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Path - Chapter 10
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| Question | Answer |
|---|---|
| What are the major causes of infant mortality? | congenital anomalies; prematurity complications; low birth weight; SIDS |
| After 1 year of life, what constitute the majority of deaths in children? | Accidents |
| This group of congenital anomaly is caused by extrinsic effects during morphogenesis, and is exemplified by amniotic bands? | disturbances |
| A baby is born with clubbed feet, this is the mother's first pregnancy, what are some other factors that could have resulted in this DEFORMATION? | [Uterine constraint] we have ; 1st pregnancy, small uterus, malformed uterus, leiomyomas, oligohydramnios, multiple fetuses |
| A baby is born with flattened facies, hypoplastic lungs, clubfeet, and amnion nodosum is noticed as well. What fetal problem could have caused this sequence of events? | [Potter] renal agenesis |
| T/F Malformations are usually multifactorial while syndromes are normally caused by a single localizing event? | TRUE; |
| What is the difference between agenesis and aplasia? | both have absence of organs; Aplasia you have primordium but it doesn’t develop; Agenesis you don’t even have the primordium |
| What is the only karyotipic abnormality that has a birth frequency of greater than 10 in 10,000? | trisomy 21 |
| What is holoprocencephaly? | deformation where the brain fails to form two hemispheres; Hedgehog GENE |
| Gain of function mutation in FGFR3 (fibroblast growth factor receptor 3) will cause what inherited anomaly? | achondroplasia (short-limb dwarfism; AutoDOM; "short people are only 3 feet tall (FGFR3)" |
| What is the at-risk period for rubella infection in the pregnant mother in which anomaly can be caused by this virus? | shortly before conception to the 16th week |
| A pregnant mother aquires a viral infection during her 8th weel of gestation, the baby is born but has cataract, deafness, mental retardation, and a patent ductus arteriosus. Is the virus (ssRNA, ssDNA, dsRNA, dsDNA)? | [Congenital Rubella Syndrome] Rubella is a single stranded RNA virus |
| A baby is born with mental retardation, microcephaly, deafness, and hepatosplenomegaly. The mother had an intrauterine infection during her 2nd trimester with what virus? | Cytomegalovirus |
| These antineoplastic agents (cancer drugs) should not be given to patients of reproductive age because of their ability to cause limb abnormalities? | Thalidomide (used to treat multiple myeloma) |
| A baby is born with microcephaly, ASD, short palpebral fissure, and maxillary hypoplasia, and growth retardation. This is a classic teratogenic phenotype of what? | fetal alcohol syndrome (the three prominent facial features are thin upper lip, smooth philthrum, and small palpebral fissure) |
| A baby is born and is overweight, has increased body fat, muscle and organomegaly, cardiac anomalies, and neural tube defects. The mother likely has what disease? | Diabetes (maternal hyperglycemia- induced fetal hyperinsulinemia) |
| What is the most common birth defect that is orofacial? | cleft lip with and without cleft palate |
| These are the three most common cardiovascular birth defects? | tetralogy of fallot, transposition of the great arteries, atrioventricular septal defect |
| These two are the most common central nervous system birth defects? | spina bifida without anencephalus; anencephalus |
| These are the most common Gastrointestinal birth defects in the US? | Rectal/large intestinal atresia/stenosis; Esophageal atresia/ tracheoesophageal fistula |
| These three are the most common muskuloskeletal birth defects in the US? | gastroschisis(intestines stick out of the body); diaphragmatic hernia; omphalocele (organs are covered) |
| Epilleptic mothers need to be carefully treated during pregnancy because this anti-epilleptic drug is capable of inducing congenital birth defects such as tigonoencephaly by altering HOX expression? | Valproic Acid (VPA) |
| What weeks of the embyonic period (1st 9 weeks) is the embryo peaked sensitivity towards teratogenic insult (organs are being crafted out of germinal cell layers)? | 4th and 5th weeks |
| A 19 year old mother with severe acne gave birth to a child with birth defects such in CNS, cardiovascular system and cleft lip and cleft palate, what happened? | Vitamin A (teratogen - retionic acid given to her to treat her acne) |
