兒科學之小兒貧血

兒科學之小兒貧血TeachingpurposeTounderstandfeaturesofhematopoiesisandbloodinchildren.Tocomprehendclinicalfeatures,diagnosisandtherapyofanemia.Tounderstandthedefinition,gradedivisionandclassificationofanemiainchildren.Tomasteretiology,pathogenosis,diagnosis,therapyandpreventionofnutritionalirondeficiencyanemiaandnutritionalmegaloblasticanemia.2020/11/32Featuresofhematopoiesisinchildren

Hematopoiesisinfetalperiod（胎兒期造血）

Developmentalhematopoiesisoccursinthreeanatomicstages—mesoblastic（中胚層）,hepatic（肝）,andmyeloid（骨髓）.

2020/11/33Fig.Hematopoiesisinfetalperiodyolksac

liverspleenBonemarrowlymphnode2020/11/34FeaturesofhematopoiesisinchildrenHematopoiesisafterbirth

Hematopoesisinbonemarrow

Extramedullaryhemopoiesis

（骨髓外造血）2020/11/35Hematopoesisinbonemarrow

Yellowbonemarrow（黃骨髓）cancomebacktoredbonemarrow（紅骨髓）whenhematopoeticneedincreases.Yellowbonemarrowisdeficiencyinchildren,especiallyininfantandtoddlerperiod.

2020/11/36

Whenhematopoieticdemandincreases,liver,spleenandlymphnodescomebacktotheStatustoproducebloodcells,hepatomegaly（肝腫大）andsplenomegaly（脾腫大）appears,andmaybethereareimmatureerythrocytesandgranulocytesincirculatingblood.Extramedullaryhemopoiesisisthespecificphenomenaonlyappearingininfantandtoddler.

Extramedullaryhemopoiesis（髓外造血）2020/11/37Featuresofbloodinchildren2020/11/38Erythrocyteandhemoglobin

7654321012h10d

3m6m1yRBC(×1012/L)Years2020/11/39Hemoglobin

Atbirth1yr2yr2020/11/310LeucocytecountWBC×109/L9h10d1y8y1232020/11/311%2040608005d5yDifferentialcountofWBC(白細胞分類計數(shù))Lymphocyte淋巴細胞Granulocyte粒細胞2020/11/312MorphologicalclassificationofanemiaTypesMCV（fl）MCH(pg)MCHC(%)Normal80～9428～3232～38macrocytic

（大細胞性）>94>3232～38normocytic

（正細胞性）80～9428～3232～38microcytic

（小細胞性）<80<2832～38hypochromicmicrocytic

（小細胞低色素性）<80<28<322020/11/313

Bloodroutine

HypochromicmicrocyticMacrocyticNormocytic

（Hb↓＞RBC↓）（Hb↓＜RBC↓)（Hb↓=RBC↓）IDA

（缺鐵性貧血）

megaloblasticacutebleedingThalassemiaVitB12↓↓

hemolyticanemiasideroblasticanemiafolicacid↓aplasticanemiaChronicinfectionmostofsecondaryanemia

2020/11/314AgeHbconcentration(g/L)<28d<1451～4mon<904～6mon<1006mon～6y<1106～14y<120Thecriterionofanemia.

2020/11/315Nutritionalirondeficiencyanemia(IDA)

營養(yǎng)性缺鐵性貧血2020/11/316

Zhou,male,10monthsold.Palenessinfaceandlipsfor4mons.Hisfacialexpressionbecamemoreandmorepalesince6monthsofage.Withoutfeverandbleeding.Hewasprematurebirthat33weeksofgestationalageandfedwithMother'smilkonly.

Case12020/11/317PE:Pallor.nojaundiceandhemorrhagicspotsinskinandsclera;Bilateralsubmandibularlymphnodesare0.8×0.8cm.Breathsoundsinlungsaredistinct;therearenorhonchiandmoistrale.HR100/min.ThereisII/VIsystolicmurmurinprecordialregion.Theliverandspleenenlargeto4cmand3cmbelowlowercostamarginrespectively.Case12020/11/318BloodroutinetestWBC4.0109/LLym2.4(60%)109/LGran1.6(40%)109/LRBC2.181012/LHb47g/LMCV70.4flMCH22.4pgMCHC176g/LRDW23.7%RC0.026Plt194109/L2020/11/319questionsDoananemiaexistWhichkindofanemiadoesitbelong2020/11/320answerHypochromicmicrocyticanemia(小細胞低色素性貧血）

2020/11/321questionsWhatisthecauseofanemiainthecaseabove2020/11/322answer

ThecauseofanemiainthecaseaboveisdeficiencyofironbecauseheisprematureandisfedwithMother'smilkonly.2020/11/323etiology

Theetiologicalfactorsofnutritionalirondeficiencyanemia:

Storedirondeficiencyatbirth.Inadequatediet.Rapidlygrowth.Malabsorption.Excessivelossofiron.2020/11/324questionsNextexaminations2020/11/325SmearofBloodnormalThepatient’2020/11/326Bonemarrow2020/11/327Bonemarrowexamination

Thebonemarrowishypercellular,witherythroidhyperplasia（過度增生）.Thenormoblasts(幼紅細胞)mayhavescanty,fragmentedcytoplasmwithpoorhemoglobinization.Leukocytesandmegakaryocytesarenormal.HemosidenincannotbedemonstratedinmarrowspecimensbyPrussianbluestaining.2020/11/328questionsHowdoirondeficiencycauseanemia2020/11/329questions

