Nervous System IV

Question 1

Toxoplasma gondii is the most common CNS infection in ____

Answer 1

Toxoplasma gondii is the most common CNS infection in HIV patients not receiving HAART

Question 2

____ are seen on CT/MRI in patients with T. gondii infection

Answer 2

multiple CNS abscess-like ring-enhanced structures are seen on CT/MRI in patients with T. gondii infection

Question 3

____ are the infective form of T. gondii

Answer 3

oocysts are the infective form of T. gondii

Question 4

list the findings that suggest T. gondii diagnosis

Answer 4

CD4 count < 100

compatible clinical syndrome

positive T. gondii IgG antibody

brain imaging with ring-enhancing lesions

Question 5

describe Botulism and Tetanus

Answer 5

Question 6

Botulinum toxin binds to ____ blocking ____

Answer 6

Botulinum toxin binds to presynaptic cholinergic nerve terminals blocking release of ACh

Question 7

Tetanospasmin binds to ____, is internalized, and transported ____ and ultimately blocks ____

Answer 7

Tetanospasmin binds to presynaptic membrane of the NMJ, is internalized, and transported retroaxonally to the spinal cord and ultimately blocks release of glycine and GABA

Question 8

Botulism is associated with ___ paralysis, ____ and ____

while

Tetanus is associated with ____ paralysis

Answer 8

Botulism is associated with flaccid paralysis, ptosis and slurred speech

while

Tetanus is associated with spastic/rigid paralysis

Question 9

describe the pathogenesis of Cladophialphora bantiana

Answer 9

Question 10

Cladophilaphora bantiana has a ____ coloration due to presence of _____

Answer 10

Cladophilaphora bantiana has a golden-brown coloration due to presence of melanin pigment in spores and cell wall

Question 11

Mycobacterium leprae causes damage to ____ by invading ____

Answer 11

Mycobacterium leprae causes damage to peripheral sensory nerves by invading Schwann cells, directly causing demyelination

Question 12

the main feature of M. leprae is _____ lesions with/without which 3 symptoms?

Answer 12

the main feature of M. leprae is hypopigmented skin lesions with/without:

hypoesthesia

weakness

peripheral nerve thickening

Question 13

list the top causes of bacterial conjunctivitis

Answer 13

S. aureus (adults)

S. pneumoniae

H. influenzae

M. catarrhalis

Question 14

Adenovirus can cause epidemic _____, which leads to watery, non-purulent discharge from eyes

Answer 14

Adenovirus can cause epidemic keratoconjunctivitis (EKC), which leads to watery, non-purulent discharge from eyes

Question 15

viral conjunctivitis is described as a ____ sensation

Answer 15

viral conjunctivitis is described as a “gritty” sensation

Question 16

____ is a major cause of preventable blindness

Answer 16

C. trachomatis is a major cause of preventable blindness

Question 17

Trachoma (C. trachomatis) is caused by which serovars?

Answer 17

A, B, Ba and C

(D - K cause chlamydia)

Question 18

describe the 2 phases of Trachoma

Answer 18

• active trachoma:
  
  • young children
  • mild, self-limited follicular conjunctivitis
• cicatricial disease and blindness:
  
  • adults
  • repeated infection leads to conjunctival inflammation and eyelid scarring
  • ingrown eyelashes lead to edema, ulceration and scarring

Question 19

describe preseptal and postseptal (orbital) cellulitis

Answer 19

Question 20

describe the etiologies of preseptal vs. postseptal cellulitis

Answer 20

Question 21

preseptal cellulitis results from ____

Answer 21

preseptal cellulitis results from external ocular infection or skin break

Question 22

postseptal cellulitis results from ____

Answer 22

postseptal cellulitis results from extension of sinusitis, dental abscess, upper RTI

Question 23

list the etiologies of microbial keratitis

Answer 23

Question 24

____ is a filarial nematode that can lead to blindness and characteristic ____ swellings

Answer 24

Loiasis (Loa loa) is a filarial nematode that can lead to blindness and characteristic Calabar swellings

Question 25

list the sites of inflammation and infection for otitis:

externa (OE)

media (OM) % chronic suppurative (CSOM)

interna

labrynthitis

Answer 25

Question 26

____ is important for differentiation of the different forms of otitis infections

Answer 26

Question 27

describe the pathogenesis of otitis externa

Answer 27

Question 28

list the primary causes of otitis externa

Answer 28

Question 29

list the 3 risk factors for acute otitis media

Answer 29

bottle feeding

daycare

exposure to tobacco smoke

Question 30

describe how an upper viral RTI can lead to otitis media

Answer 30

Question 31

acute otitis media is primarily due to ____ and ____

Answer 31

acute otitis media is primarily due to S. pneumoniae and non-typeable Haemophilus influenzae

Question 32

acute otitis media caused by Haemophilus influenzae is more likely to be (unilateral or bilateral?) and often with concurrent ____

Answer 32

acute otitis media caused by Haemophilus influenzae is more likely to be bilateral and often with concurrent conjunctivitis

Question 33

Labyrinthitis is caused by ____ infection

Answer 33

Labyrinthitis is caused by viral infection

Question 34

describe symptoms of labyrinthitis

Answer 34

Question 35

mastoiditis is often due to _____

Answer 35

mastoiditis is often due to untreated/unresolved otitis media

Question 36

“child presents with swelling of the earlobe, redness and tenderness behind the ear and bulging and drooping of the ear”

dx?

Answer 36

mastoiditis

Question 37

mastoiditis is often due to untreated/unresolved _____

Answer 37

mastoiditis is often due to untreated/unresolved otitis media