Pediatrics - Congenital structural and biochemical disorders Flashcards
PED - 3.1
Typical signs/symptoms of Down syndrome include the following, except for one:
A) brachycephaly
B) epicanthus
C) big tongue
D) cleft palate
E) muscle hypotonia
ANSWER
D) cleft palate
EXPLANATION
The major developmental disorders seen in the physical examination are rare in Down’s syndrome; most of the anomalies that can be seen are part of a group of minor anomalies (informative morphogenetic variants), some of which generate a distinctive appearance
PED - 3.3
The risk of a 41-year-old woman to give birth to a child with Down syndrome is:
A) 1: 100
B) 1: 350
C) 1: 800
D) 1: 1200
E) 1: 1850
ANSWER
A) 1: 100
EXPLANATION
According to statistics, the risk to develop Down syndrome increases in mothers over the age of 40, which justifies prenatal screening over 35 years.
PED - 3.5
Regarding the prognosis of Down syndrome, the following statements are true, except:
A) if there is no serious developmental defect, the lifetime is equal with the average population
B) IQ level is various, but rarely higher than 60
C) women are fertile
D) men are sterile
E) the final height is below 10th percentile of the average population
ANSWER
A) if there is no serious developmental defect, the lifetime is equal with the average population
EXPLANATION
The average age is shorter in the absence of a serious developmental disorder as the connective tissue and vascular system of Down’s syndrome is “aging” faster than average.
PED - 3.6
What is the correct number of the human haploid chromosomes?
A) 22
B) 23
C) 44
D) 46
E) 69
ANSWER
B) 23
EXPLANATION
Haploid refers to the single presence of the chromosome set. There are haploid sets in the gametes. This is the duplicate set in somatic cells in humans, that is, half of the 46 chromosomes, which is 23.
PED - 3.8
These features are characteristic for Edwards syndrome, except for one:
A) severe intrauterine dysmaturity (growth retardation)
B) they are mostly immature and the gestational age is below under 30 weeks
C) finger III is covered by finger II, finger IV is covered by finger V
D) congenital anomaly of the heart
E) only a few survive the 2nd year of life
ANSWER
B) they are mostly immature and the gestational age is below under 30 weeks
EXPLANATION
Edwards syndromic newborns are mature, including a gestational age at 40-41 weeks. In comparison, their birth weight is between 1800 and 2000 g and it is a very pronounced intrauterine growth failure.
PED - 3.10
Children nullsuffering from the following chromosomal abnormalities are not nulllikely to survive, except for one
A) autosomal monosomy
B) X monosomy
C) 21-monosomy
D) triploidy
E) 13-trisomy
ANSWER
B) X monosomy
EXPLANATION
Numeral autosomal abnormalities, with the exception of 21-trisomy, are virtually always non-viable. In contrast, numerical faults in sex chromosomes do not affect or hardly affect life expectancy. Thus, X-monosomy (Ullrich-Turner syndrome) is usually characterized by normal life expectancy. Exceptions to the cases involve vitium
PED - 3.12
What is foetopathy?
A) foetal harm after 13. weeks of gestation
B) foetal harm between 2-13. weeks of gestation
C) it is the consequence of the failure of first cell divisions after fertilization
D) chromosome-related illness of the foetus
ANSWER
A) foetal harm after 13. weeks of gestation
EXPLANATION
In intrauterine life, morphogenesis is divided into three major phases: - blastogenesis (from fertilization to 2nd pregnancy week); - organogenesis (embryonal age, organ formation and differentiation in gestational week 2-13); - phenogenesis (fetal age, further fine differentiation and growth, from the 13th week of pregnancy). Embryopathy occurs between week 2-13, while foetopathy occurs after the 13th week of pregnancy.
PED - 3.13
What would you nullrecommend a healthy second degree cousin couple who want to get married?
A) do not undertake nullpregnancy due to nullhigh genetic risk
B) childbirth can only be undertaken under regular 3-week ultrasound follow-up during pregnancy
C) there is nullhigh risk of foetal chromosome aberration, so chorionic villi sampling is recommended
D) the risk slightly exceeds the average, pregnancy can be nullrecommended
ANSWER
D) the risk slightly exceeds the average, pregnancy can be nullrecommended
EXPLANATION
The proportion of common genes in brothers and sisters and in successive generations is halved. Therefore, in second-degree cousins it is only 1/32, and in their descendants it will be only 1/64. This only slightly increases the risk of recessive and polygenic disorders compared to non-blood relatives.
PED - 3.15
What is not typical of homocystinuria?
