Biochemistry

Question 1

intellectual disability, self-mutilations, aggression, hyperuricemia, gout, dystonia, macrocytosis

Answer 1

Lesch-Nyhan syndrome

Question 2

dry skin, photosensitivity, skin cancer

Answer 2

xeroderma pigmentosum

Question 3

hypotonia, seizures, jaundice, craniofacial dysmorphia, hepatomegaly, early death, PEX mutation

Answer 3

Zellweger syndrome

Question 4

scaly skin, ataxia, cataracts/night blindiness, shortening of the 4th toe, epiphyseal dysplasia

Answer 4

Refsum disease

Question 5

VLCFA buildup in adrenal glands, white matter, and testes

Answer 5

Adrenoleukodystrophy

Question 6

situs inversus, hearing loss, sinusitis, ear infections, bronchiectasis, infertility, increased risk of ectopic pregnancy, decreased nasal nitric oxide

Answer 6

Primary ciliary dyskinesia

Question 7

multiple bone deformities, blue sclerae, tooth abnormalities, conductive hearing loss

Answer 7

Osteogenesis imperfecta

Question 8

hyperextensible skin, hypermobile joints, joint dislocation, berry and aortic aneurysms, organ rupture, gravid uterus

Answer 8

Ehler’s-Danlos syndrome

Question 9

brittle hair, growth and developmental delay, hypotonia, increased risk of cerebral aneurysms

Answer 9

Menkes disease

Question 10

long extremities, chest wall deformity, hypermobile joints, long fingers and toes, cystic medial necrosis of the aorta, aortic root aneurysm / rupture / dissection, mitral valve prolapse, increased risk of spontaneous pneumothorax

Answer 10

Marfan syndrome

Question 11

pectus deformity, tall stature, increased arm:height ratio, decreased upper:lower body segment ratio, arachnodactly, joint hyperlaxity, skin hyperelasticity, scoliosis

Answer 11

Homocystinuria

Question 12

unilateral cafe-au-lait spots with ragged edges, polyostotic fibrous dysplasia, at least one endocrinopathy

Answer 12

McCune-Albright syndrome

Question 13

hyperphagia, obesity, intellectual disability, hypogonadism, hypotonia

Answer 13

Prader-Willi

Question 14

seizures, ataxia, severe intellectual disability, inappropriate laughter

Answer 14

Angelman syndrome

Question 15

recurrent pulmonary infections, allergic bronchopulonary aspergillosis, chronic bronchitis and bronchiectasis, reticulonodular pattern on CXR, opacification of sinuses, nasal polyps, nail clubbing, pancreatic insufficiency, malabsorption with steatorrhea, fat soluble vitamin [A. D. E. K.] deficiencies, meconium ileus in newborns, infertility in males, subfertility in females

Answer 15

cystic fibrosis

Question 16

muscle weakness starting from pelvic girdle and progressing superiorly, pseudohypertrophy of calf muscles, waddling gait, onset before 5 years of age, increased risk of dilated cardiomyopathy, gower’s sign

Answer 16

Duchenne muscular dystrophy

Question 17

muscle weakness starting from pelvic girdle and progressing superiorly, pseudohypertrophy of calf muscles, waddling gait, onset before 5 years of age, increased risk of dilated cardiomyopathy, gower’s sign

less severe due to non-frameshift mutation

Answer 17

Becker muscular dystrophy

Question 18

myotonia, muscle wasting, cataracts, testicular atrophy, frontal balding, arrhythmia

Answer 18

Myotonic dystrophy

Question 19

mitochondrial encephalomyopathy with lactic acidosis and strokelike episodes

Answer 19

MELAS

Question 20

myoclonic epilepsy with ragged red fibers

Answer 20

MERRF

Question 21

myoclonic epilepsy with ragged red fibers

Answer 21

MERRF

Question 22

neuronal death of the retina and optic nerve, subacute bilateral vision loss in teens/young adults/ usually permanent, possibly tremors, multiple sclerosis-like illness

Answer 22

Leber hereditary optic neuropathy

Question 23

females between age 1-4, regression in motor, verbal, and cognitive abilities, ataxia, seizures, growth deceleration, and stereotyped hand-wringing

