7: Ocular and Respiratory Infections

thin membrane covering the white of the eye

conjunctiva

white of the eye

sclera

membrane that covers the pupil & iris

cornea

anterior internal liquid of eye

aqueous humor

posterior internal liquid of eye

vitreous humor

normal flora of the eye

• S. epidermis

• S. aureus

• Lactobacillus

• Cutibacterium

• H. influenzae

Which organism is most frequently encountered normal flora of the eye?

S. epidermis

ocular infection routes

• broken barriers

• bloodstream

• sinus infections

inflammation of edges of eyelids or glands near eyelids

blepharitis

• red, swollen, tender eyelids

• itching and greasy or crusty deposits around eyelashes

• can lead to a sty

blepharitis

Which infection can lead to a chronic cyst?

blepharitis

blepharitis causes

• S. aureus

• Phthirus pubis

• HSV

Which infection is known as pink eye?

conjunctivitis

• results from allergies or infections

• highly contagious

• age-specific

conjunctivitis

conjunctivitis causes

• G+: S. pneumo, S. pyogenes, S. aureus

• G-: Haemophilus, C. trachomatis, N. gonorrhoeae, Moraxella

• viruses: adenoviruses, HSV, VZV

• inflammation of cornea, causing ulcerations

• may lead to vision loss due to rapid destruction of cornea

keratitis

Which ocular infection involves:

• corneal ulceration

• stromal abscess formation

• surrounding corneal edema

• anterior segment inflammation

keratitis

Which ocular infection has these Sx:

• reduced vision

• pain, often sudden

• increased sensitivity to light

• excessive tearing or discharge

keratitis

non-infectious keratitis causes

• minor injury

• improper use of contacts

infectious keratitis causes

• bacteria: S. aureus, S. pneumo, P. aeruginosa, Moraxella, Bacillus

• viruses: HSV, adenoviruses, VZV

• fungi: Fusarium, Aspergillus, Candida, Acremonium, Curvularia

• protozoa: Acanthamoeba

inflammation of retina & underlying choroid or uvea

chorioretinitis & uveitis

choroid + ciliary body + iris

uvea

primary vascular layer of the eye

uvea

Which ocular infection involves:

• blurred vision

• pink eye

• sensitivity to light

• continuous tearing

chorioretinitis & uveitis

chorioretinitis & uveitis primary causes

• Candida

• Toxoplasma gondii

• Toxocara

Which organism is from cat litter?

Toxoplasma gondii

Which organism is a roundworm, whose larvae migrate to the eye?

Toxocara

infection of aqueous or vitreous humor

endophthalmitis

Which ocular infection:

• tends to occur after surgery or trauma

• rapid progression, often leading to blindness

endophthalmitis

rare chronic inflammation of lacrimal canals

lacrimal infection/canaliculitis

lacrimal infections/canaliculitis causes

• Actinomyces

• Cutibacterium

inflammation of lacrimal sac

dacryocystitis

dacryocystitis causes

• bacteria: S. pneumo, S. aureus, S. pyogenes, H. influenzae

• fungi: C. albicans, Aspergillus

acute inflammation of lacrimal gland

dacryoadenitis

dacryoadenitis causes

• viruses: mumps, EBV, VZV

• bacteria: S. pneumo, S. aureus, S. pyogenes, T. pallidum, C. trachomatis

What type of swab is toxic for viruses?

calcium alginate

What is the direct visual exam for bacteria?

PMN count

What is the direct visual exam for viruses?

lymphocytes/monocyte count

What is the direct visual exam for HSV?

Tzanck smear for multinucleated epi cells

What is the direct visual exam for HSV & VZV?

direct fluorescence assay

What is the direct visual exam for Chlamydia?

monoclonal Ab conjugated fluorescein

What is the direct visual exam for Acanthamoeba?

wet prep & trichrome stain

Which ocular specimen is used for stab inoculation of BAP?

corneal scrapings

What are the incubation conditions for corneal scraping cultures?

