Eye Infections! - A.Prun

Question 1

Most common infectious conjunctivitis?

Answer 1

Adenovirus

Question 2

How do you manage allergic conjuctivitis?

Answer 2

ANtihistamines, avoid antigen

Steroids effective, but have complications

Question 3

What do you see in hyperactute nesseria gonorrhea conjuctivitis?

How do you treat it?

Answer 3

Copious yellow-green discharge (purulent)

Treat promptly with systemic ceftriaxone otherwise can quickly progress to corneal ulceration and perforation, can augment with topical antibiotics and irrigation

Question 4

Outline the life cycle of chlamydia trachomatis:

Answer 4

Elementary body (EB) enters epithelial cells, converts to reticulate body (RB), and then replicates using binary fission

They are elementary bodies external to the cell, and this structure is rigid and protected to survive

Question 5

What kinds of virulence factors does pseudomonas use and how do these cause problems in the eye?

Answer 5

Bacterial cell surface adherence factors and secreted cytotoxins like elastase and alkaline protease destroy corneal epithelium.

The host immune response damages the cornea leading to scarring and loss of visual acuity.

Question 6

What is blepharitis?

Answer 6

Eye lid infection

Question 7

What do you call infection of the cornea?

Answer 7

Kerititis

Question 8

What would you call infection of the retinal or choroid layers?

Answer 8

Chorioretnitis

Question 9

Keratoconjuctivitis refers to:

Answer 9

Infection of the conjunctiva and cornea

Question 10

What is endophtalmitis?

Answer 10

Infection of aqueous and vitreous humor

Question 11

Common cause of viral conjuctivitis in neonates?

Answer 11

HSV-2 (From mom)

Question 12

Most common viral conjunctivitis?

Answer 12

adenovirus

Question 13

How do you treat viral conjunctivitis?

Answer 13

Cold compress and topical vasoconstrictor

Question 14

What are some characteristics of adenovirus?

Answer 14

non-enveloped, double-stranded DNA virus
Lytic in epithelial cells and latent in lymphoid
Highly contagious spread through fomites like swimming pools

Question 15

Most common pathogens in child and adult bacterial conjuctivitis:

Answer 15

Children - Staph Aureus, Strept Pneumoniae, HEmophilus Influenzae

Adults - Staph Aureus

Question 16

Best empiric treatment for the gram + and - ?

Drug mechanisms?

Answer 16

Moxifloxacin - Fluoroquinolone inhibiting DNA topoisomerase

OR

Trimethoprim - Folate Synthesis inhibitor
and
Polymixin B - Creates hole in bacterial membrane

Question 17

What are the pathogens of hyperactue bacterial conjuctivitis?

Answer 17

Neisseria Gonorrhea
Neisseria Meningitiis (sometimes)

Question 18

What is the the treatment for opthalmia neonatroum?

Answer 18

Prophylaxis with erythromycin ointment.

Remember this is neonatal conjuctivitis recieved from mom during birth.
Could be N. gonorrhoeae, C. trachomatis, Staphylococcus, Streptococcus, E. coli, H. influenzae or H. simplex.

Question 19

REVIEW

Macrolide drug mechanism and adverse effects

Answer 19

Macrolides like erythromycin, azithromicin…

50S ribosomal inhibitor

Gi problems, hepatic failure, prolonged QT

Question 20

Leading cause of blindness worldwide?

Any way to treat?

Answer 20

Chlamydia Trachomatis

Treat with azithromycin and improve hygiene

Question 21

What blephartis-related chronic problems can Staph Aureus cause?

Answer 21

Styes - external localized inflammation often on lower lid due to bacterial growth in eyelash follicle
and
Chalazions - small lump plugging the meibomian gland

Question 22

How should you treat HSV-1 keratoconjuctivitis?

Drug mechanisms?

Answer 22

if the cornea is involved, treat with:
topical Trifluridine - also stops DNA synthesis, but is more toxic because it can be activated by host
and
systemic Acyclovir - Acts as bad DNA substrate to inhibit DNA synthesis

Question 23

What free-living organism can frequently reside in poorly-stored contact lens fluids to create eye infections?

Answer 23

Acanthemoeba

Question 24

What are symptoms of chorioretinitis?

Causes of chorioretinitis?

Answer 24

Blurred vision and visual field defects

Congenital toxoplasma and CMV are most common (especially in HIV individuals and neonates)

Toxocara Canis and Onchocerca Volvulus

• parasite worms that cause these infections
• OV = river blindess transmitted by sand flies

Question 25

Endophtalmitis is rare. When does it usually occur?

Answer 25

After a recent introcular surgery, like cataracts

Agent comes from normal flora, like pseudomonas, staph, or candida