Classic Presentations part 1

Question 1

Gout, intellectual disability, self mutilating behavior in a boy

Answer 1

Lesch-Nyhan syndrome (HGPRT deficiency, X-linked recessive)

Question 2

Situs inversus, chronic sinusitis, bronchiectasis, infertility

Answer 2

Kartagener syndrome (dynein arm defect affecting cilia)

Question 3

Blue sclera

Answer 3

Osteogenesis imperfecta (type I collagen defect)

Question 4

Elastic skin, hypermobility of joints, increased bleeding tendency

Answer 4

Ehlers-Danlos syndrome (type V collagen defect, type III collagen defect seen in vascular type)

Question 5

Arachnodactyly, lens dislocation (upward and temporal), aortic dissection, hyperflexible joints

Answer 5

Marfan syndrome (fibrillin defect)

Question 6

Café-au-lait spots (unilateral), polyostotic fibrous dysplasia, precocious puberty, multiple endocrine abnormalities

Answer 6

McCune-Albright syndrome (Gs protein activating mutation)

Question 7

Calf pseudohypertrophy

Answer 7

Muscular dystrophy (most commonly Duchenne, due to X linked recessive frameshift mutation of dystrophin gene)

Question 8

Child uses arms to stand up from squat

Answer 8

Duchenne muscular dystrophy (Gowers sign)

Question 9

Slow, progressive muscle weakness in boys

Answer 9

Becker muscular dystrophy (X linked non-frameshift deletions in dystrophin; less severe than DMD)

Question 10

Infant with cleft lip/palate, microcephaly or holoprosencephaly, polydactyly, cutis aplasia

Answer 10

Patau syndrome (trisomy 13)

Question 11

Infant with microcephaly, rocker-bottom feet, clenched hands, low set ears, and structural heart defect

Answer 11

Edwards syndrome (trisomy 18)

Question 12

Single palmar crease

Answer 12

Down syndrome (trisomy 21)

Question 13

Dilated cardiomyopathy, edema, alcoholism or malnutrition

Answer 13

Wet beriberi (thiamine [vit B1] deficiency)

Question 14

Dermatitis, dementia, diarrhea

Answer 14

Pellagra (niacin [vit. B3] deficiency)

Question 15

Swollen gums, mucosal bleeding, poor wound healing, petechiae

Answer 15

Scurvy (vit. C deficiency; can’t hydroxylate proline/lysine for collagen synthesis)

Question 16

Chronic exercise intolerance with myalgia, fatigue, painful cramps, myoglobinuria)

Answer 16

McArdle disease (skeletal muscle glycogen phosphorylase deficiency)

Question 17

Infant with hypoglycemia, hepatomegaly

Answer 17

Cori disease (debranching enzyme deficiency) or Von Gierke disease (glucose-6-phosphatase deficiency, more severe)

Question 18

Myopathy (infantile hypertrophic cardiomyopathy), exercise intolerance

Answer 18

Pompe disease (lysosomal α-1,4-glucosidase deficiency)

Question 19

Cherry-red spots on macula

Answer 19

Tay-sachs (ganglioside accumulation) or Niemman-Pick (sphingomyelin accumulation), central retinal artery occlusion

Question 20

Hepatosplenomegaly, pancytopenia, osteoporosis, avascular necrosis of femoral head, bone crises

Answer 20

Gaucher disease (glucocerebrosidase [β-glucosidase] deficiency)

Question 21

Achilles tendon xanthoma

Answer 21

Familial hypercholesterolemia (decreased LDL receptor signaling)

Question 22

Anaphylaxis following blood transfusion

Answer 22

IgA deficiency

Question 23

Male child, recurrent infections, no mature B cells

Answer 23

Bruton disease (X-linked agammaglobulinemia)

Question 24

Recurrent cold (non-inflamed) abscesses, eczema, high serum IgE, increased eosinophils

Answer 24

Hyper-IgE syndrome