Deck VI

Question 1

When does intraventricular hemorrhage in premature newborns most commonly occur?

Answer 1

Within the first 5 postnatal days.

Question 2

How does IVH present in a newborn?

Answer 2

It can be clinically silent or present with an altered level of consciousness, hypotonia, decreased spontaneous movements or with symptoms of catastrophic bleeding (bulging anterior fontanells, hypotension, decerebate posturing, tonic-clonic seizures, irregular respirations, coma)

Question 3

From where does IVH in preterm infants usually originate?

Answer 3

In the germinal matrix, a highly cellular and vascularized layer in the subventricular zone from which neurons and glial cells migrate out during brain development.

Question 4

What fine motor skills are expected of an infant 3 years of age?

Answer 4

The child should be able to copy a circle and use utensils.

Question 5

At age three, what are five milestones that a child should have met?

Answer 5

To play in parallel, speak in simple sentances, copy a circle, use utensils, ride a tricycle.

Question 6

What visual defect is caused by lesions to the optic tract?

Answer 6

Contralateral homonymous hemianopia.

Question 7

What is the preferred treatment for narcolepsy?

Answer 7

Agents that promote wakefullness- psychostimulants. Modafinil is a non-amphetamine psychostimulant that is first line; amphetamines are second line agents.

Question 8

What is the pathophysiology of narcolepsy?

Answer 8

Low levels of the NT orexin (hypocretin).

Question 9

What is the classic triad of symptoms in congenital toxoplasmosis?

Answer 9

Hydrocephalus, intracranial calcifications, chorioretinitis.

Question 10

What is chorioretinitis?

Answer 10

Inflammation of the choroids and the retina that may leave cotton like white/yellow scars on the retina that are visible on funduscopy.

Question 11

What should expectant mothers avoid to prevent exposure to Toxoplasma?

Answer 11

Cat feces.

Question 12

How does tetrodotoxin (from pufferfish) cause toxicity?

Answer 12

By binding to voltage gated sodium channels in nerve and cardiac tissue to prevent sodium influx and depolarization.

Question 13

Short acting benzodiazapines are preferred over long acting drugs in what patient population?

Answer 13

Patients with advanced liver dysfunction.

Question 14

How does morphine interact with opioid pathways to modulate morphine tolerance?

Answer 14

Via the neurotransmitter glutamate.

Question 15

How does the optic nerve respond to light when it is damaged?

Answer 15

Light to the damaged eye will cause neither pupil to constrict; light to the contralateral (undamaged) eye will cause both pupils to constrict.

Question 16

What causes polyhydraminos?

Answer 16

Decreased fetal swallowing or increased fetal urination.

Question 17

Which fetal anomalies may lead to decreased swallowing and polyhydraminos?

Answer 17

GI obstruction (duodenal, espohageal, intestinal atresia) and anencephaly

Question 18

What fetal anomalies may lead to increased fetal urination?

Answer 18

High cardiac output due to anemai or twin-twin transfusion syndrome

Question 19

What drugs are used to treat myasthenia gravis?

Answer 19

Cholinesterase inhibitors (physostigmine, neostigmine, pyridostigmine)

Question 20

When does edrophonium produce improvement in patients with myasthenia gravis?

Answer 20

When the patient is undertreated (i.e. suboptimal doses of medication), not when patient is in cholinergic crisis (when too much acetylcholine causes muscles to be refractory to future impulses)

Question 21

What symptoms indicate a urea cycle disorder?

Answer 21

Neurological damage with elevated serum ammonia levels.

Question 22

What is the most common urea cycle disorder?

Answer 22

Ornithine transcarbamoylase deficiency.

Question 23

What is increased in the urine of patients with an ornithine transcarbamoylase deficiency?

Answer 23

Increased urine orotic acid.

Question 24

A positive Trendelenburg sign indicates damage to which nerve?

Answer 24

Superior Gluteal.

Question 25

Defects in what type of reaction lead to development of methylmalonic acedemia (acudiura)?

Answer 25

Isomerization reaction of methymalonyl CoA to succinyl CoA, prior to succinyl CoA entering the TCA cycle.

Question 26

What deficiency is present in Tay Sachs disease and what abnormal accumulation results?

Answer 26

Deficiency in b-hexosaminidase A; accumulation of GM2 Ganglioside

Question 27

What is akathisia?

Answer 27

Subjective restlessness with inability to sit still; it typically presents days to weeks after initiating antipsychotic treatment.

Question 28

What clinical features are associated with PCP abuse?

Answer 28

PCP is a hallucinogen causing violent behaviour, dissociation, hallucinations, amnesua, nystagmus, ataxia, memory loss.

Question 29

What immature defense mechanism substitutes imaginary, less disturbing scenarios to avoid awareness of painful feelings?

Answer 29

Fantasy.

Question 30

What types of intracellular connections mediate the BBB between the endothelial cells of CNS capillaries?

Answer 30

Tight junctions (also known as zona occludens).