ap 50 10-22 1 diseases of infancy and childhood
TRANSCRIPT
Disease of Infancy and Childhood
Diseases of infancy and childhood
Terminology -Neonatal peroid: first 4 wks. Early: first 7 days,Late: after 7 days
-Infancy : 1 yr. -Early childhood: 1-4 yr. -Late childhood : 5-14 yr. -Newborn : 24 hr. -Perinatal death = neonatal death+fetal death
Body weight and gestational age
• Preterm : 37 wk.• Posterm : 42 wk.• AGA: BW ( 10-90 Percentile )
• SGA: BW ( < 10 Percentile )
• LGA: BW ( > 90 Percentile )
CAUSE OF DEATH
Intrauterine growth retardation (IUGR)
Etiology : Unknown : Fetal – Chomosome abn ( tripoid, trisomy 18,17, 21, other ) , congenital anomaly,TORCH
: Placenta –UVP anomaly, mosacism(genemutate in zygote:trisomy 7 )
: Maternal –Vascular( HT), narcotic, ALG,smoking, drug, malnutrition.
Immaturity of organs
Lung : (26-32 wk) alveolar epi. type I– II respiratory distress syndrome ( RDS )Kidney : premature glomeruliBrain : No gyri, sulci --- def. of myelin – eff. control temp.Liver : Extra med. ----transcient phy. jaundice
APGAR SCORE
Method for evaluate phy. condition --- survival
Score at 5 min (0-1) ---- death 50% 4 ---- death 20% >7 ---- death 0 %
Evaluation of new born
Stillbirth
• No sign of life(> 20 wk)• DFIU,intrpartum death (DR= 0.55-
1.93LA)• Etiology :chr.abn, IUGR,maternal,
perinatal infection, immuno dis., intrapartum hem, postterm
Birth injuried :
Clavicle Fx ,facial N , brachial plex ,intraclanial inj.humural Fx.
Birth injuries of head 1.Intracranial hemorrhage :most common important birth injury -excessive mold skull --- subdural,subarachnoid. intraventricle hem. ---- ICP --- brain herniation ---- vital med. center
2. Caput succedaneum ---- fluid in soft tiss. of scalp ,Cephalhematoma ---- subperiosteum hem. of scalp , 25% skull fracture
Definitions
• Malformations; morpho. def of organs---
result abn. develop Dysplasia; abn. organized cells in tissue
Deformations; abn form ,shape, position of body by mechanic.
Disruptions; defect of organs by ext. breakdown
Sequences: pattern anomaly from single known
Cause of con genital mal
Definitions (continues)
• Syndrome: multiple anomalies,not
representing sequence from single agent( viral or chromosome abnormal )
Association: non random occur in several
defect ,not seqeunces and syndrome
Descriptive terms
• Agenesis: complete absence of organ
• Aplasia: absence of organ due to failure del.
• Atresia: absence of opening hallow visceral organ
• Hypoplasia: under del. of organ, decrease No. cells
• Hyperplasia: over del. of organ, increase No. cells
• Hypotrophy: decrease in size of cells
• Hypertrophy: increase in size of cells.
Descriptive terms (continue)
• Dysraphic: failure to fuse: e.g. spinal bifida
• Involutional failure: persist emb.stru. e.g. thyroglossal duct cyst
• Division failure: incomplete cleave tissue e.g. syndactyly
• Ectopia or heterotopia; organ outside normal site
• Dystopia: retention of organ at site during development
Figure 11-7
Cause of malformations
Genetic cause: karyotypic aberration( 10-15 %) birth
life e.g. trisomy 21. Klinefelter syn , Turner syn, trisomy 13 (Patau syndrome) : single gene mutation e.g. polydactyly :mutlifactorial inheritance
Environmental cause: viruses :esp rubella, CMV
: drugs and chemical e.g. alcohol : radiation
Multifactorial causes
Mechanism of malformations
Timing perinatal mal: -Embryonic period (organogenesis) 9 wk.
-Early in 3 wk may normal or abortion -Between third and ninth wk (4-5 wk) -Fetal period :growth and maturation of organ
Teratogens: -effect cell pro.,migration and differentiation
e.g.anticonvulsant drug --- dediff. mesenchymal tissue –
cleft palate
Morphogenic gene: Hox gene
Perinatal infection Transcervical(ascending) infection -bacteria, virus ( herpes simplex II )— Intrauterine
pneumnia,sepsis,meningitis.
Transplacenta(hematologic) infection - Virus: e.g. TORCH : hepatosplenomegaly,
hem.anemia,pneumonia, myocarditis, vesicular skin : MD, cataract, CHD, bone defect
: Parvovirus B 19 : replication in RBC (intra nuclear
inclusion) ---- abortion, stillbirth, HF.