Answer 23

Rett syndrome

Question 24

tremor, ataxia, primary ovarian insufficiency, postpubertal macroorchidism, long face with long jaw, large everted ears, autism, mitral valve prolapse, hypermobile joints, self mutation, CGG trinucleotide repeat

Answer 24

Fragile X syndrome

Question 25

CAC trinucleotide repeats

Answer 25

Huntington disease

Question 26

CTG trinucleotide repeats

Answer 26

Myotonic dystrophy

Question 27

GAA trinucleotide repeat

Answer 27

Friedrich ataxia

Question 28

intellectual disability, flat facies, prominent epicanthal folds, single palmar crease, incurved 5th finger, gap between 1st and second toes, duodenal atresia, hirschprung disease, congenital heart disease, Brushfield spots, early onset alzheimer's, increased risk of AML/ALL

Answer 28

Down's syndrome

Question 29

prominent occiput, rocker-bottom feet, intellectual disability, nondisjunction, clenched fists with overlapping fingers, low set ears, micrognathia, congenital heart disease, omphalocele, myelomeningocele, death by age 1

Answer 29

Edwards syndrome

Question 30

severe intellectual disability, rocker-bottom feet, microopthalmia, microcephaly, cleft lip/palate, holoprosencephaly, polydactly, cutis aplasia, congenital heart (pump) disease, polycystic kidney disease, omphalocele, death occurs by age 1

Answer 30

Patau syndrome

Question 31

microcephaly, moderate to severe intellectual disability, high pitched crying, epicanthal folds, cardiac abnormalities [ventricular septal defect]

Answer 31

Cri-du-chat syndrome

Question 32

elfin facies, intellectual disability, hypercalcemia, well developed verbal skills, extreme friendliness with strangers, cardiovascular problems [supravalvular aortic stenosis, renal artery stenosis]

Answer 32

Williams syndrome

Question 33

night blindness, dry scaly skin, dry eyes, conjunctival squamous metaplasia, bitot spots, corneal degeneration, immunosuppression

Answer 33

Vitamin A deficiency

Question 34

confusion, opthalmoplegia, nystagmus, ataxia

Answer 34

Wenicke encephalopathy

Question 35

amenstic, confabulations, personality changes, permanent memory loss, B1 deficiency

Answer 35

Korsakoff syndrome

Question 36

confusion, opthalmoplegia, nystagmus, ataxia, confabulations, personalty changes, memory loss, damage of medial dorsal nucleus of the thalamus

Answer 36

Wernicke-Korsakoff syndrome

Question 37

polyneuropathy, symmetric muscle wasting, B1 deficiency

Answer 37

Dry beriberi

Question 38

High output cardiac failure due to systemic vasodilation, B1 deficiency

Answer 38

Wet beriberi

Question 39

cheilosis [inflammation of the lips, scaling and fissures at the corners of the mouth] mangenta tongue, corneal vascularization

Answer 39

Vitamin B2 deficiency

Question 40

glossitis, pellagra, malignant carcinoid syndrome, diarrhea, dementia, dermatitis, hyperpigmentation of sun exposed limgs

Answer 40

Vitamin B3 deficiency

Question 41

dermatitis, enteritis, alopecia, adrenal insufficiency leading to burning sensation of the feet

Answer 41

Vitamin B5 deficiency

Question 42

convulsions, hyperirritability, peripheral neuropathy, sideroblastic anemia

Answer 42

Vitamin B6 deficiency

Question 43

Dermatitis, enteritis, alopecia, caused by long term antibiotic use

Answer 43

Vitamin B7 deficiency

Question 44

macrocytic, megaloblastic anemia, glossitis, increased homocysteine, normal methylmalonic acid

Answer 44

Vitamin B9 deficiency

Question 45

macrocytic, megaloblastic anemia, hypersegmented polymorphonuclear cells, subacute combined degeneration of the dorsal columns, lateral corticospinal tracts, and spinocerebellar tracts, increased homocysteine and methylmalonic acid, secondary folate deficiency

