溶血性貧血教學(xué)課件-2

1、第六篇 血液系統(tǒng)疾病第六章 溶血性貧血溶血性貧血（HA）概述定義臨床分類臨床表現(xiàn)發(fā)病機(jī)制與實(shí)驗(yàn)室檢查診斷和鑒別診斷治療一、定義溶血是一組由于后天或先天的各種原因使紅細(xì)胞遭破壞壽命縮短的過(guò)程。HA系指紅細(xì)胞破壞超過(guò)骨髓造血代償功能而發(fā)生的一種貧血。如溶血發(fā)生而骨髓能代償時(shí)，臨床無(wú)貧血，稱為溶血性疾病。二、臨床分類紅細(xì)胞自身異常所致的HA紅細(xì)胞外部異常所致的HA （一）紅細(xì)胞自身異常所致的HA紅細(xì)胞膜異常遺傳性紅細(xì)胞酶的缺乏遺傳性珠蛋白生成障礙血紅素異常 紅細(xì)胞膜異常遺傳性紅細(xì)胞膜缺陷 遺傳性球形紅細(xì)胞增多癥、遺傳性橢圓形紅細(xì)胞增多癥、遺傳性棘性細(xì)胞增多癥、遺傳性口形細(xì)胞增多癥獲得性血細(xì)胞膜糖化肌

2、醇磷酯（GPI）錨鏈膜蛋白異常，如PNH 遺傳性紅細(xì)胞酶的缺乏戊糖磷酸途徑酶缺陷 如G6PD缺乏癥等無(wú)氧糖酵解途徑缺陷 如丙酮酸激酶缺乏癥等核苷代謝酶系、氧化還原酶系等缺陷等遺傳性珠蛋白生成障礙珠蛋白肽鏈結(jié)構(gòu)異常不穩(wěn)定血紅蛋白病、血紅蛋白病S、D、E等珠蛋白肽鏈數(shù)量異常地中海貧血血紅素異常先天性紅細(xì)胞卟啉代謝異常如紅細(xì)胞生成性血卟啉病，原卟啉型、尿卟啉型和糞卟啉型鉛中毒可影響血紅素的合成發(fā)生HA（二）紅細(xì)胞外部異常所致的HA 免疫性HA血管性生物因素理化因素免疫性HA自身免疫性HA溫抗體型或冷抗體型（冷凝集型、D-L抗體型）；原發(fā)性或繼發(fā)性（SLE、病毒或藥物等0同種免疫性HA如血型不合的輸血

3、反應(yīng)、新生兒HA血管性微血管病性HA如（TTP/HUS）、DIC、敗血癥等瓣膜?。衡}化性主動(dòng)脈瓣狹窄、人工心瓣膜和血管炎等血管壁受到反復(fù)擠壓：行軍性血紅蛋白尿生物因素、理化因素蛇毒、瘧疾和黑熱病等大面積燒傷、血漿中滲透壓改變和化學(xué)因素如苯肼、亞硝酸鹽等中毒，可引起獲得性高鐵血紅蛋白血癥而溶血（三）臨床表現(xiàn)急性溶血：起病急，突然寒戰(zhàn)、高熱、頭痛、四肢酸痛等，面色蒼白、血紅蛋白尿和黃疸。嚴(yán)重者周圍循環(huán)衰竭和急性腎衰竭慢性溶血：起病慢，常有貧血、黃疸和肝脾腫大三個(gè)特征膽石癥、肝功能損害嚴(yán)重溶血時(shí)骨髓腔擴(kuò)大，X線骨皮質(zhì)變薄、骨骼變形（四）發(fā)病機(jī)制和臨床表現(xiàn)紅細(xì)胞破壞和血紅蛋白降解紅系代償性增生紅細(xì)胞具

4、有缺陷或壽命縮短紅細(xì)胞破壞和血紅蛋白降解血管內(nèi)溶血游離Hb升高（40mg/L）結(jié)合珠蛋白降低（3Primary Laboratory InvestigationThe increased reticulocyte count is usually accompanied by peripheral smear RBC polychromasiaMorphologyPathophysiologyClinical RelevanceRed Blood Cell MorphologyInter-relationship TriadMorphology in HAMorphology specific

5、 to the type of HA may be present, e.g., spherocytes, elliptocytes and stomatocytesSecondary Laboratory InvestigationDecisions about what procedures to use for secondary, or follow-up, investigation are based on the findings of the hemogram and morphologySecondary Laboratory InvestigationChemistryBi

6、lirubin: Increased unconjugated bilirubin is indicative of hemolysisSecondary Laboratory InvestigationChemistry, continuedHaptoglobinCarries free plasma globinDecreased levels are indicative of hemolysisMay be increased in inflammation masking hemolysisSecondary Laboratory InvestigationChemistry, co