| Babies born befor this week are termed preterm? | 37 weeks |
| Babies born after this week are termed postterm? | 42 weeks |
| This is the second most common cause of neonatal mortality after congenital anomalies? | prematurity |
| What are some risk factors for PPROM? | prior preterm delivery, preterm labor, vaginal bleeding, smoking, low socioeconomic status, poor maternal nutrition; Polymorphims in TNF and MMPS (collagen breakdown) |
| What is the general mechanism proposed for inflammation iduced preterm labor? | infection > upregulation of TLR4 > signals > deregulates prostaglandin expression > induce uterine smooth muscle contraction |
| What are the general causes of prematurity? | PPROM; Intrauterin infection (TLR4); Structural abnormalities in the reproductive system of the mother; multiple gestation |
| proportionate FGR is more commonly seen with (fetal infection, placenta previa, confined placental mosaicism, or umbilical-placental vascular anomolies)? | Fetal infection; Symmetric FGR is more common with fetal factors such as chromosomal disorders, congenital anomalies, and congenital infections |
| These vascular diseases are most likely the underlying cause of maternal linked FGR? | preeclampsia and chronic hypertension |
| What are the maternal factors affecting FGR? | vascular diseases (preeclampsia and hypertinsion); thrombophilias, hypercoagulability; narcotics, alcohol, cigarettes, malnutrition |
| A preterm baby is born AGA to a diabetic mother with C-section, after about 30 minutes he becomes cyanotic and upon chest exam rales can be heard. X-ray reveals a ground glass appearing picture (uniform minute reticulogranular densities) what happened? | RDS (hyaline membrane disease); Diabetic (insulin in fetus suppresses surfactant production); C-section (labor increases surfactant synthesis) |
| Fetuses with intrauterine stress and FGR are (more or less susceptible) to hyaline membrane disease? | LESS (cortisol actually increases surfactant levels) |
| What is surfactant consist of? | dipalmatyl phosphatidylcholine, phosphatidylglycerol, SPA and SPD(innate immunity); SBC and SBB (surfactant functions) |
| After what week is surfactant synthesis increased by type 2 alveolar cells? | 35th week |
| Describe the process that leads to the formation of hyaline in RDS? | poor surfactant > atelectasis > hypoxemia/CO2 retention > acidosis > pulm vasoconst > pulm hypoperfusion > endo-/epithelial damage (ischemia) > plasma, fibrin leak into alveoli > hyaline memb form > inc diffusion gradient; more hypoxemia/CO2 retention |
| Autopsy of infants lung reveals solid, airless lungs, that are reddish-purple and sink in water. What is the cause? | RDS (hyaline membrane disease) |
| In utero prophylactic treatment of RDS involves what? | exogenous surfactant; and corticosteroids |
| Once the infant is born with RDS what is the cornerstone of delivery of treatment? | surfactant therapy and oxygen |
| What are the two major complications with Oxygen therapy (oxygen toxicity)? | retrolental fibroplasia (retinopathy of prematurity) and bronchopulmonary dysplasia |
| What are the changes in VEGF expression that occur under oxygen treatment of RDS that lead to retrolentil fibroplasia? | Hyperoxic phases decreases VEGF causing endothelial cell apoptosis; Phase 2return to normal room ventilation causes VEGF increase and subsequent neovascularization of the eye) |
| What are the new major abnormalities in bronchopulmonary dysplasia? | decreased alveolar septation (due to oxygen, mechanical ventilation, pro-inflammatory cytokines) and dysmorphic capillary (reduced VEGF) configuration |
| A preterm infant suddenly has onset of bloody stools, abdominal distention, and circulatory collapse. X-ray reveals pneummatosis intestinalis. What inflammatory mediator is likely to be seen in the stool and serum samples of this infant? | [NEC necrotizing enterocolitis] PAF is likely to be seen (platelet activating factor) |
| What are the two routes of perinatal infection? | transcervically (ascending) and transplacentally (hematologic) |
| What are two ways that a fetus can aquire an ascending infection? | inhalation of infected amniotic fluid (pneumonia, meningits, sepsis); passing through infected birth canal |
| Most bacteria (except listeria and treponema) are fetal aquired by which mannaer (ascending or transplacentally)? | Ascending |
