儿科学之小儿贫血

儿科学之小儿贫血TeachingpurposeTounderstandfeaturesofhematopoiesisandbloodinchildren.Tocomprehendclinicalfeatures,diagnosisandtherapyofanemia.Tounderstandthedefinition,gradedivisionandclassificationofanemiainchildren.Tomasteretiology,pathogenosis,diagnosis,therapyandpreventionofnutritionalirondeficiencyanemiaandnutritionalmegaloblasticanemia.2020/11/32Featuresofhematopoiesisinchildren

Hematopoiesisinfetalperiod（胎儿期造血）

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

2020/11/33Fig.Hematopoiesisinfetalperiodyolksac

liverspleenBonemarrowlymphnode2020/11/34FeaturesofhematopoiesisinchildrenHematopoiesisafterbirth

Hematopoesisinbonemarrow

Extramedullaryhemopoiesis

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

Yellowbonemarrow（黄骨髓）cancomebacktoredbonemarrow（红骨髓）whenhematopoeticneedincreases.Yellowbonemarrowisdeficiencyinchildren,especiallyininfantandtoddlerperiod.

2020/11/36

Whenhematopoieticdemandincreases,liver,spleenandlymphnodescomebacktotheStatustoproducebloodcells,hepatomegaly（肝肿大）andsplenomegaly（脾肿大）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(白细胞分类计数)Lymphocyte淋巴细胞Granulocyte粒细胞2020/11/312MorphologicalclassificationofanemiaTypesMCV（fl）MCH(pg)MCHC(%)Normal80～9428～3232～38macrocytic

（大细胞性）>94>3232～38normocytic

（正细胞性）80～9428～3232～38microcytic

（小细胞性）<80<2832～38hypochromicmicrocytic

（小细胞低色素性）<80<28<322020/11/313

Bloodroutine

HypochromicmicrocyticMacrocyticNormocytic

（Hb↓＞RBC↓）（Hb↓＜RBC↓)（Hb↓=RBC↓）IDA

（缺铁性贫血）

megaloblasticacutebleedingThalassemiaVitB12↓↓

hemolyticanemiasideroblasticanemiafolicacid↓aplasticanemiaChronicinfectionmostofsecondaryanemia

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

2020/11/315Nutritionalirondeficiencyanemia(IDA)

营养性缺铁性贫血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(小细胞低色素性贫血）

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（过度增生）.Thenormoblasts(幼红细胞)mayhavescanty,fragmentedcytoplasmwithpoorhemoglobinization.Leukocytesandmegakaryocytesarenormal.HemosidenincannotbedemonstratedinmarrowspecimensbyPrussianbluestaining.2020/11/328questionsHowdoirondeficiencycauseanemia2020/11/329questions

Pathogenesisofnutritionalirondeficiencyanemia.2020/11/330

铁缺乏

贮存铁血清铁血红蛋白铁↓酶铁↓

红细胞内Ｈｂ合成↓↓含铁酶↓细胞分裂不受影响铁依赖酶↓

Ｈｂ↓↓，RBC正常或↓某些细胞功能紊乱，如生物氧化、细胞呼吸小细胞低色素性贫血神经递质分解与合成等

血液系统症状非血液系统症状一般贫血表现行为发育异常髓外造血表现皮肤粘膜损害心血管系统症状细胞免疫功能↓缺铁性贫血发病机理2020/11/331

IronstudyIronstudyIDIDEIDA*serumferritin(SF)↓↓↓↓↓Ironstore↓↓↓↓↓FEP(红细胞游离原卟啉）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

（营养性巨幼细胞性贫血）

FolicacidandvitaminB12deficiencyareprimarycausesofmegaloblasticanemia.2020/11/340Case2.

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

PE:emotionalexpressionSluggishness（呆滞）,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叶酸↓四氢叶酸↓核苷酸尤其胸苷合成↓

VitB12↓DNA合成↓RNA合成正常神经髓鞘中脂细胞分裂↓蛋白质,如Hb蛋白合成不足细胞增殖↓合成正常

神经纤维功能细胞巨幼变不完整细胞数量下降

表情呆滞,反应差RBC↓WBC↓PLT↓其它组织发育落后,常倒退细胞↓肢体震颤可有病理反射

精神神经症状巨幼细胞性贫血营养性巨幼细胞性贫血发病机理

2020/11/353Answer

InthemacroblasticanemiaproducedbydeficiencyofvitaminB12,thesymptomsandsignsincludethoseofanemiaandneuropathy.Patientsdevelopademyelinatinglesionofneuronsofthespinalcolumnandcerebralcortex.Thisconditionresultsinparesthesias(感觉异常)ofthehandsandfeet,unsteadinessofgait,andeventuallymemorylossandpersonality（智力）changes.Thereisretardofintellectiveandphysicaldevelopment.Trembling（震颤）ofExtremitiesorhead,hypertensionofmuscle,tendonreflexreinforcement,positiveBabinski'ssignmayappear.

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

TodistinguishthedeficiencyoffolicacidwiththedeficiencyofvitaminB12