7、ntinuedIncreased free plasma hemoglobinIncreased lactic dehydrogenaseUrinalysisHemoglobinuria or methemoglobinuriaHemosiderinuriaUrobilinogenSurvey of HA by TypeHereditaryAcquiredHereditary HAMembrane abnormalitiesEnzymopathiesPlasma constituent abnormalitiesRBC Membrane Structure+PlasmaIntegralProt

8、einsPeripheral ProteinsLipid Bi-LayerLipid Bi-LayerRBC CytoplasmMembrane AbnormalitiesSpherocytosisElliptocytosisPyropoikilocytosisStomatocytosisMembrane AbnormalitiesSee figure 17-1Excess membrane cholesterolRBC inclusionsSenescent RBCComplement coated RBCAntibody coated RBCRigid RBCSpleen: Effects

9、 on RBCsHereditary SpherocytosisDefect: RBC protein defects affecting spectrinPathophysiologyIncreased Na+ permeability RBC rigidity Destruction in spleenTesting: Increased osmotic fragilityIncubated osmotic fragility Hereditary SpherocytosisSee figures 17-2 and 3Spherocyte Morphology & Pathophysiol

10、ogyLacks area of central pallorAdditional causesImmunologic reactionPhysical traumaUsually 6.5 m diameterMicrospherocytes: 25% of all RBCs)Macro-ovalocytes seen in megaloblastic anemiasNon-specific finding in other types of anemia(30 short, blunt projections evenly distributed over the cell surfaceA

11、.K.A. burr cell, crenated RBC & sea urchin cellWet mount comparisonAcanthocyte Morphology5-12 thornlike spicules unevenly distributed over the cell surfaceProjections may be club shaped or drumstick shaped (spur cells)Acquired Hemolytic AnemiaExtracorpuscular defectsAbnormal blood vessel structureMe

12、chanical injuryMiscellaneousIntracorpuscular defectsImmune processesExtracorpuscular DefectsMicroangiopathic hemolytic anemiaDisseminated intravascular coagulation (DIC)Hemolytic uremic syndrome (HUS)Thrombotic thrombocytopenic purpura (TTP)Direction ofblood flowFibrinSchistocyteMicroangiopathic Tra

13、umaSchistocyteMicroangiopathic TraumaSlides not shown.See Figure 8-12, p. 94, Clinical HematologyIntracorpuscular-PNHMajor defect-Complement sensitive RBCs in acidified plasma environmentPathophysiology-Extravascular lysis of affected RBC occurring during the evening hours leading to a chronic hemol

14、ytic anemiaIntracorpuscular-PNHSecondary investigationScreening test-Sugar water test Increased hemolysis in PNHDefinitive test-Hams acidified serum test (See Table 18-1, Clinical Hematology, p. 269.) Significant lysis in tubes containing acidified serum and complementModule Objectives:Blood Loss An

15、emiaAt the end of this module you should be able toDescribe the natural course of acute blood loss anemiaDescribe the changes in laboratory test results that can be expected in acute blood loss anemiaModule Objectives:Blood Loss AnemiaExplain the test results expected in chronic blood loss anemiaLab

16、oratory FindingsBlood Loss AnemiaAcute blood loss anemia No change in CBC parameters in first few hours3-4 hoursHb/Hct Possible WBC count Possible Laboratory FindingsBlood Loss AnemiaAcute blood loss anemia, continued12-24 hoursHb/Hct reflecting degree of blood lossProbable leukocytosisPossible thro

17、mbocytosisLaboratory FindingsBlood Loss AnemiaAcute blood loss anemia, continued3-5 daysPossible MCVPossible reticulocyte countPossible RPI (3)Laboratory FindingsBlood Loss AnemiaSee Table 20-2Laboratory FindingsBlood Loss AnemiaFindings and course in chronic blood loss anemia are similar to iron de

18、ficiency anemiaLaboratory FindingsBlood Loss AnemiaMorphology-Acute blood lossFirst few hours no significant changes3-4 hoursPossible left shiftPossible NRBCsLaboratory FindingsBlood Loss AnemiaMorphology-Acute blood loss, continued12-24 hoursPossible left shiftPossible NRBCsPlatelet estimate Labora

19、tory FindingsBlood Loss AnemiaMorphology-Acute blood loss, continued3-5 daysPossible macrocytosisPossible polychromasiaLaboratory FindingsBlood Loss AnemiaFindings and course in chronic blood loss anemia are similar to iron deficiency anemiaEtiologyAcute Blood Loss AnemiaTraumatic hemorrhageGI hemorrhageOperative hemorrhageRuptured aneurysmsObstetric complicationsMassive hemoptysisEtiology-Chronic Blood Loss AnemiaExcessive mensesGI hemorrhageColon carcinomaHookwormPathophysiology-Chronic Blood Loss AnemiaPathophysiology similar to iron deficiency anemiaA