| This virus passed transplacentally causes erythema infectiosum in older immunocompetent children, and can cause spontaneous abortion, stillbirth, hydrops fetalis, and congenital anemia in newborns? | parvovirus B19 |
| This organism is the most common cause of early-onset sepsis and bacterial meningitis? | Group B streptococcus |
| This is accumulation of edema fluid in the fetus during intrauterine growth? | Fetal Hydrops |
| T/F ABO incompatibility between mother and fetus will NOT result in Rh immunization and consequent hemolytic disease of the newborn? | TRUE; |
| What are the factors associated with the fact that ABO incompatibility related hemolytic anemia of the newborn is less common and less severe than Rh antimbody mediated hemolytic anemia? | anti-A/B antibodies are IgM and don't cross placenta ( unless you have an O-blood mother who makes them out of IgG); newborn red cells express antigen weakly; other cells express these antigens and absorb the antobody |
| Can a mother of A blood type have a hemolytic anemia with a baby of B blood type? | NO mother must be O group |
| In what instance can a mother with no previous pregnancy give birth to a child with hemolytic anemia? | previous Abortion; or ABO blood group incompatibility (O group mother makes anti-A and anti-B antibody w/o previous sensitization) |
| What is the cause of generalized edema and anasarca in babies with hemolytic anemia? | liver injury (decreased plasma |
| In what chromosomal abnormality will we see postnuchal fluid accumulation (cystic hygroma)? | 45, X (turners) |
| What are the three major categories of causes of nonimmune hydrops? | cardiovascular, chromosomal, fetal anemia |
| These three chromosomal anomalies are associated with nonimmune hydrops? | Turners, Trisomy 21, and 18 |
| How can parvovirus B19 lead to nonimmune hydrops? | Development of fetal anemia; it is tropic for erythroid precursor (normoblast) cells and infects and lyses these cells) |
| What can be seen in the liver, spleen and lymph nodes of fetus with nonimmune hydrops fetalis due to fetal anemia? | large numbers of reticulocytes, normoblasts, and erythroblasts due to compensatory menatopoitec activity |
| What is the most serious threat in fetal hydrops? | kernicterus |
| What color will the enlarged and edematous kernicterus brain be (particularly the basal ganglia, cerebellum, thalamus, and cerebral cortex, and spinal cord)? | YELLOW |
| Two fetal anemia causes of non-immune hydrops fetalis? | homozygous a-thalassemia; parvovirus p19 |
| T/F twin-twin transfusion of monozygotes can cause non-immune hydrops fetalis? | TRUE; |
| These three infections can cause hydrops fetalis (excluding parvovirus B19)? | cytolomegavirus; syphilis; toxoplasmosis |
| Autosomal recessive, hyperphenylalaninemia, phenylalanine hydroxylase mutation? | PKU |
| These persons test positive for PKU but do not develop the stigmata of classic PKU | Benign hyperphenylalaninemia |
| This patient has a PKU variant in which the dietary control of phenylalanine does not arrest neurological damage, what is the likely mutation? | BH4 recycling mutation (dihydropteridine reductase) |
| Phenylalanin to tyrosine conversion happens in what organ of the body? | Liver |
| What is the diagnostic significance of the shunting of the phenylalanine to tyrosine pathway into metabolite production such as phenylacetic acid? | Excreted in sweat (musty / mousy odor) |
| What is the cause of the brain damage seen in patients with uncontrolled PKU? | Phenylalanine metabolites |
| A mother who has PKU and stops treatment gives birth to a child, what could be wrong with the child? Does the child have PKU? | mental retardation, microcephaly, and congenital heart disease (child is NOT PKU, but effects of PKU are transferred) |
| What are the two enzyme deficiencies that result in galactosemia and which is more common? | galactose-1-phosphate uridyl transferase (more common) and galactokinase |
| What are the more dominant features of galactosemia? | hepatomegaly (due to fatty change); Cataract (lens swelling); nonspecific alteration of CNS (LON, gliosis, edema of dentate nuclei and olivary nuclei) |
| What is the cause of the aminoaciduria in patients with galactosemia? | accumulation of galactose and galactose-1-phosphate in the kidney |
| Patients with galactosemia have an increased frequency of what infection? | E. Coli septicemia (diminished neutrophil bactericidal activity) |
