Diseases of Infancy and Childhood

Question 1

These represent primary errors of morphogenesis due to an intrinsically abnormal developmental process; example: Polydactyly

Answer 1

Malformations

Question 2

These result from secondary destruction of an organ or body region that was previously normal in development, due to an extrinsic disturbance in morphogenesis; example: Amniotic bands

Answer 2

Disruptions

Question 3

These are due to generalized compression of the growing fetus by abnormal biomechanical forces; example: Uterine constraint

Answer 3

Deformations

Question 4

This refers to multiple congenital anomalies that result from secondary effects of a single localized aberration in organogenesis. The initiating event may be a malformation, deformation or disruption; example: Oligohydramnios (Potter) sequence

Answer 4

Sequence

Question 5

Complete absence of an organ or its anlage.

Answer 5

Agenesis

Question 6

Incomplete development of an organ.

Answer 6

Aplasia

Question 7

Underdevelopment of an organ.

Answer 7

Hypoplasia

Question 8

Absence of an opening, usually of a hollow visceral organ.

Answer 8

Atresia

Question 9

Most common cause of neonatal mortality.

Answer 9

Congenital anomalies

Question 10

Most common cause of congenital malformation in humans.

Answer 10

Unknown (40-60%)

Question 11

Most common known cause of congenital malformations in humans.

Answer 11

Multifactorial (20-25%)

Question 12

Most common genetic cause of congenital malformations in humans.

Answer 12

Chromosomal aberrations

Question 13

Elements of the TORCH complex.

Answer 13

Toxoplasma, Others (Treponema pallidum), Rubella, Cytomegalovirus, Herpesvirus

Question 14

Second most common cause of neonatal mortality.

Answer 14

Prematurity

Question 15

Histologically characterized by eosinophilic membranes line the respiratory bronchioles, alveolar ducts and random alveoli, which contain necrotic epithelial cells, admixed with extravasated plasma proteins (Diffuse alveolar damage).

Answer 15

Respiratory distress syndrome of the newborn (Hyaline membrane disease)

Question 16

Main component of pulmonary surfactant; which is insufficient in hyaline membrane disease.

Answer 16

Dipalmitoylphosphatidylcholine (DPPC)

Question 17

A complication of hyperoxic therapy in patients with RDS, resulting in neovasculatization of retinal vessels, leading to blindness.

Answer 17

Retinopathy of prematurity (ROP)/Retrolental fibroplasia

Question 18

A complication of hyperoxic injury in patients with RDS, resulting in alveolar hypoplasia or a decrease in the number of mature alveoli; morphologically, there is large, simplified alveolar structures, and a dysmorphic capillary configuration.

Answer 18

Bronchopulmonary dysplasia (BPD)

Question 19

This condition occurs more commonly in very-low-birth-weight infants, as a result of intestinal ischemia, bacterial colonization of gut and formula milk feeding; histologically, there is presence of submucosal gas bubbles, transmural coagulative necrosis, ulceration, and bacterial colonization.

Answer 19

Necrotizing enterocolitis (NEC)

Question 20

Results from antibody-induced hemolytic disease in the newborn that is caused by blood group incompatibility between mother and fetus, leading to edema fluid accumulation; examples: ABO and Rh incompatibility

Answer 20

Immune hydrops

Question 21

Hydrops caused by cardiovascular defects, chromosomal anomalies, and fetal anemia.

Answer 21

Nonimmune hydrops

Question 22

Inherited disorder of ion transport that affects fluid secretion in exocrine glands and in the epithelial lining of the respiratory, gastrointestinal, and reproductive tracts; most common lethal genetic disease affecting Caucasian populations; involved gene is CFTR-1 in Ch7q31.2.

Answer 22

Cystic fibrosis (CF)

Question 23

Defined as the sudden death of an infant under 1 year of age which remains unexplained after a thorough investigation; characteristic findings include: multiple petechiae of the thymus, visceral and parietal pleura and epicardium, congested lungs with vascular engorgement with or without pulmonary edema; there is also hypoplasia of the arcuate nucleus.

Answer 23

Sudden infant death syndrome (SIDS)

Question 24

Tumors arising from neural crest cells; composed of small, primitive-appearing cells with dark nuclei, scant cytoplasm, and poorly defined cell borders growing in solid sheets within a finely fibrillar matrix (neuropil: eosinophilic fibrillary material that corresponds to neuritic processes of neuroblasts); associated with Homer-Wright pseudorosettes.

Answer 24

Neuroblastoma (Classically described as a mass crossing the midline, vs. Wilms tumor that does not cross the midline)

Question 25

Most common primary tumor of the kidney in children; second most common primary tumor of the kidney overall (next to RCC); presents grossly as a large, solitary, well-circumscribed mass; microscopically, a combination of blastemal, stromal and epithelial cell types is observed (Triphasic combination); blastemal components are described as sheets of small blue cells with few distinctive features; stromal cells are fibrocytic or myxoid in nature; epithelial cells take the form of abortive tubules or glomeruli.

Answer 25

Wilms tumor