Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Neuro Block 3 - KJ > Conjunctivitis > Flashcards

Conjunctivitis Flashcards

1
Q

What are the order of layers in the back of the eyeball?

A

Sclera –> Choroid –> Retina –>

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What is in the center of the macula?

A

Fovea

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Where is the conjunctiva?

A

Covering the Sclera

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What sinuses are near the eye that infection could spread from?

A

Frontal Sinus, Ethmoid sinus, Maxillary Sinus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

How do pathogens get into deeper eye layers?

A

From blood borne carriage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What is blepharitis? What is it associated with?

A

Inflammatory disease of eyelid margin where too much oil is produced - chronic conjunctivitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What organism is most often associated with chronic conjunctivitis and blepharitis? What do you treat with?

A

Staphlyococcus epidermis [Hard to erradicate] - Often we may not want to treat this with antibiotics since they are so recurring - like onchocerciasis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a stye/hordeolum?

A

It’s localized inflammation often on lower lid due to bacterial growth in eyelash.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

How to treat a blepharitis/stye?

A

Keep the eyelid clean. Use warm compress or massage to open gland. Use Erythromycin ointment.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What is the mechanism of Erythromycin/Azithromycin?

A

Inhibits translation by binding 23S rRNA of the 50s subunit in bacteria.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What is the spectrum of Erythromycin/Azithromycin?

A

Broad coverage of rep. pathogen, Chlamydia

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What resistance developed against Erythromycin/Azithromycin?

A

Increased efflux, hydrolysis of drug by esterase’s, methylation of drug binding site

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are adverse effects of erythromycin/azithromycin?

A

GI discomfort, hepatic failure, and prolonged QT interval

–> inhibitors of cytochrome p450 enzymes (check with other medications)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What class and mechanism if Moxifloxacin?

A

Fluoroquinolone

Bactericidal, inhibits DNA replication (binary fissue) by binding bacterial DNA topo II (gyrase) and IV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the spectrum of moxifloxacin?

A

Broad spectrum, Gram + or - & atypical like Mycoplasma

Hospital acquired pneumonia & UTIs

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the resistance of moxifloxacin?

A

Overprescribed for UTI, respiratory and acute GI infections
Active efflux of drug
Mutations in topoisomerases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What are the adverse effects of moxifloxacin?

A

GI side effects, confusion, photosensitive

-Not good for pregnant & breastfeeding women due to arthropathy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are important facts to remember with moxifloxacin?

A

It creates chelate cations so don’t take with calcium, iron, aluminum and zinc - avoid dairy and juice with Ca
-Adjust for renal dysfunction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is the mechanism for Polymyxin B?

A

Binds to LPS (lipopolysaccharide) in the membrane creating holes ultimately leading to the release of cellular contents

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What is the spectrum for Polymyxin B?

A

Multi drug resistant Gram – bacilli including Pseudomonas aeruginose and Klebsiella pneumoniae
-Used in combo with other antibiotics to help facilitate entry

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are side effects of Polymyxin B?

A

Nephrotoxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

How does resistance develop against Polymyxin B?

A
  • It’s infrequent and slow to develop

- Cross resistance does not develop with any other presently used antibiotics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How do tears defend the eye?

A

They contain IgA and lysozyme & provide lubrication

24
Q

Describe IgA:

A

It’s a dimer. The secretory piece in the middle protects IgA from being degraded.

25
Q

What type of immune defense does the conjunctiva have?

A

Lymphocytes, plasma cells, neutrophils, and mast cells that produce antibodies and cytokines

26
Q

What is conjunctivitis?

A

Discharge, red eye, irritation, sensitivity to palpitation; caused by dilation and congestion of sub epithelial vessels

27
Q

What are noninfectious causes of conjunctivitis?

A

Allergic rhinoconjunctivitis (hay fever), chemical reaction, prolonged use of ocular medications, neoplasm, irritation from contact lens or foreign body

28
Q

Traits of Allergic conjunctivitis:

A
  • Mostly bilateral
  • Rarely has discharge
  • Usually has redness
  • No ear infection
  • Very itchy/pruritic
29
Q

Traits of Viral Conjunctivitis:

A
  • 35% bilateral
  • Discharge: mild, watery, sleepers
  • Usually redness
  • 10% have ear infection
  • No itchiness
30
Q

Traits of Bacterial Conjunctivitis:

A
  • -50-74% bilateral
  • Discharge is mucopurulent in younger children
  • Redness common in older children but NOT younger
  • 32-39% ear infection
  • Not itchy but may rub eyes
31
Q

What is the mechanism of hay fever/rhinoconjunctivitis (allergic)?

A

Hypersensitivity Type I

  1. Airborne allergen actives B cells
  2. B cells -> IgE
  3. IgE binds to surface of mast cell or basophil
  4. Another exposure to antigen
  5. antigen binds antibodies on mast cell
  6. Mast cell degranulates and releases histamine which causes inc. permeability and distention in blood capillaries (inflammation)
32
Q

How do you treat Hay fever?