| Even after treatment of galactosemia, what are older patients with the disease more likely to suffer from? | speech disorder, gonadal failure, and ataxia |
| What is the most common lethal genetic disease that affects caucasian populations? | |
| Autosomal recessive, chronic lung disease due to secondary infections (recurrent), pancreatic insufficiency, steatorrhea, malnutrition, hepatic cirrhosis, intestinal obstruction, male infertility? | Cystic Fibrosis |
| CFTR regulates multiple additional ion channels via its cytoplasmic nucleotide binding domain, but this interaction has the most pathophysiologic relevance in cystic fibrosis? | ENaC (uptake of sodium from luminal fluid) |
| Enac is increased or decreased in CFTR mutations in Cystic Fibrosis? | Increases in pulmonary and gastrointestinal but DECREASES in sweat glands ("salty" sweat) |
| What is the function of normal CFTR in the sweat glands? | REABSORBTION of chloride and NA (via ENAC) |
| In respiratory and intestinal epithelium, what is the function of CFTR? | secretion of CL, and inhibition of Na reabsorbtion of ENaC |
| T/F there is a difference in the salt content of the mucus coating the respiratory and intestinal epithelium between cystic fibrosis and normal patietns? | NO difference (FALSE); isotonic but LOW volume surface fluid layer |
| In patients with a defect in this cystic fibrosis variant, chloride transport is preserved, but highly acidic secretions are the pathogenic mechanisms that result in complications? | Mutations that effect bicarbonate transport (WHICH CFTR mediates) |
| These two classes display a complete lack of CFTR protein? | 1 and 2 Class 3 has nonfunctional CFTR protein |
| These two classes display a milder phenotype of cystic fibrosis? | 4 and 5 |
| What are the 6 classes of mutations affectign cystic fibrosis? | 1(defective protein synthesis); 2(abnormal folding, processing, trafficking); 3(defective regulation ATO binding); 4(decreased conductance); 5(reduced abundance); 6 (altered regulation of separate ion channels) |
| What genetic and environmental modifiers can induce the phenotypic expression and severity of cystic fibrosis? | genetic (MBL2 and TGF-B); Environmental (virulence of organisms, efficacy of therapy, intercurrent and concurrent infections) |
| What is a reason for the stunded growth and impaired post-natal development seen in pateints with cystic fibrosis (pancreatic)? | Malabsorption die to achylia |
| With cystic fibrosis, malabsorption of the fat-vitamins ADEK occur. Which vitamin deficiency will lead to squamous metaplasia of the lining epithelium of the ducts in the pancreas? | Vitamin A (avitaminosis) |
| Of the three most common respiratory infection (S. aureus, Hemophilus influenza, pseudomonas aerigunosa) which one takes full advantage of the static mucus hypoxic environment to creat and alginate biofilm to protect itself from immune response? | Pseudomonas Aerigunosa |
| What is a frequent finding in the reproductive system of males with cystic fibrosis? | absence of vas deferans (azoospermia/infertility) |
| Of the Burkholderia Cepacia Complex pathogenic organisms, this one is the most common in patients of cystic fibrosis, and requires longer hospital stays, and increased mortality ? | "cepacia syndrome" B. cenocepacia (gram-negative; catalase producing; obligate aerobe; rod) |
| An infant is born with meconium ileus, and dies a few months later. Upon autopsy what might his liver show? | Steatosis, focal biliary cirrhosis (occurs later in life) |
| What disease shows dilation of ducts, squamous metaplasia, and glandular atrophy in both the salivary glands and the pancreas? | cystic fibrosis |
| What are some clinical manifestations of malabsorption in patients with cystic fibrosis? | large, foul smelling stools; Abdominal distention, poor weight gain; edema secondary to hypoprotenemia; Rectal prolapse (due to diarrhea) |
| This obstructive lung disease is present in patients with cystic fibrosis (pulmonary fibrosis, asbestosis, emphysema, bronchiectasia)? | Bronchiectasa (emphysema is obstructive but not present; both asbestosis and pulmonary fibrosis are restrictive) |
| Which of these is present in a patient with cystic fibrosis (metabolic acidosis, metabolic alkalosis)? | Metabolic alkalosis (increase sweat output and loss of electrolytes causes ECF volume contraction and thus increase bicarbonate concentration) |
