Eye Infection Microbiology

  1. Naked (non-enveloped), linear, double stranded DNA virus:
    • Adenovirus
    • Replicates in nucleus
  2. Most common cause of viral conjunctivitis:
  3. Fiber spikes is associated with which virus?
  4. Which virus causing eye problems is relatively resistant to drying, detergents, low pH and just stable in the environment in general?
    • Adenovirus
    • Capable of causing GI infections because of this
  5. Adenovirus fiber spikes contributes to:
    • Serotype
    • Tropism (wide range of infections)
    • Adhesin (attach to host tissues)
  6. T/F: Adenovirus gets its name because viral DNA has been found integrated in lymphoid tissue DNA
  7. How is adenovirus transmitted?
    • Close contact
    • Aerosols
    • Fecal-oral
    • Fingers
    • Fomites (shared towels, improperly sterilized instruments)
    • Inadequately chlorinated pools
  8. T/F: adenovirus conjunctivitis often occurs with pharyngitis and is not very contagious
    False; it is extremely contagious (bacterial causes of conjunctivitis is also very contagious)
  9. Viral conjunctivitis symptom:
    Watery or mucoserous discharge, burning, sandy or gritty feeling in eye
  10. Follicular conjunctivitis involves inflammation of mucosa of ___ conjunctiva; keratoconjunctivitis is inflammation of ___ and ____
    • Tarsal
    • Conjunctiva and cornea
  11. Adenovirus commonly have outbreaks in:
    Swimming pools, camps, military facilities, schools
  12. Histological hallmark of adenovirus conjunctivitis:
    Intranuclear inclusions
  13. HSV-1 and HSV-2 are what kind of virus?
    • Enveloped double stranded DNA virus
    • Herpesviridae family
  14. T/F: HSV and Adenovirus are both enveloped double stranded, linear DNA viruses
    False; adenovirus is non-enveloped (naked) double stranded, linear DNA virus
  15. Where does HSV replicate?
    Nucleus; like adenovirus
  16. T/F: HSV transmission can be through fomites (contact with the environment)
    No, because they are enveloped
  17. T/F: HSV causes conjunctivitis
    False; adenovirus causes conjunctivitis, HSV causes keratitis
  18. Which virus is the leading cause of infectious blindness in developed countries?
  19. HSV keratitis is usually ____ (laterality), with symptoms of ____,___,___ and may involve ____
    • Unilateral
    • Pain, blurring, watery discharge
    • Deeper stroma
  20. Exam demonstrates punctate/ diffuse dendritic lesions/ ulcers of corneal epithelium in Fluorescein stain, what is the pathogen?
  21. Ocular nematodes include:
    • Loa loa
    • Onchocerca volvulus
    • Toxocara canis
  22. Vector and host for Loa loa:
    • Vector= Deer fly, mango fly
    • Definitive host = human
  23. T/F: microfilariae form of loa loa is responsible for pathology
    False; adults are responsive
  24. Mango fly, deer fly bites us and transmits ____ form of ______ into us. These mature into ____ in our ____ tissue, which can then migrate to any area of our body, including _____
    • Mature
    • Larvae
    • Adults
    • Subcutaneous
    • Conjunctiva
  25. What is calabar swelling?
    Localized, transient subcutaneous swelling caused by loa loa
  26. See a worm crawling beneath the conjunctiva, think:
    Loiasis, causing conjunctival inflammation and edema
  27. T/F: loiasis does not require treatment because symptoms resolve once the worm leaves the eye
  28. Which nematode causes keratitis?
    Onchocera volvulus
  29. Which nematode infection is also known as river blindness?
  30. Vector and host of Onchocerca volvulus:
    • Vector- black fly
    • Host- human
  31. Onochocerca has ____ as its vector, while loa loa has _____ as its vector. Both have ___ as definitive host
    • Black fly
    • Mango/ Deer fly
    • Human
  32. Which nematodes microfilariae circulates in the blood stream and which ones wander into tissues?
    • Bloodstream – loa loa
    • Tissue- onchocerca
  33. T/F: Onchocerciasis can lead to blindness because inflammation caused by adult nematodes that die in the eye result in reversible lesions on cornea and without treatment can lead to clouding of cornea and subsequently blindness.
    False; it’s the wandering microfilariae that die in our eye that leads to possible blindness, not adults
  34. Which eye worm is commonly seen in hot, humid climates and has dog as its definitive host?
    Toxocara canis
  35. Which worm can cause visceral larva migrans and ocular larva migrans?
    Toxocara canis
  36. T/F: humans are accidental hosts for toxocara canis
    True; its definitive host is dogs
  37. What for of toxocara canis can be found circulating in our bodies?
    • Larvae circulate in us, no adults because those are in doggies
    • Also no eggs are shed in us
  38. A 3 year old child likes to play and eat dog poop, what form of toxocara canis might enter this child’s body?
    Larvae will hatch in his small intestine, penetrate the intestinal wall and migrate via blood stream
  39. Once Toxocara canis larvae is in the blood stream, what are the two places that it loves to go to?
    Liver and eye
  40. Hepatic granuloma is often seen in which disease caused by toxocara canis?
    Visceral larva migran
  41. Ocular larva migran is ____ (laterality), and associated with _____ inflammation in the _____
    • Unilateral
    • Granulomatous
    • Retina
  42. T/F: Ocular larva migran, caused by toxocara canis, can lead to reversible vision loss
    False; it’s irreversible
  43. Biggest risk factor for development Acanthamoeba keratitis is:
    Contact lens
  44. Acanthamoeba is an amoeba with _____ which are pseudopods that helps it move
  45. T/F: acanthamoeba keratitis can only occur in immunocompromised contact lens wearer
    False; it can occur in healthy contact lens wearer; in immunocompromised individuals, acanthamoeba can lead to granulomatous amebic encephalitis
  46. Cysts of acanthamoeba have _______ characteristic.
    • Double-walled
    • With the outer wall kinda wrinkled and the inner wall having polygonal shape
  47. T/F: transmission of acanthamoeba into our body is only though its trophozoite form
    False; both cyst and trophs can enter the human body
  48. Corneal scraping of acanthamoeba keratitis will show _____
    Start shape cysts
  49. T/F cysts and trophs of acanthamoeba likes to adhere to bacterial biofilms
  50. Conjunctiva that covers the globe is _____ conjunctiva. Conjunctiva covers the lining of lids is ___ conjunctiva
    • Bulbar
    • Tarsal
  51. Stye is also know as _____, which is a ______, meaning inflammation of eyelash follicles. Most commonly due to ______ which infects the _____ glands
    • Hodeolum
    • Blepharitis
    • Staph aureus
    • Sebaceous
  52. Most common risk factor for orbital cellulitis is _____
  53. Most common bacterial agents of conjunctivitis:
    S aureus, Strep pneumo, nontypeable H flu, Moraxella
  54. T/F: bacterial and viral conjunctivitis are both self-limiting
    True; bacterial can be treated with abx for shorter clinical course and reduce person-person spread
  55. Hyperacute bacterial conjunctivitis is associated with which pathogen?
    Neisseria, mostly N gonorrhoeae
  56. Neonatal conjunctivitis is caused by:
    • N gonorrhoeae (ophthalmia neonatorum)
    • Chlamydia trachomatis (most prevalent form)
  57. T/F: Chlamydia trachomatis is not an STI, can cause chronic keratoconjunctivitis
  58. Contact lens wearers should be terrified by which two pathogens that can cause keratitis:
    • Pseudomonas
    • Acanthamoeba
  59. Bacterial keratitis pathogens are___,___, Viral cause of Keratitis is _____ and protozoal cause is _______, and nematode ______.
    • S aureus- most common
    • Pseudomonas – contact lens wearer
    • HSV-1
    • Acanthamoeba
    • Onchocerca volvulus
  60. What is hypopyon?
    Collection of inflammatory cells in the anterior chamber of the eye
  61. What is endophthalmitis?
    • Inflammation of intraocular fluids and tissue
    • This is a medical emergency- vision threatening
  62. Etiologic agents of endophthalmitis
    • Bacterial- CoNS, S aureus, streptococci
    • Penetrating trauma- Bacillus
    • Fungi- candida, aspergillus
Card Set
Eye Infection Microbiology
Heme Onc Final