Hereditary Neuropathy With Liability To Pressure Palsies:A Case Report And Literature Review

Background:Hereditary neuropathy with liability to pressure palsies(HNPP)is a rare peripheral neuropathy,and is an autosomal dominant disease.The peripheral nerve of the patient is liable to be subjected to trauma or external pressure,which induces paralysis of the peripheral motor nerve and peripheral sensory nerve.Patients often have recurrent,paroxysmal limb weakness or numbness.Since there is no cure for this disease at present,early diagnosis and early prevention are essential to reduce the recurrence of the disease.Objective:A case of hereditary neuropathy with liability to pressure palsies is reported in this article.According to the etiology,pathogenesis,clinical manifestations,electrophysiological characteristics,pathological features,neuroimaging findings,molecular biology characteristics,clinical diagnosis,differential diagnosis,clinical treatment and prognosis,this article will discuss and analyze based on the published literatures.The aim is to improve the level of clinicians' understanding of the disease,so as to facilitate the early diagnosis of this disease and make the two level prevention,so as to effectively improve the clinical prognosis of patients.Methods:A report of the clinical data of a case of hereditary neuropathy with liability to pressure palsies admitted to the Jinan Central Hospital affiliated to Shandong University was reported.A retrospective study of the patient's medical history,physical examination results,.auxiliary examination results,disease diagnosis,differential diagnosis,treatment,and clinical outcomes were reviewed.With reference to the domestic and foreign literature of HNPP,the article summarized the disease.Results:The young male,past body health,was admitted to hospital for one week of numbness and weakness of the left foot.One week before the patient was squatting for half an hour,the left foot appeared numbness and weakness,numbness in the inside of the dorsum of the left foot was significant,the dorsiflexion of the left foot was obviously limited.The results of physical examination showed that the proximal muscle strength of the left lower extremities was 5,the muscle strength of the dorsiflexion of the left foot was 2+,the superficial feeling of the medial region of the left foot's dorsum was diminished,the reflex of the tendons of the lower extremities was weakened.The results of the electrophysiological examination after admission to hospital showed that the motor nerve conduction velocity and sensory nerve conduction velocity of the extremities had varying degrees of slowing down,nerve conduction velocity in the easily compressed parts decreased more obviously,the occurrence of distal motion latency(DML)extend in the easily compressed parts.The patient's father's electrophysiological examination suggested a similar manifestation.The results of patient gene detection suggested a heterozygous deletion mutation of the PMP22 gene.The diagnosis was considered to be hereditary neuropathy with liability to pressure palsies(HNPP).The treatment was given to the patient with nourishment of nerve cell metabolism,improvement of circulation and nerve rehabilitation.The clinical symptoms of the patient were obviously improved after treatment.After being discharged from hospital the patient was advised to avoid nerve compression and limit the excessive force of the limb especially in the clamping part(wrist,elbow,small fibula),the patient was told to pay attention to rest,and the patient was told to avoid fatigue and cold.The patient continued to take oral B vitamins after being discharged from hospital.Conclusion:Hereditary neuropathy with liability to pressure palsies(HNPP)is a rare peripheral neuropathy.The peripheral nerve of the patient is liable to be subjected to trauma or external pressure,which induces paralysis of the peripheral motor nerve and peripheral sensory nerve.A comprehensive and detailed electrophysiological examination is an important method for the diagnosis of HNPP,further electrophysiological examination is necessary when extensive nerve conduction velocity is slowed and extensive distal motion latency(DML)is prolonged.The examination of the median nerve,ulnar nerve and the general peroneal nerve is the key point.The region of HNPP's pathogenicity gene(PMP22 gene)is located in chromosome 17p11.2.Due to the deletion of large fragment DNA of the gene,the expression of peripheral myelin protein 22(PMP22)encoded by the gene is reduced in myelinated sheath of peripheral nerve myelinated fibers.Genetic diagnosis is beneficial to the further diagnosis of HNPP.The pathology of the neuromuscular biopsy showed that the myelin sheath of the peripheral nerve was the sausage like structure,the segmental demyelination and the formation of the newborn myelin sheath.Neuro pathogenesis and neuroimaging examination(MRI and neuroultrasound)can play a role in the diagnosis of HNPP.HNPP should be highly suspected when the clinical manifestation and electrophysiological characteristics of the patients meet the characteristics of HNPP.HNPP should be highly suspected when the clinical manifestation and electrophysiological characteristics of the patients meet the characteristics of HNPP.In the case of the above case,HNPP can be confirmed when the result of gene diagnosis is positive.At present there is no effective cure for HNPP.Early diagnosis,timely symptomatic support and avoidance of traumatic stress and compression are crucial to the prognosis of HNPP patients.