| This is the sudden unexplained death of a child less than 1 years of age? | SIDS (sudden infant death sydnrome) |
| What is the leading cause of death between 1 month and 1 year (90% between 2-4 months) in the US? | SIDS |
| These are the typycal postmotem findings in SIDS? | Multiple petechia; congested vascularly engorged lungs with or without pulmonary edema; astrogliosis; hypoplasia of the arcuate nucleus; extramedullary hematopoiesis; periadrenal brown fat) |
| What are the parental risk factors of SIDS? | young maternal age; maternam smoking; drug abuse; short intergestational intervals; late or no prenatal care; low socioeconomic class; African American and American Indian ehtnicity |
| What are the infant risk factors of SIDS? | Brain stem abnormalities; prematurity/low birth weight; male sex; multiples; SIDS in prior sibling; antecedent respiratory infections; germline polymorphisms in autonomic nervous system |
| What are the environmental risk factors of SIDS? | prone/side sleep; sleeping on soft surface; hyperthermia; co-sleeping in first 3 months of life |
| What are the post-mortem abnormalities detected in cases of sudden unexpected infant death? | infection (viral myocarditis, bronchopneumonia); Unsuspected cong anomaly (aortic stenosis, LT coronary a. from the pulm a.); Traumatic child abuse; genetic/metabolic defects (long QT, FA oxidation disorder, histiocystoid cardiomyopathy) |
| What are the post-mortem abnormalities associated with SIDS and infections? | viral myocarditis, bronchopneumonia |
| What are the post-mortem abnormalities associated with SIDS and congenital anomaly? | aortic stenosis; anomalous origin of the left coronary artery from the pulmonary artery |
| What are the post-mortem abnormalities associated with SIDS and genetic/metabolic defects? | SCN5A and KCNQ1 (long QT); MCAD LCHAD SCHAD (fatty acid oxidation); MTCYB (histiocytoid cardiomyopathy); partial deletions of c4a and c4b (classical pathway) |
| What are the components of the triple risk model of SIDS? | vulnerable infant; critical developmental period of homeostatic control; exogenous stressor |
| What is the most compelling hypothesis on the development of SIDS? | delayed development of arousal (serotonergic system of the medulla) and cardiorespiratory control |
| What is the safest sleeping position that reduces the risk of SIDS? | supine |
| What is a choristoma (heterotopia)? | a presence of microscopically normal cells or tissues that are present in abnormal locations (bengin and not bothersome) |
| What is a hamartoma? | excessive, focal overgrowth of cells and tissues native to the organ in which it occurs |
| These are the most common tumors of infancy? | hemangiomas |
| These lesions are located most commonly in the skin of children and appear as elavated, irregular, blue-masses (port-wine stains), can represent one facet of von hippel-lindau disease? | Hemangiomas |
| What are the clinical presentation differences between lymphangioma and lymphangiectasis? | lymphangioma increases in size with age and may encroach on vital structures; lymphangiectasis presents as diffuse swelling in part or all of the extremity |
| FISH analysis of a karyotype reveals a translocation between chromosome 12 and 15, producing a ETV6-NTRk3 fusion transcript. What is the result and what age group is primarily affected? | congenital-infantile fibrosarcoma (indistinguishable from adult fibrosarcomas) |
| These are the most common teratomas of childhood and more present in girls? | sarcococcygeal teratomas |
| Where do the most frequent childhood cancers arise? | hematopoetic system, nervous tissue, soft tissue, bone, kidney |
| Due to the histological features of (primitive embryonal appearance) the many childhood tumors show, what collective name do they all share? | small round blue cell tumors (neuroblastoma, wilms, lymphoma, rhabdomyosarcoma, eqing, medulloblastoma, retinoblastoma) |
| Neural crest cells derive this tumor? | neuroblastic tumors (neuroblastoma) |
| This gene mutation has been identified as a major cause of familial predisposition to neuroblastoma? | ALK (anaplastic lymphoma kinase) |
| Where are nueroblastic tumors often found? | sympathetic gangli and adrenal medulla |
| What are the most common sites of neuroblastoma formation in childhood? | adrenal medulla; paravertebral ganglia; posterior mediastinum ganglia |