-Bacteria : Group B strep: most common early sepsis :most common bact. meningitis
: Listeria and candida : late sepsis
parvovirus
Respiratory distress
• HMD , sedation , brain inj , AFA , IUA
• HMD: preterm ,term with DM , C/S : 30 min after birth ---tachypnea --
cyanosis --- ground glass x-ray
: 60% less than 28 wk, 15-20% 32-36 wk.Gross: Airless+ solidMicro: atelectasis+ overdistend alveoli+pink
membrane on air spaceSequelae : RLFP,fibrosis BPD , IVH, NEC
Fig11-10
Meconium aspiration syndrome (MAS)
-Asphyxia --- abn. rep.motion---amniotic fluid
in air space- Micro: meconium( desquamate squamous
cells,bile pigment, lanugo hair)
Hydrop fetalis
subcutaneous edema+ effusion in
pericardial,peritoneum, pleural cavity. -Mech: anemia + decrease protein---
decrease intravacular pressure ----- leak of fluid
-Cause : immune ---erythroblastosis fetalis : nonimmune > 90%
Fig 11-12
Table 11-5
Inborn errors of metabolism
- Phenylketonuria : homozygote AR --- lack
phenylalanine hydroxylase – PKU--- mental retard- Galactosemia : homozygote AR --- lack of
galactokinase---- galactitol -----MD, cataract, hepatosplenomegaly, failure to thrive, diarrhea
- Cystic fibrosis: defect Cl transport in epithelium
cells by cystic fibrosis gene (chr 7) --- exocrine in respiratory, GI tract, reproductive organ
: poor weight gain, malabsorption,
pulmonary problem
Sudden infant death syndrome(SIDS)
90% SIDS less than 6 m,unexplained by autopsy,
heterogeneous entity,sleep at night ,healthy Micro: anoxic change : VH, gliosis,
pulmonary congestion , petechial hem. at pleura etc.
Neoplasm most benign, 2% malignant
Hemangioma :most common tumors in infancy
:skin, face,scalp Gross: red blue mass Micro: numerous vessels with unremarked endothelium : Spontaneous regress :asso hereditary e.g. von Hippel-Lindau dis.
Lymphangioma : skin ,neck,axilla,mediastenal,retro.
:micro :lymph vessels in cyst or space :increase in size after birth
Teratoma : 2 yr or adolescence,sacrococcygeal
Gonad,medias, retroperitoneum,head neckSacrococcygeal teratoma : 1:20000-40000 : M/F=4:1
-10% asso congen.def hind gut,mid line defects - Gross: cystic mass with mature tissue - Micro : meso,endo and ectoderm. - 75% mature contains mature tissue -12% immature contains mature and immature tissue - 12.5 % mixed germ cell tumor
Malignant tumor in infancy
abn.del and tumor inductionfamilial or genetic aberrations : regress spon. or cytodiff. , improve survival and cure.
Common : hemato malignancy. , nervous system, soft tissue,bone, kidney.
Neuroblastoma Vs ganglioneuroma
Most common childhood solid mal. tumorMost common diag. less than 1 yr.Location: 25-35% adr. med ,symp chain
(paravertebralpost.mediastinum or lower abdomen)Gross: minute nodule to huge massMicro: small blue round cells with neurofibrillary(Homer-Wright) diff. to ganglia cells(psuedorosettes)--- ganglioneuroma , ganglioneuroblastomamet to blood stream --- liver, lung, bone
Clinical staging
• Stage 1 : confined in organ origin• Stage 2: extened beyond organ, not cross mid
line• Stage 3: beyond midline• Stage 4: metastasis to viscera, distal LN, soft
tiss.. skeleton Stage 5s (special) :small adr. tumor to liver,skin, bone marrow without bony destruction
Clinical course
Most < 2 yr , fever , abdominal mass,weight loss, proptosis
Prognosis ; < 1 yr--- excellent prognosis (no related stage)
< 1 yr.stage 1,2 ---- 95-98 % 5 yr. survival Stage 5 s ---- 80% 5 yr. survival Chromsome 1 deletion ---- worse prognosis 25-50% asso deletion of q chr.14 ---
agg.behavior
Groups of prognosis
First gr : < 1 yr, hyperploid, high Trk A, no n myc
oncogene,adsence of deletion chr.1p, stage 1,2,5
s --- cure rate 90%
Second gr: older , more stage
Third gr: worse prognosis , 1-5 yr, advance stage,
n myc oncogene ,diploid, deletion chr. 1p ,mini Trk A
----- cure rate 5%
Micro homerise roset
Fluorescence in situ hybridization for N myc
Wlim’s tumor(nephroblastoma)- Most common childhood solid malignant tumor - Incidence 2-5 yr.- Survival rate > 90%- Asso three gr. malformation; aberration in chr 11p- 1) WARD syndrome : wilm’s ,aniridia,MR , genital
anomaly,deletion of 11p13 (WT-1 locus)- 2) Denys-Drash syndrome; gonodal dys.(male psuedohermaphroditism,nephropathy,wilm’s , missense
mutationof 11p13 (WT-1 locus) 3) Beckwith-Widerman syndrome: enlarge organ,
hemihypertrophy renal medullay cyst, wilm’s, adrcytomegaly , 11p15 (WT-2 locus)
Gross :large solid, well circum mass(10% bilat or multicentric) ,focal hem,cystic degeneration and necrosis
Micro: triphasic combination of
1.Blastemal com: primitive small blue cell. predominate------ stage 3 or 52.Stromal com: fibrocytic or myxoid stroma3. Epithelium com: abortive tubules and glomeruli, predomonate----- stage 1 5% of tumor analplasia (abn mitoses, pleo,hyper)----resistent Tx