Deck 41: Ocular Infections

Question 1

What organism causes neonatal conjunctivitis, lymphogranuloma venereum (LGV), and trachoma?

A) Chlamydia trachomatis
B) Streptococcus trachomatis
C) Staphylococcus aureus
D) Neisseria meningitidis

Answer 1

A

Question 2

Bacteria that cause keratitis associated with contact lenses often initiate infection through which of the following?

A) Biofilm formation
B) Growth in the contact lens
C) Attachment to the lens
D) Contamination of the fluid coating the lens

Answer 2

A

Question 3

What are the most frequent etiologic agents of endophthalmitis?

A) Staphylococcus epidermidis
B) Staphylococcus saprophyticus
C) Staphylococcus aureus
D) Escherichia coli

Answer 3

A

Question 4

Microorganisms can gain entry into orbital tissue in all the following ways, except

A) surgery.
B) eyelid infections.
C) dental caries.
D) carrying organisms on facial skin.

Question 5

What is the most common infection of the lacrimal gland?

A) Blepharitis
B) Dacryocystitis
C) Canaliculitis
D) Conjunctivitis

Question 6

All of the following are common risk factors associated with ocular infection, except

A) age.
B) sex.
C) personal hygiene.
D) social economic status.

Question 7

What is blepharitis?

A) Inflammation of the conjunctiva
B) Inflammation of the sclera
C) Inflammation of the lacrimal gland
D) Inflammation of the lid margins

Question 8

A layer of tears blankets the cornea to provide all of the following, except

A) waste elimination.
B) optical clarity.
C) lubrication.
D) nutrition.

Question 9

Which of the following make up the majority of indigenous ocular microbial biota?

A) Mobiluncus and Lactobacillus
B) Coagulase-negative Staphylococcus and Corynebacteria
C) Coagulase-negative Staphylococcus and Lactobacillus
D) Moraxella and Corynebacteria

Question 10

All of the following factors determine whether a pathogen can cause disease in the eye, except

A) characteristics of the invading organism.
B) health of normal microbiota.
C) integrity of underlying tissue.
D) host's immune system.

Question 11

Which condition is a medical emergency in children?

A) Chronic sinusitis
B) Lacrimitis
C) Preseptal cellulitis
D) Orbital cellulitis

Question 12

A patient who makes her own saline solution for her contact lenses is examined at her physician's office because she has a blood-red, infected right eye. The physician orders bacterial, fungal, and viral cultures, all of which are negative. What is the most probable cause of this infection?

A) Acanthamoeba spp.
B) Entamoeba spp.
C) Trypanosoma spp.
D) Leishmania spp.

Question 13

How should vitreous washings be processed in the laboratory for recovery of bacterial pathogens?

A) Directly plate the fluid.
B) Centrifuge the fluid.
C) Pass the fluid through 0.45 µL membrane filter and lay filter on media.
D) Dilute the fluid with normal saline.

Question 14

What is the leading cause of infectious blindness and ocular morbidity in the United States?

A) Epstein-Barr virus
B) Cytomegalovirus (CMV)
C) Human papillomavirus (HPV)
D) Herpes simplex virus (HSV)

Question 15

When performing conjunctival cultures, all of the following are required for best results, except?

A) The specimen should be collected on a transport swab.
B) The sample should be plated directly when possible.
C) The specimen requisition must be filled out completely.
D) The ophthalmologist must communicate with the personnel performing the culture.

Question 16

What parasite is responsible for causing a form of blindness in West Africa?

A) Hookworm
B) Pinworm
C) Loa loa
D) Whipworm

Question 17

Contact with bees and other insects is a high risk factor for keratitis caused by

A) Fusarium sp.
B) Microsporidia.
C) Adenovirus.
D) Mycobacterium abscessus.

Question 18

What contains enzymes and other factors that protect the conjunctiva from microbial invasion?

A) Skin
B) Tears
C) Eye lid
D) Eye lashes

Question 19

All of the following viruses cause acute viral conjunctivitis, except

A) adenovirus.
B) caliciviruses.
C) herpesviruses.
D) enteroviruses.

Question 20

What condition is considered a true ocular emergency?

A) Conjunctivitis
B) Blepharitis
C) Microbial keratitis
D) Yellowing of the sclera

Question 21

Bacterial keratitis associated with contact lenses in warmer climates is commonly caused by which of the following organisms?

A) Corynebacterium spp.
B) Staphylococcus aureus
C) Pseudomonas aeruginosa
D) Viridans streptococci

Question 22

Nosocomial transfer of which virus can occur during optometry examinations through contaminated tonometer tips?

A) Adenovirus
B) Caliciviruses
C) Herpesviruses
D) Enteroviruses

Question 23

What is the most common route of administration for ophthalmic drugs?

A) Topical
B) Intravenous
C) Intramuscularly
D) Oral