| This tumor has histological charateristics of small primitive appearing cells with dark nuclei, scant cytoplasm (1:1), poorly defined cell borders, and often is arranged in rosettes (Homer-Wright pseudorossetes) about a central space filled with neuropil? | Neuroblastoma |
| Describe the histological features of the ganglioneuroblastoma? | large cells with abundant cytoplasm, large vesicular nuclei with prominent nucleolus, with shwann cells (ganglioneuromas are similar but more differentiated and fewer neuroblasts) |
| The appearance of schwann cells in nueroblastic tumors is (not favorable or favorable)? | Favorable |
| [What stage of neuroblastoma] localized tumor with compplete gross excision, with or without microscopic residual disease, representative ipsilateral nonadherent lymph nodes are negative for tumor? | Stage 1 |
| [What stage of neuroblastoma] localized tumor with incomplete gross resection, representative ipsilateral nonadherent lymph node negative for tumor? | Stage 2a |
| [What stage of neuroblastoma] Localized with or without complete excision; ipsilateral node positive; contralateral node enlarged negative? | Stage 2b |
| [What stage of neuroblastoma] unresectable unilateral tumor infiltrating across midline with or without regional lymph node involvement; OR ; localized unilateral tumor with contralateral regional lymph node involvement? | Stage 3 |
| [What stage of neuroblastoma] any primary tumor with dissemination to distant lymph nodes, bone, bone marrow, liver and skin? | Stage 4 |
| [What stage of neuroblastoma] localized primary tumor with dissemination limited to skin, liver and or bone marrow (only for less than 1 year)? | Stage 4S |
| Which two stages of neuroblastoma are unfavorable? | 3 and 4 (4S is favorable) |
| In neuroblastoma, is karyorrhexis > 200/5000 cells favorable or unfavorable? | Favorable (karyorrhexis is nuclear breakdown) |
| 17q gain, 1p loss, 11q loss are all (present or absent) in the unfavorable prognosis of neuroblastoma? | PRESENT |
| How are TRKA and TRKB expression used in prognosis of neuroblastoma? | If TRKA |
| What does the presence of vanillylmandelic acid [VMA] and homovanillic acid [HVA] represent? | increased production of catecholamines (90% of neuroblastomas produce catecholamines as well as pheochromocytoma) |
| What pathway do neuroblastomas typically metastisize through (lymphatic, hematogenous, Both)? | BOTH |
| What are the two most important determinants of neuroblastoma outcome? | Age(18mo) and stage (although amplification of N-Myc trumps these two things and is always unfavorable) |
| In neuroblastomas, which ploidy has a better prognosis (near diploid, hyper-diploid)? | Hyper-diploid) |
| How can retinoic acid be used to treat neuroblastoma? | induces differentiation of the tumor |
| This is the most common primary renal tumor in children? | Wilms Tumor |
| T/F Wilms tumor involves both kidneys? | TRUE; (synchronous or metachronous) |
| Wilms tumor is associated with this group of congenital malformations, which has defects in PAX6 and WT1, and is clinically manifested as aniridia (absence of the iris), genital anomolies, and mental retadation? | WAGR syndrome (THINK "wilms aniridia genital retardation) |
| Wilms tumors assoc w/ this syndrome display gonadal dysgenesis & nephropathy, diffuse mesangial sclerosis, & have a dominant negative missense mutation in the zinc finger DNA binding region of the WT1 gene. They are at increased risk for gonadoblastomas? | Denys-Drash syndrome (dysgenesis is kinda in the first name) |
| What is the WT1 protein critical for development of? | normal kidney and gonads |
| These patients that develop Wilms tumor have organomegaly, macroglossia, hemihypertrophy, omphalocele, and adrenal cytomegaly? | BWS (beckwith-Weidmann syndrome) |
| BWS patients have overexpression of this "WT2" gene due to either loss of imprinting or uniparental paternal disomy (the maternally imprinted allele is deleted and the paternal duplicated)? | IGF2 |
| These are precursor lesions of WILMS tumor and are seen in the renal parenchyma? | Nephrogenic rests |
| The presence of what in Wilms tumor correlates with the resistance of chemotherapy? | anaplasia (p53 mutations) |
| What are the histological features of Wilms? | Blastemal (small blue cells in sheets); epithelial (abortive tubules or glomeruli); stromal (connective tissue) |
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