5-10% CO2

Ear normal flora

• Pneumococcus

• Cutibacterium

• S. aureus

• enterics

• P. aeruginosa

• Candida

external ear infections

otitis externa

acute otitis externa causes

• S. aureus

• S. pyogenes

• P. aeruginosa

• GNRs

ear infection resulting from drainage from middle ear in Pts w/ chronic suppurative otitis media or perforated eardrum

chronic otitis externa

chronic otitis externa causes

• P. aeruginosa

• anaerobes

middle ear infection resulting from abnormalities of auditory tubes

otitis media

What is a complication of otitis media

mastoiditis

infection of bone in ear

mastoiditis

acute otitis media causes

• S. pneumo

• H. flu

• Moraxella

• S. pyogenes

• resp syncytial virus

• flu virus

chronic otitis media causes

anaerobes

ear specimens

• tympanocentesis

• swab or bone biopsy of mastoid

aspirate from middle ear fluid

tympanocentesis

What are the direct visual exams for ear infections?

• calcofluor white/PAS stain

• methenamine silver

For which ear specimens/infections do you inoculate aerobic media?

• tympanocentesis

• chronic otitis media

• mastoiditis

nose natural defenses

• nasal hair

• mucociliary cells

• sneezing

mouth/throat natural defenses

• coughing

• normal flora

How does the immune system defend the respiratory tract?

• phagocytosis

• immunoglobulins

What tests are run for pertussis?

• culture on Bordet-Gengou

• DFA stain

Where are the vocal chords located?

the larynx

• hoarseness due to swollen vocal chords

• weak/loss of voice

• tickling sensation & rawness

laryngitis

Which upper resp infection is caused by overuse or irritation from yelling, smoking, viral or bacterial infection?

laryngitis

Which upper resp infection causes swelling & possible blockage of trachea?

epiglottitis

Which upper resp infection most frequently affects 2-6 y.o?

epiglottitis

Which upper resp infection is Tx with Hib vaccine?

epiglottitis

Which upper resp infection involves:

• fever

• sore throat

• difficulty swallowing & breathing

epiglottitis

epiglottitis bacterial agents

• H. flu type b

• Pneumococcus

• Strep A-C

inflammation of salivary glands under cheeks

parotitis

Which upper resp infection involves:

• swelling of tissues

• dry mouth

• strange taste

• mouth or facial pain

parotitis

Which upper resp infection is Sjogren’s syndrome?

parotitis

Which upper resp infection can have an autoimmune cause?

parotitis

Which type of parotitis is caused by bacteria?

purulent parotitis

purulent parotitis causes

• S. aureus

• Strep

• Haemophilus

What are the types of parotitis?

• autoimmune

• purulent

• viral

• common cold

• viral infection of upper resp tract

rhinitis

What is the most common virus that causes rhinitis?

rhinoviruses

Which upper resp tract infection has these complications:

• tonsil abscesses

• upper airway obstruction

• rheumatic fever

• acute glomerulonephritis

pharyngitis/tonsillitis

What is the main cause of pharyngitis/tonsillitis?

S. pyogenes

Which upper resp infection involves a pseudomembranous membrane?

pharyngitis caused by C. diphtheriae

What specimen is used for B. pertussis?

nasopharyngeal swab of ciliated epi cells

What media is used for B. pertussis?

Bordet-Gengou

acute necrotizing ulcerative gingivitis; “trench mouth”

vincent’s angina

What organism causes vincent’s angina?

Fusobacterium

What upper resp infection can spread to the carotid artery?

peritonsillar abscesses

Which organism causes peritonsillar abscesses?

Fusobacterium

• purulent nasal & postnasal discharge

• pressure over sinus areas of face

acute sinusitis

Which upper resp infection is associated with bacterial infection following resp infection?

acute sinusitis

Which upper resp infection involves:

• inadequate drainage

• impaired mucociliary clearance

• mucosal damage

chronic sinusitis

air-filled cavities in the head

sinuses

inflammation of mucous membranes of oral cavity

stomatitis

Which oral infection involves canker sores & cold sores

stomatitis

aphthous ulcers; non-contagious

canker sore

fever blisters resulting from HSV

cold sore

white patches of exudate in mouth

thrush

thrush cause

Candida

root canal causes

• anaerobes

• Strep

orofacial odontogenic infection causes

• anaerobes

• Strep