Answer 45

Vitamin B12 deficiency

Question 46

swollen gums, easy bruising, petechiae, hemarthrosis, anemia, poor wound healing, perifollicular and subperiosteal hemorrhages, corkscrew hair, weakened immune response

Answer 46

Vitamin C deficiency

Question 47

bone deformity, osteomalacia in adults, hypocalcemic tetany

Answer 47

Vitamin D deficiency

Question 48

hemolytic anemia, acanthocytosis, muscle weakness, demyelination of posterior columns and spinocerebellar tract

Answer 48

Vitamin E deficiency

Question 49

neonatal hemorrhage with increased PT and aPTT, normal bleeding time, after prolonged use of broad spectrum antibiotics

Answer 49

Vitamin K deficiency

Question 50

delayed wound healing, suppressed immunity, male hypogonadism, decreased adult hair [axillary, facial, pubic], dysgeusia, anosmia, associated with acrodermatitis enteropathica, may predispose to alcoholic cirrhosis

Answer 50

Zinc deficiency

Question 51

malnutrition, edema, anemia, fatty liver, skin lesions [hyperkeratosis, dyspigmentation]

Answer 51

Kwashiorkor

Question 52

malnutrition without edema, muscle wasting

Answer 52

Marasmus

Question 53

neurologic defects, lactic acidosis, increased serum alanine starting in infancy

Answer 53

Pyruvate dehydrogenase complex deficiency

Question 54

fava beans, sulfonamides, nitrofurantoin, primaquine/chloroquine/antituberulosis drugs, infection, precipitates hemolysis, X-linked recessive, sub-Saharan Africa, Southeast Asia, heinz bodies, bite cells

Answer 54

Glucose-6-phosphate dehydrogenase deficiency

Question 55

fructose in blood and urine

Answer 55

Essential fructosuria

Question 56

hypoglycemia, jaundice, cirrhosis, and vomiting following consumption of fruit, juice, or honey

Answer 56

Hereditary fructose intolerance

Question 57

galactosemia and galactosuria, infantile cataracts

Answer 57

Galactokinase deficiency

Question 58

failure to thirve, jaundice, hepatomegaly, infantile cataracts, intellectual disability, begins when an infant starts to feed

Answer 58

Classic galactosemia

Question 59

cataracts, retinopathy, peirpheral neuropathy

Answer 59

Aldose reductase deficiency

Question 60

Bloating, cramps, flatulence, osmotic diarrhea

Answer 60

Lactase deficiency

Question 61

flapping tremor [asterixis], slurring of speech, somnolence, vomiting, cerebral edema, blurring of vision, increased ammonia, decreased GABA, decreased a-ketoglutarate

Answer 61

hyperammonemia

Question 62

increased orotic acid in the blood and urine, decreased BUN, symptoms of hyperammonemia

Answer 62

Orinthine transcarbamylase deficiency

Question 63

intellectual disabillity, microcephaly, seizures, hypopigmented skin, eczema, musty body odor

Answer 63

Phenylketonuria

Question 64

vomiting, poor feeding, urine smelling like maple syrup/burnt sugar, progressive neurological decline

Answer 64

Maple syrup urine disease

Question 65

bluish-black connective tissue, ear cartilage, sclerae, urine turns black on prolonged exposure to air, may have debilitating arthralgias

Answer 65

Alkaptonuria

Question 66

osteoporosis, marfanoid habitus, ocular changes, thrombosis and atherosclerosis leading to stroke and MI, kyphosis, intellectual disability, hypopigmented skin, increased homocysteine in urine

Answer 66

Homocystinuria

Question 67

hexagonal cystine stones

Answer 67

Cystinuria

Question 68

poor feeding, vomiting, hypotonia, high anion gap metabolic acidosis, hepatomegaly, seizures, decreased propionyl-CoA, decreased methylmalonic acid

Answer 68

Propionic acidemia

Question 69

poor feeding, vomiting, hypotonia, high anion gap metabolic acidosis, hepatomegaly, seizures, deficiency of methylmalonyl-CoA mutase or vitamin B12