A

Antihistamines, mast cell stabilizers, non steroidal anti-inflammatory drugs

33
Q

What should you avoid with hay fever?

A
  • Antigen & glucocorticoid

- Steroids effective but can cause complications like glaucoma, cataract & 2ndary infections

34
Q

What is the most common viral conjunctivitis in neonatal and post-natal?

A

Neonatal - HSV
Postnatal - Adenovirus (most common), Coxsackie A24, HSV 1 & 2, VZV (herpes zoster ophthalmic), EBV, rubella, mumps, influenza

35
Q

Describe typical clinical presentation of viral conjunctivitis:

A

Recent upper resp. tract infection, preauricular adenopathy

  • Benign and self limited in immune competent
  • May see acute hemorrhagic conjunctivitis: blood vessel pops but general resolves on its own
36
Q

How to treat viral conjunctivitis?

A

Cold compress and topical vasoconstrictors

37
Q

What are the traits of adenoviruses?

A
  • Non-enveloped
  • dsDNA
  • Lytic in epithelial cells and latent in lymphoid
  • Highly contagious spread through fomites like swimming pools
  • Has coxsackie receptor
  • Conjunctivia - strains 19 & 37
38
Q

What does the New AdenoPlus test do?

A
  • Dab and drag on conjunctiva

- Detects adenovirus hexon protein part of viral capsid

39
Q

What are the most common causes of acute bacterial conjunctivitis (mucopurulent) in children?

A

Staph. aureus, Streptococcus pneumoniae, Haemophilus influenzae
(not as often: Moraxella lacunata)

40
Q

What are the most common causes of acute bacterial conjunctivitis (mucopurulent) in
adults?

A 
Staphylococcus aureus
(sometimes strep. pneumonia, strep, progenies and pseudomonas aeruginosa)
41
Q

How to treat acute bacterial conjunctivitis (mucopurulent)?

A

Self-limited but may want to treat because it decreases morbidity and transmission
-Empiric treatment with gram + and - coverage
Trimethoprim and polymyxin ophthalmic drops
More expensive moxifloxacin drops

42
Q

What is the mechanism of trimethoprim?

A

Bacteriostatic

  • Inhibits bacterial dihydrofolate reductase (can’t make tetrahydrofolic acid for pyrimidines)
  • Has low affinity for mammalian response
43
Q

What is the mechanism for Polymyxin B?

A

Binds LPS in membrane creating holes ultimately leading got release of cellular contents
-Used for GRAM NEG., multi drug resistant

44
Q

What causes hyper acute bacterial conjunctivitis?

A

Neisseria gonorrhoeae (less often N. meningitidis)

45
Q

What does N. gonorrhoeae look like in the eye?

A
  • Copious yellow-green discharge
  • discharge covering eyes, red swollen
  • Swollen lymph nodes
46
Q

How to diagnose N. gonorrhoeae?

A
  • Gram stain for gram -, intracellular diplococci

- Growth on chocolate agar supplemented with vancomycin, collision, nystatin & trimethoprim (non sterile site)

47
Q

How to treat N. gonorrhoeae?

A

Promptly with SYSTEMIC ceftriaxone

-OR it can quickly cause corneal ulceration and perforation, can augment with topical antibiotics and irrigation

48
Q

What is Ophthalmia neonatorum?

A

Conjunctivitis or keratoconjunctivitis (cornea too) in first few weeks of birth.
-N. Gonorrhoeae, C. trachomatis, Staphylococcus, Streptococcus, E. coli, H. influenzae or H. simplex.

49
Q

How do you diagnose and treat Ophthalmia neonatorum?

A

Diagnose: cultures and smears
Treat: appropriate antimicrobial, often erythromycin
Prevent: prophylaxis with erythromycin ointment

50
Q

What are the two types of Chlamydia trachomatis?

A
  1. Inclusion conjunctivitis (serotypes D-K)
  2. Trachoma (serotypes A-C)
    - Coinfections should be considered - often N. gonorhoaea
51
Q

What is important about Trachoma?

A

It is the leading cause of blindness worldwide due to multiple infections since no long lasting immunity

52
Q

How do you diagnose Trachoma?

A

Direct fluorescent antibody

53
Q

How do you treat Chlamydia trachomatis?

A

Systemic azithromycin & improve hygiene

Treat partners with widespread prophylaxis - being used to try to eliminate Trachoma by 2020

54
Q

How does Chlamydia trachomatis spread?

A

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

55
Q

What form of Chlamydia trachomatis has a rigid outer membrane?

A

Elementary body (EB)

56
Q

How does HSV-1 present in eye?

A

Keratoconjunctivitis (conjunctiva and cornea)

Neuro Block 3 - KJ (16 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions