ABPath Pediatric Pathology flashcards

32 cards. Read the term and the definition here. The deck at the top of this page is optional.

Neural tube closure

Anterior neuropore closes ~day 26 and posterior neuropore ~day 28; failure causes anencephaly or spina bifida.

Folate and neural tube

Periconceptional folic acid supplementation reduces recurrence risk of neural tube defects by up to 70%.

Birth weight triples

Infant birth weight triples by 1 year and quadruples by 2 years; length increases ~50% by 1 year.

Maternal IgG transfer

Maternal IgG crosses placenta via FcRn mainly after 32 weeks; IgM does not cross, so neonatal IgM indicates fetal infection.

RhD alloimmunization

Fetomaternal hemorrhage sensitizes RhD-negative mothers; RhIG prophylaxis prevents hemolytic disease of the newborn.

Maternal PKU effect

Poorly controlled maternal phenylketonuria causes microcephaly, intellectual disability, and congenital heart defects in the fetus.

Placenta previa

Implantation over or near the internal cervical os causes painless third-trimester bleeding; cesarean delivery is often required.

Placental abruption

Premature placental separation causes painful bleeding, retroplacental hematoma, and fetal distress; risk with hypertension and trauma.

Oligohydramnios

Amniotic fluid index below 5 cm; associated with renal agenesis, obstruction, and Potter sequence with pulmonary hypoplasia.

Polyhydramnios

Amniotic fluid index above 24 cm; associated with esophageal atresia, anencephaly, and maternal diabetes.

Stillbirth definition

Fetal death at 20 weeks gestation or later; causes include placental insufficiency, infection, cord accident, and anomalies.

Maceration

Skin slippage and reddening after intrauterine death; degree estimates interval between death and delivery.

Hydrops fetalis

Abnormal fluid accumulation in two or more compartments; immune (Rh) or non-immune (cardiac, aneuploidy, parvovirus).

NEC hallmark

Necrotizing enterocolitis in preterm infants shows pneumatosis intestinalis on radiography; ischemic and infectious contributors.

VACTERL association

Vertebral, anal, cardiac, tracheoesophageal, renal, and limb anomalies; diagnosis requires at least three features.

Potter sequence

Renal agenesis causes oligohydramnios, leading to pulmonary hypoplasia, limb deformities, and characteristic flat facies.

DiGeorge syndrome

22q11.2 deletion causes conotruncal cardiac defects, thymic hypoplasia, and hypocalcemia from parathyroid hypoplasia.

Down syndrome features

Trisomy 21 is associated with endocardial cushion defects, duodenal atresia, and Hirschsprung disease.

MCAD deficiency

Fatty acid oxidation defect causing hypoketotic hypoglycemia and sudden death during fasting or illness.

Galactosemia

GALT deficiency causes jaundice, hepatomegaly, cataracts, and E. coli sepsis; treatment avoids galactose.

Chronic granulomatous disease

NADPH oxidase defect causes recurrent catalase-positive infections and granulomas; diagnosis by oxidative burst testing.

Congenital CMV

Causes periventricular calcifications, microcephaly, sensorineural hearing loss, and petechiae; leading congenital infection.

Congenital toxoplasmosis

Causes diffuse intracranial calcifications, hydrocephalus, and chorioretinitis; acquired from maternal primary infection.

Parvovirus B19

Causes hydrops fetalis through aplastic crisis and myocarditis; no vaccine available.

Neuroblastoma markers

N-myc amplification, elevated urinary catecholamines, and bone marrow metastases characterize this pediatric tumor.

Wilms tumor

WT1 mutation; associated with WAGR, Denys-Drash, and Beckwith-Wiedemann syndromes; arises from nephrogenic rests.

Retinoblastoma

RB1 biallelic inactivation causes leukocoria and intraocular calcification; heritable cases are bilateral and early.

Flow cytometry CD45

CD45 identifies leukocytes; surface markers establish lineage and clonality in pediatric leukemia and lymphoma.

FISH utility

Detects translocations and amplifications such as N-myc on interphase cells, useful when karyotype is not possible.

Newborn screening

Heel-stick dried blood spots detect PKU, congenital hypothyroidism, CAH, and hemoglobinopathies before symptoms appear.

SIDS diagnosis

Diagnosis of exclusion requiring complete autopsy, scene investigation, and review of history; no pathognomonic findings.

Westgard rules

Quality control rules detect systematic and random error; 1-3s and 2-2s violations indicate rejection or warning.