Answer 69

Methylmalonic acidemia

Question 70

severe fasting hypoglycemia, increased glycogen in the liver and kidneys, increased blood lactate, increased triglycerides, increased uric acid [gout], hepatomegaly, renomegaly

Answer 70

Von Gierke disease

Question 71

cardiomyopathy, hypotonia, exercise intolerance, enlarged tongue, systemic findings leading to early death

Answer 71

Pompe disease

Question 72

Cardiomyopathy, hypotonia, exercise intolerance, enlarged tongue, systemic findings leading to early death, not as severe, normal blood lactate

Answer 72

Cori disease

Question 73

hepatosplenomegaly, failure to thrive in early infancy, infantile cirrhosis, muscular weakness, hypotonia, cardiomyopathy, early childhood death

Answer 73

Andersen disease

Question 74

painful muscle cramps, myoglobinuria with strenuous exercise, arrhythmia from electrolyte abnormalities, second wind phenomenon

Answer 74

McArdle disease

Question 75

progressive neurodegeneration, developmental delay, hyperreflexia, hyperacusis, cherry red spot on macula, lysosomes with onion skin

Answer 75

Tay-Sachs disease

Question 76

episodic neuropathy, angiokeratomas, hypohidrosis, progressive renal failure, cardiovascular disease

Answer 76

Fabry disease

Question 77

Central and peripheral demyelination with ataxia and demenita

Answer 77

Metachromatic leukodystrophy

Question 78

Peripheral neuropathy, destruction of oligodendrocytes, developmental delay, optic atrophy, globoid cells

Answer 78

Krabbe disease

Question 79

hepatosplenomegaly, pancytopenia, osteoporosis, avascular necrosis of the femur, bone crises, Gaucher cells

Answer 79

Gaucher disease

Question 80

Progressive neurodegeneration, hepatosplenomegaly, foam cells, cherry red spot on the macula

Answer 80

Niemann-Pick disease

Question 81

developmental delay, skeletal abnormalities, airway obstruction, corneal clouding, hepatosplenomegaly

Answer 81

Hurler syndrome

Question 82

Mild Hurler syndrome and aggressive behavior, no corneal clouding

Answer 82

Hunter syndrome

Question 83

weakness, hypotonia, hypoketotic hypoglycemia, dilated cardiomyopathy

Answer 83

Systemic 1* carnitine deficiency

Question 84

vomiting, lethargy, seizures, coma, liver dysfunction, hyperammonemia, can lead to sudden death in infants or children

Answer 84

Medium-chain acyl-CoA dehydrogenase deficiency

Question 85

severe fat malabsorption, steatorrhea, failure to thirve, later manifesting retinitis pigmentosa, spinocerebellar degeneration due to vitamin E deficiency, progressive ataxia, acanthocytosis, lipid-laden enterocytes

Answer 85

Abetalipoproteinemia

Question 86

pancreatitis, hepatosplenomegaly, eruptive/pruritic xanthomas, creamy layer in supernatant

Answer 86

Familial dyslipidemia type I hyperchlomicronemia

Question 87

accelerated atherosclerosis [MI before age 20], tendon [achilles] xanthomas, corneal arcus

Answer 87

Familial dyslipidemias type II hypercholesterolemia

Question 88

Premature atherosclerosis, tuberoeruptive and palmar xanthomas

Answer 88

Familial dyslipidemias type III dysbetalipoproteinemia

Question 89

Hypertriglyceridemia >1000 mg/dL, can cause acute pancreatitis, related to insulin resistance

Answer 89

Familial dyslipidemias type IV hypertriglyceridemia

Question 90

Familial dyslipidemias type II hypercholesterolemia

Answer 90

accelerated atherosclerosis [MI before age 20], tendon [achilles] xanthomas, corneal arcus

Question 91

Familial dyslipidemias type III dysbetalipoproteinemia

Answer 91

Premature atherosclerosis, tuberoeruptive and palmar xanthomas

Question 92

Familial dyslipidemias type IV hypertriglyceridemia

Answer 92

Hypertriglyceridemia >1000 mg/dL, can cause acute pancreatitis, related to insulin resistance