A) it is the most common inherited form of amino acid metabolism disorder
B) disturbance of sulphur-containing amino acids
C) patients are mentally retarded
D) luxation of lens can be detected
E) body height exceeds the average
ANSWER
A) it is the most common inherited form of amino acid metabolism disorder
EXPLANATION
Homocystinuria is a characteristic sign, comparable to the Marfan syndrome in many respects, but it is very rare. The neonatal birth rate of the classical form based on cystation synthase deficiency is estimated at 1: 200,000.
PED - 3.16
What is the prevalence of phenylketonuria?
A) 1: 1500
B) 1: 10 000
C) 1: 25 000
D) 1: 70 000
ANSWER
B) 1: 10 000
EXPLANATION
There are minor geographical and ethnic differences in the incidence of phenylketonuria, but in most countries, including Hungary, there is an incidence of 1: 8000 to 1: 10000.
PED - 3.17
What kind of disorder reminds galactosaemia manifesting in the neonatal age?
A) sepsis
B) idiopathic respiratory distress syndrome
C) meconium ileus
D) congenital hypothyroidism
ANSWER
A) sepsis
EXPLANATION
Galactosemia is rarely manifested in neonates, but if this is the case, a clinical picture corresponding to direct hyperbilirubinaemia, hematoma, hepatomegaly, hepatic impairment, hematoma, hypoglycaemia and seizures results in sepsis. Therapy may be deceptive: suspended nutrition and glucose infusions as part of the treatment of sepsis may improve the condition in the debilitating state of the galactose (but the resumption of nutrition may, of course, be fatal).
PED - 3.19
All of these disorders are detectable prenatally, except:
A) arginine-succinic acid disease
B) cystathionine beta synthase deficiency
C) Hunter-syndrome
D) Lesch–Nyhan-syndrome
E) Guillain–Barré-syndrome
ANSWER
E) Guillain–Barré-syndrome
EXPLANATION
Guillain-Barré syndrome is not inherited; it is an acquired illness with ascending paralysis, and is most often a virus infection.
PED - 3.20
What is the inheritance of Duchenne muscular dystrophy?
A) X-linked recessive
B) X-linked dominant
C) autosomal recessive
D) autosomal dominant
E) not inherited, developed postnatally through an autoimmune manner
ANSWER
A) X-linked recessive
EXPLANATION
Duchenne’s disease is inherited by recessive sex (X-chromosome), so half of the children of the transmitting women will be sick. Transmission from father to son excludes this inheritance and diagnosis.
PED - 3.22
Which enzyme defect is responsible for „classic” galactosaemia?
A) galactokinase
B) galactose-1-phosphate uridyltransferase
C) uridyl-diphosphate-galactose-4-epimerase
D) glucose-6-phosphatase
ANSWER
B) galactose-1-phosphate uridyltransferase
EXPLANATION
Galactose-1-phosphate uridyl transferase, in the absence of which galactose-1-phosphate cannot be converted to glucose-1-phosphate
PED - 3.23
Which disease is in the background if the neonatal presentation symptom is meconium ileus?
A) Hirschsprung’s disease
B) congenital hypothyroidism
C) enteritis necrotisans
D) cystic fibrosis (mucoviscidosis)
ANSWER
D) cystic fibrosis (mucoviscidosis)
EXPLANATION
In homozygous individuals in the CFTR (transmembrane regulator) gene, the “thickening” of the excretion of exocrine glands causes pulmonary and gastrointestinal symptoms. In the newborn, the latter may manifest in dense, sticky meconium, which the peristalsis of the infant cannot pass through the intestines, so ileus and perforation can be formed.
PED - 3.25
During infancy an enlarged tongue is characteristic of the disorders listed below, except for one:
A) celiac disease
B) Down syndrome
C) Wiedemann–Beckwith syndrome
D) Hurler disease
E) hypothyroidism
ANSWER
A) celiac disease
EXPLANATION
There is no evidence of an enlarged tongue in celiac disease and visceromegaly is non-characteristic of the disease. Familial incidence of gliadine sensitivity is known, but inheritance is not yet clearly understood. The association of HLA haplotypes (HLA DQ2, HLADQ 8) is justified.
PED - 3.26
Morphogenetic variants (minor anomalies) are the following, except for one:
A) multiple hair whorls
B) hypertelorism
C) mamilla accessoria
D) bifid uvula
E) caput succedaneum
ANSWER
E) caput succedaneum
EXPLANATION
Caput succedaneum is not congenital, but has a slight impairment during delivery. In sites exposed to pressure, this is a local oedema under the scalp, which does not have seams, and is not related to the morphogenesis.