Pathogenesisofnutritionalirondeficiencyanemia.2020/11/330

鐵缺乏

貯存鐵血清鐵血紅蛋白鐵↓酶鐵↓

紅細胞內(nèi)Ｈｂ合成↓↓含鐵酶↓細胞分裂不受影響鐵依賴酶↓

Ｈｂ↓↓，RBC正常或↓某些細胞功能紊亂，如生物氧化、細胞呼吸小細胞低色素性貧血神經(jīng)遞質(zhì)分解與合成等

血液系統(tǒng)癥狀非血液系統(tǒng)癥狀一般貧血表現(xiàn)行為發(fā)育異常髓外造血表現(xiàn)皮膚粘膜損害心血管系統(tǒng)癥狀細胞免疫功能↓缺鐵性貧血發(fā)病機理2020/11/331

IronstudyIronstudyIDIDEIDA*serumferritin(SF)↓↓↓↓↓Ironstore↓↓↓↓↓FEP(紅細胞游離原卟啉）N↑↑↑sideroblastsN↓↓↓SerumironNNor↓↓↓2020/11/332Therapy

goodnursingremovalofetiologicalfactors

treatmentwithironpreparation

2020/11/333Oraladministrationofsimpleferroussaltsferroussulfateferrousgluconateferrorsfumaratepolysaccharideiron

Dosage:4-6mg/kgelementalironperday

Oralironpreparation2020/11/334

Administrationtheironpriortomeals

Administrationascorbicacidwithironpreparation.

Therapeuticcourse:withdrawalofironpreparation6-8weeksafterhemoglobinrecovertonormallevelorwhenSFandFEPisnormal.

Oralironpreparation2020/11/335ParenteralironTobeadministeredonlyforgastrointestinalmalabsorptionorsevereintolerancepreventseffectiveoralirontherapy.2020/11/336Reticulocytosis2020/11/337Transfusion2020/11/338Prevention2020/11/339NutritionalMegaloblasticAnemia

（營養(yǎng)性巨幼細胞性貧血）

FolicacidandvitaminB12deficiencyareprimarycausesofmegaloblasticanemia.2020/11/340Case2.

Zhou,male,8gressivedrowsinessandgoasleepfor20hrpreday.Hecannotsmileandtoraisehishead,whichcanbedonebefore.HewasfedwithMother'smilkonly.2020/11/341Case2.

PE:emotionalexpressionSluggishness（呆滯）,Pallor.nojaundice,rashesandhemorrhagicspotsinskin;pallorinhislips.Breathsoundsaredistinctandtherearenoraleinlungs.Heartrateis110timesperminute.Theliverandspleenenlargeto3centimetersand4centimetersbelowlowercostamarginrespectively.2020/11/342BloodroutineBeforeAfternormallevelsWBC3.18.6(4.0～10.0)109/LLYM83.066.0(50～70)%GRAN17.032(30～50)%RBC1.982.93(3.5～5.5)1012/LHb6979(110～160)g/LMCV103.388.0(82～92)flMCH34.827.0(27～34)pgMCHC337307(320～360)g/LRDW19.420.9(11.5～14.5)%RC0.0180.090(0.005～0.015)PLT80644(100～300)109/L2020/11/343questions:1.Whichkindofanemiaitbelongs2020/11/344AnswerTheclinicdatashowsamacrocyticanemia.

2020/11/345Smearofbloodpatientnormal2020/11/346Smearofpatient’blood2020/11/347BM(骨髓)2020/11/348Bonemarrowexamination

Thebonemarrowishypercellularbecauseoferythroidhyperplasia.Megaloblasticchangesareprominent,althoughsomenormalRBCprecursorsmayalsobefound.Large,abnormalneutrophilicforms(giantmetamyelocytes)withcytoplasmicvacuolationareseen,aswellashypersegmentationofthenucleiofmegakaryocytes.2020/11/349questions:2.IsitcausedbydeficiencyoffolicacidorvitaminB122020/11/350Answer

Inthiscase,macrocyticanemiaiscausedbydeficiencyofvitaminB12.Why2020/11/351questions:3.whatisthedifferencesinclinicalmanifestationbetweendeficiencyoffolicacidanddeficiencyofvitaminB122020/11/352葉酸↓四氫葉酸↓核苷酸尤其胸苷合成↓

VitB12↓DNA合成↓RNA合成正常神經(jīng)髓鞘中脂細胞分裂↓蛋白質(zhì),如Hb蛋白合成不足細胞增殖↓合成正常

神經(jīng)纖維功能細胞巨幼變不完整細胞數(shù)量下降

表情呆滯,反應差RBC↓WBC↓PLT↓其它組織發(fā)育落后,常倒退細胞↓肢體震顫可有病理反射

精神神經(jīng)癥狀巨幼細胞性貧血營養(yǎng)性巨幼細胞性貧血發(fā)病機理

2020/11/353Answer

InthemacroblasticanemiaproducedbydeficiencyofvitaminB12,thesymptomsandsignsincludethoseofanemiaandneuropathy.Patientsdevelopademyelinatinglesionofneuronsofthespinalcolumnandcerebralcortex.Thisconditionresultsinparesthesias(感覺異常)ofthehandsandfeet,unsteadinessofgait,andeventuallymemorylossandpersonality（智力）changes.Thereisretardofintellectiveandphysicaldevelopment.Trembling（震顫）ofExtremitiesorhead,hypertensionofmuscle,tendonreflexreinforcement,positiveBabinski'ssignmayappear.

2020/11/354DiagnosisPreliminaryassessmentofmegaloblasticanemia2020/11/355DiagnosisFinaldiagnosis:

TodistinguishthedeficiencyoffolicacidwiththedeficiencyofvitaminB12