including median, ulnar, radial, tibial and proneal motor and sensory nerve conduction, and the results: were compared with those of 30 healthy subjects. Results (1) Prolongation of the distal nerve conduction latencies was the most seen abnormality (92.1%), mainly found in the median and common peroneal nerves, including those with and without symptoms. (2) The rate of motor nerve conduction slowing was 63.2%, mostly seen in the median and common peroneal nerves. (3)The rate of sensory nerve conduction slowing was 89.6%, mostly affecting the sural and median nerves. (4)The conduction block of the ulnar nerve at the elbow was more commonly seen than that of the proneal nerve at the fibular head. Conclusion: Neurophysiological examination is a noninvasive, fast, simple and accurate diagnosis way for clinically suspected HNPP patients, and it can be used for screening the family members of HNPP patients and for prevention of HNPP.

Clinical, Electrophysiological and Pathological Characteristics in Hereditary Neuropathy with Liability to Pressure Palsies (HNPP) with Chromosome 17p11.2-p12 Deletion

BACKGROUND: Hereditary neuropathy with liability to pressure palsies (HNPP) is a peripheral nerve disorder characterized by autosomal dominant inheritance, recurrent pressure palsies, reduced motor and sensory conduction velocities and sausage-like swellings (tomacula) of myelin sheaths in nerve biopsy. A 1.5-Mb deletion in chromosome 17p11.2- p12 is present in the majority but not all cases of HNPP. The aim of the present study was to evaluate the clinical, electrophysiological and morphological aspects of HNPP patients associated with chromosome 17p11.2-p12 deletion. METHODS: To detect the presence of the deletion, the DNA of the patients was analyzed with pVAW409R3 (D17S122). An electrophysiological study was done in all patients. Sural nerve biopsy with teasing was done in three patients. RESULTS: DNA analysis and electrophysiological tests revealed the deletion in 8 families and 16 patients. Nerve conduction studies demonstrated diffuse mild to moderate slowing of nerve conduction velocities especially worse over the common entrapment sites, regardless of clinical manifestations. The long duration of compound muscle and nerve action potentials without conduction blocks or dispersion is characteristic of patients with HNPP. The tomacula of myelin sheaths was found on sural nerve teasing. CONCLUSIONS: We report the clinical, electrophysiological and morphological aspects of the Korean HNPP patients associated with chromosome 17p11.2-p12 deletion. (J Korean Neurol Assoc 19(3):251~259, 2001)

Intraoperative Electrophysiological Monitoring during Microvascular Decompression for Hemifacial Spasm and Surgical Outcome

BACKGROUND: Hereditary neuropathy with liability to pressure palsies (HNPP) is a peripheral nerve disorder characterized by autosomal dominant inheritance, recurrent pressure palsies, reduced motor and sensory conduction velocities and sausage-like swellings (tomacula) of myelin sheaths in nerve biopsy. A 1.5-Mb deletion in chromosome 17p11.2- p12 is present in the majority but not all cases of HNPP. The aim of the present study was to evaluate the clinical, electrophysiological and morphological aspects of HNPP patients associated with chromosome 17p11.2-p12 deletion. METHODS: To detect the presence of the deletion, the DNA of the patients was analyzed with pVAW409R3 (D17S122). An electrophysiological study was done in all patients. Sural nerve biopsy with teasing was done in three patients. RESULTS: DNA analysis and electrophysiological tests revealed the deletion in 8 families and 16 patients. Nerve conduction studies demonstrated diffuse mild to moderate slowing of nerve conduction velocities especially worse over the common entrapment sites, regardless of clinical manifestations. The long duration of compound muscle and nerve action potentials without conduction blocks or dispersion is characteristic of patients with HNPP. The tomacula of myelin sheaths was found on sural nerve teasing. CONCLUSIONS: We report the clinical, electrophysiological and morphological aspects of the Korean HNPP patients associated with chromosome 17p11.2-p12 deletion. (J Korean Neurol Assoc 19(3):251~259, 2001)