中毒性周围神经病ToxicNeuropathies:Drugs,Metals,andorganiccompounds临床和组织学共同特征毒素影响轴索早于许旺氏细胞;毒素通常首先累及大有髓纤维轴索,且大有髓纤维受损最严重;发病率和周围神经病严重程度与毒素接触剂量、时间相关联;身体最长的轴索是至足趾的感觉纤维,大多数中毒性神经病首发症状为足远端感觉障碍,且主要为大纤维,如振动觉常是早期客观发现。工业或环境重金属毒素引起的临床综合症周围神经病:砷主要引起感觉神经病,无机铅引起运动神经病,有机磷化合物和铊引起混合性神经病;脑病:铅中毒引起共济失调、偏瘫、视神经萎缩;视神经炎:砷中毒引起短暂或永久性视力损害,铊中毒引起视物模糊、视野缺损;小脑功能障碍:有机汞出现共济失调帕金森综合症:锰中毒出现锥体外系征:面具脸和肌僵直;智能衰退:有机铅、汞出现精神异常、精神病砷中毒神经系统损害毒物来源:采矿、饮高砷水、中药(雄黄)、燃煤、海产品等;无机砷代谢:肝脏大量中毒:早期胃肠道症状:恶心呕吐,胃肠激惹;自主神经症状:心动过速,低血压。10~20天后出现周围神经病:感觉神经(大纤维)受累为主,远端麻木或感觉异常,病理学:远端轴索丢失/伴脱髓鞘长期低水平砷接触(3阶段)FirststageChronicabsorption500-1000μg/dMalaise;Anorexia;Vomiting2ndstageMembraneirritationHyperkeratosisofFeet&Hands;Dark(Gray)skin;HypopigmentationWhitestria(Meeslines)AplasticanemiaRenaldamagePolyneuropathySensoryloss:Stocking-glove;LargeSmallfiberWeakness:MildCSF:ProteinmildlyincreasedPathology:Axonalloss;DistalRecovery:BetterinmildlyaffectedLongterm:Carcinogen,Lung,skin,liver,kidney,&bladderDiagnosis:ArseniclevelsAcute(6weeks):UrineChronicTissues:Hair(Pubic);FingernailsLevel:1μg/g铅中毒神经病ToxicSources:Occupational:Smelting;Batterymanufacture;Demolition;AutoradiatorIngestion:Paint;wineprocessedinleadvessles;chinesemedicines.BodystorageRapidturnoverpool:Blood(95%inRBCs)&organs;1/2lifeof1to20daysSlowturnoverpool:Bones;1/2lifeof7to20years;95%ofbodyleadburden神经系统临床表现急性中毒:周围神经损害,中毒性脑病慢性中毒:神经症综合症:见于早期,头晕、头痛、无力、肌肉关节酸痛、多汗、失眠等;周围神经病:运动神经损害,伸肌麻痹出现典型的垂腕(铅手)、垂踝(双腓总神经麻痹),肱型及肩胛-肱型麻痹;进行性肌萎缩:局限性,以手部肌肉萎缩及震颤多见;中毒性脑病:癫痫样发作、类精神分裂症、类麻痹样痴呆、震颤麻痹、共济失调等系统损害表现“铅线”、“铅容”口内金属味,恶心呕吐腹泻或便秘,腹绞痛肝肾功能损害月经不调高血压实验室检查周围血检查:点彩红细胞每百万红细胞超过300个、网织红细胞超过1.0%;尿铅增高(正常上限0.08mg/L)Basophilicstipplingoferythrocytes汞中毒神经损害毒物来源:汞蒸气(淘金)吸入、中药偏方(轻粉:甘汞Hg2Cl2)、水和食物污染(甲基汞)亚急性无机汞中毒主要引起口腔炎及肾脏损害;有机汞中毒引起神经损害。Subacute:MetallicmercuryvaporNeuropathyMotorAxonalMyokymiaEncephalopathyOther:Mouthinflammation;GI;FetidbreathChronicCNS:Encephalopathy;Psychosis;Extrapyramidal;AtaxiaNeuropathy:Sensory&Motor;Pain&paresthesiasChildren:AcrodyniaEncephalopathyAutonomic:Tachycardia;Hypertension;SweatingontrunkInsomnia;Weightloss;Constipation慢性锰中毒神经系统损害毒物来源:电焊工,机械制造业,空气中锰浓度超标诊断依据国际GB-3232-82《职业性慢性锰中毒诊断标准及处理原则》临床表现中毒性精神异常:类神经症,焦虑、忧郁症;帕金森综合症:构音障碍震颤(actiontremor)四肢肌张力增高(rigidity)行走困难、步态异常腱反射亢进/病理征性功能障碍苯妥英钠(Phenytoin)中毒Anti-epileptic:Blocksvoltage-gatedNa+channelsNeuropathySensory:Mild;Symmetric;DistallegsMaximumdisability:MinorIncidence:HighwithchronicusageElectrophysiology:AxonallossPathology:AxonallossAtaxia;Gingivalhyperplasia;HypertrichosisOrganophosphatecompounds有机磷中毒迟发性神经病Toxicsource:Insecticides,Petroleumadditives,Flameretardants,SuicideExposure:Absorbedthroughskin,respiratory,GItract有机磷中毒迟发性神经病OnsetParesthesias&MusclecrampsDelayed7to12daysfollowingsingleexposureMotor&sensoryDistalPathology:Axonalloss,Distalregionsoflongaxons,PNS&CNSMyelopathy:SpasticparaparasisPrognosisNeuropathy:SlowimprovementovertimeMyelopathy:Littleornoimprovament酒精中毒相关性神经损害Wernicke脑病和Korsakoff精神病小脑变性Marchiafara-Bignami病桥脑中央髓鞘溶解症周围神经病肌病肝性脑病和获得性肝脑变性胎儿酒精综合症