PED - 3.28
Congenital pyloric stenosis is characterised by one of the following:
A) It is often associated with other developmental abnormalities.
B) In mothers toxaemia of pregnancy is frequently present.
C) Autosomal recessive inheritance is present in the affected girls.
D) The prevalence is the same among boys and girls due to maternal smoking.
E) Boys are more frequently affected with multifactorial (polygenic) inheritance.
ANSWER
E) Boys are more frequently affected with multifactorial (polygenic) inheritance.
EXPLANATION
Pylorus stenosis in the boy: girl ratio is around 5: 1-6: 1. This also means that if a less susceptible daughter develops the disease, the risk of repetition is greater (“non-affected heredity”) in the succeeding brothers.
PED - 3.30
How can we prevent the development of spina bifida/anencephaly?
A) The use of contraceptives must be halted to be finished at least half a year before prior to the planned conceiving.
B) At the time of conceiving you must be attentive in the care of optimal maternal folic acid intake.
C) During the first trimester, the mother should consume at least 250 mg of vitamin C daily.
D) The mother should follow a low cholesterol diet.
ANSWER
B) At the time of conceiving you must be attentive in the care of optimal maternal folic acid intake.
EXPLANATION
Providing adequate maternal folic acid is a good example of primary prevention. In addition to blocking occlusion errors, it may also play a role in reducing other developmental defects (liposuction, palate, cardiac defects).
PED - 3.34
It is characteristic of inheritance of mitochondrial diseases:
A) the mother is the transmitter
B) only the father can be the transmitter
C) the mother and the father could transmit the disease, but mainly it manifests in girls
D) gender does not influence the inheritance
ANSWER
A) the mother is the transmitter
EXPLANATION
Only the mother can be the transporter, because in the oocyte of the gametes there are mitochondria, and in the sperm, virtually none. They lose their function during fertilization.
PED - 3.35
Mutations of mitochondrial DNA can cause a disease mostly of the following organs, except for one:
A) Central nervous system
B) Muscles, connective tissue
C) Bone marrow
D) Liver
E) Heart and blood vessels
ANSWER
C) Bone marrow
EXPLANATION
Mutations of mitochondrial DNA generally exhibit a variety of manifestations. The organs of haematopoiesis are rarely or only secondarily affected.
PED - 3.36
Characteristic for teratogenic effects:
A) The onset of the defect is immediately after the fertilization
B) The injury depends on both the type of effect and time of it
C) The consequences of the teratogenic effects are more severe in mothers older than 35 years
D) The same teratogenic effect may have variable manifestations in different ethnic groups
ANSWER
B) The injury depends on both the type of effect and time of it
EXPLANATION
The quality of the maleficence of the teratogen can be crucial: certain noxae and reagents, for example, are likely to have a specific effect on the differentiation of given organs. The time of the effect is also important: certain developmental disorders only develop in specific stages of the differentiation.
PED - 3.37
A newborn is presented with intrauterine atrophy, difficulties in feeding, developmental delay, muscle hypotonia, short palpebral fissure, snub nose, hypoplastic maxilla and flat philtrum. These signs are suspicious for:
A) Mosaic Down syndrome
B) Phenylketonuria
C) Fetal alcohol syndrome
D) Fetal hydantoin syndrome
E) Congenital rubella syndrome
ANSWER
C) Fetal alcohol syndrome
EXPLANATION
The symptoms listed in the question are textbook examples of foetal alcohol syndrome. It needs to point out, however, in which the clinical picture is often poor, only several symptoms manifest, and given the nature of the syndrome, history taking can be deceptive, largely due to the involved mothers mostly deny alcohol consumption. Based on published literature, the development of foetal alcohol syndrome can be expected in the chronic consumption of the equivalent of 80g pure alcohol a day, with significant individual variation.
PED - 3.39
One of the following viral infections during pregnancy can result in developmental malformation in the fetus:
A) Parotitis epidemic
B) Influenza A2
C) Hepatitis A
D) Hepatitis B
E) Varicella
ANSWER
E) Varicella
EXPLANATION
95-98% of mothers have an immunity to varicella due to their childhood contraction of the disease. If a pregnant mother contacts varicella, the gravidity may result in a spontaneous abortion, or, in some cases, foetal damage can develop: limb deformity, shortening of limbs, microcephaly, hydrocephaly, microphthalmy, cataract, chorioretinitis, extensive and deep scars on the skin’s surface. Since these rarely occur, most geneticists do not recommend termination. Varicella towards the end of the gravidity can lead to inflammatory disorders in the foetus, of which varicella pneumonia is the most severe.
