Nutrition

Question 1

How can you calculate a patient’s daily caloric requirement?

Answer 1

Holliday-Segar formula:

100 kcal/kg for first 10 kg + 50 kcal/kg for next 10 kg + 20 kcal/kg for remainder

Question 2

Describe clinical features of mild dehydration

Answer 2

• dry mucous membranes, oliguria
• 5% weight loss
• 50 ml/kg fluid deficit

Question 3

Describe clinical features of moderate dehydration

Answer 3

• marked oliguria, poor skin turgor, sunken fontanelle, tachycardia, irritability
• 10% weight loss
• 100 ml/kg fluid deficit

Question 4

Describe clinical features of severe dehydration

Answer 4

• hypotension, poor perfusion, lethargy
• 15% weight loss
• 150 cc/kg fluid deficit

Question 5

What are the clinical benefits of breastfeeding?

Answer 5

decreased incidence of:

• septicemia
• acute and recurrent otitis media
• diarrhea
• necrotizing enterocolitis,
• UTIs
• protection against childhood obesity and asthma

Question 6

What needs to be done to breastmilk for preterm infants at 1 mo of age?

Answer 6

• fortification because their nutritional needs surpass the minerals and electrolytes they need

Question 7

What are the contraindications to breastfeeding?

Answer 7

• maternal HIV infection
• child w/ galactosemia (intolerant of breast milk)
• mother on isotretinoin therapy
• temporary cessation s/p mother getting technetium-99m contrast
• mothers of child w/ G6PD deficiency will need to avoid trigger foods/drugs

Question 8

Who should NOT get soy formula?

Answer 8

• preterm infants
• NOT beneficial in preventing/managing colic

Question 9

Who should get soy formula?

Answer 9

• vegetarian babies
• babies w/ galactosemia

Question 10

What are common syndromes/disease that have autosomal dominant inheritance pattern?

Answer 10

• Alagille syndrome
• Achondroplasia
• Osteogenesis Imperfecta
• CHARGE syndrome
• Neurofibromatosis Type I (NF1)
• Marfan syndrome
• Most familial cancer syndromes

Question 11

What should you suspect if an apparently normal parent has multiple children affected with the same autosomal dominant condition?

Answer 11

germline mosaicism:

• individuals with the germline mosaicism do not show signs of the disease because parent carries the gene mutation in gonadal tissue and germline cells but not somatic cells
• offspring are at increased risk to inherit the condition

Question 12

What are common syndromes that are inherited in an autosomal recessive pattern?

Answer 12

• Cystic Fibrosis
• Hemoglobinopathies
• most inborn errors of metabolism

Question 13

What patterns on a pedigree are consistent w/ AR pattern?

Answer 13

• skipping generations
• males and females equally affected
• males and females can each transmit the altered allele
• risk for 2 heterozygotes to have an affected offspring = 25%
• consanguinity increases the risk of having an AR disorders

Question 14

What patterns on a pedigree suggest AD inheritance?

Answer 14

• both sexes equally affected
• both sexes transmit to offspring
• present in all generations
• every affected child has a parent with the disorder
• any affected individual has a 50% chance of passing it on to offspring
• fathers can transmit to sons

Question 15

What are common disorders/syndromes inherited in an X-linked pattern?

Answer 15

• Hemophilia A
• Duchenne and Becker muscular dystrophy
• red-green color blindness

Question 16

What are clinical features of Duchenne muscular dystrophy?

Answer 16

XR inheritance pattern

• progressive muscle weakness: starts w/ gluteal, pelvic, and girdle muscles. will have delayed motor milestones
• calf hypertrophy
• Gowers sign (~2 yo)
• wheelchair dependency by 12 years old
• cardiomyopathy
• respiratory failure
• cognitiv delays

Question 17

What patterns on pedigree are consistent with X-linked recessive inheritance?

Answer 17

• never male-to-male transmission
• if a generation only has females, will look like the disease “skipped” a generation
• affected father transmits the disease allele to all his daughters but none of his sons
• carrier females have 50% chance of transmission to sons

Question 18

What is genomic imprinting?

Answer 18

• differences in gene expression that depend on whether the disease allele is inherited from the mother or father
• ex: Chromosome 15 deletion:
  
  • Prader willi (father)
  • Angelman (mother)

Question 19

What are clinical features of Prader-Willi syndrome (chrom 15 deletion)?

Answer 19

• infancy:
  
  • severe hypotonia at birth
  • feeding difficulties
  • narrow forehead
  • almond-shaped eyes
• childhood
  
  • hyperphagia (severe obesity)
  • short stature
  • small hands/feet
  • hypogonadism
  • mild ID
  • behavior disorders

Question 20

What are clinical features of Angelman Syndrome (chrom 15 deletion)?

Answer 20

• appear normal at birth, but with time:
  
  • seizures
  • severe ID
  • microcephaly
  • ataxia
  • hand-flapping
  • outbursts of laughter
  • “puppet-like” gait

Question 21

Describe inheritance of mitochondrial disorders

Answer 21

zygote receives all mitochondria from the ovum (mother), so:

• mother carrying mtDNA mutation passes it to ALL offspring
• father carrying mtDNA mutation passes it to NO offspring

Question 22

What are common diseases/syndromes caused by mitochondrial mutations?

Answer 22

• myoclonic epilepsy and ragged red fibers (MERRF)
• mitochondrial encephalopathy, lactic acidosis, and stroke-like episodes (MELAS)
• Leigh syndrome
• Kearns- Sayre syndrome
• Pearson syndrome

Question 23

What are common trinucleotide repeat diseases?

Answer 23

• Fragile X Syndrome (CGG repeat → anticipation aka increased severity with transmission); X-linked
• Myotonic Dystrophy (CTG repeat); AD

Question 24

Describe clinical features of Fragile X Syndrome

Answer 24

• ID (most common inherited ID syndrome)
• large head
• long face w/ prominent jaw and large ears
• large hands/feet
• macroorchidism after puberty
• hyperextensible joints

Question 25

What are clinical features of myotonic dystrophy?

Answer 25

AD, anticipation

• myotonia w/ progressive weakness and wasting - distal muscles affected more than proximal, myotonia on grip testing (good grip but can’t let go)
• cataracts
• testicular atrophy
• diabetes mellitus
• ID
• premature balding
• cardiac conduction abnormalities

congenital myotonic dystrophy: marked hypotonia, ID, neonatal resp distress, feeding difficulties, talipes