Conjunctiva

Question 1

conjunctiva (rankin)

Red Eye

Answer 1

• Conjunctival hyperemia
  
  • Extensive branching
  • Extraocular disease
• Episcleral Injection
  
  • Radial pattern from limbus
  • Dark red
  • Intraocular disease
• Subconjunctival hemorrhage
  
  • Difuse red
  • Trauma/bleeding disorder

Question 2

Ocular Discharge

Answer 2

• Serous
  
  • Viral (FHV 1)
  • Epiphora
• Mucoid
  
  • KCS (dry eye disease)
• Mucopurulent
  
  • Bacterial infection

Question 3

conjunctiva (rankin)

Diagnostic Tests for “Red Eye”

Answer 3

• Fluorescein stain
• Schirmer tear test
  
  • don’t do for deep ulcer
• Intraocular pressure
  
  • don’t do for deep ulcer
• +/- Conjunctival cytology
• +/- Aerobic culture and sensitivity

Question 4

Ophthalmia Neonatorum

Answer 4

• Infection prior to lid separation
  
  • Puppies bacterial
  • Kittens viral (FHV-1) or Chlamydia
• Treatment
  
  • Separate eyelids
  • Flush with sterile saline
  • Puppies-broad spectrum antibiotic ointment-BNP (bacitracin/neomycin/polymyxin B)
  • Kittens tetracycline ointment ( Terramycin ®)
  • Treat 4-6 times daily
• Sequelae
  
  • Symblepharon (conjunctiva stuck to more conjunctiva, or conjunctiva to cornea), corneal perforation, corneal scar formation, blindness…

Question 5

conjunctiva (rankin)

Canine Conjunctivitis

Answer 5

• Rarely infectious!!!!!!
• Usually secondary to other abnormalities
  
  • Entropion, ectropion, trichiasis, eyelid tumors…
  • Tear film abnormalities-keratoconjunctivitis sicca (KCS)
  • Irritants-chemicals, dust, smoke….
• Bacteria can frequently be cultured at low numbers from NORMAL conjunctiva
  
  • Staphylococcus , Streptococcus , Cornyebacterium , and Bacillus spp.

Question 6

conjunctiva (rankin)

Treatment of Canine Conjunctivitis

Answer 6

• Treat the underlying cause
• Broad spectrum topical antibiotic QID
• Topical corticosteroids (hydrocortisone)
  
  • Fluorescein negative!!!
• If no response to therapy
  
  • Re-evaluate diagnosis

Question 7

conjunctiva (rankin)

Follicular Conjunctivitis

Answer 7

• Typically seen in young dogs
• Lymphoid follicles bulbar surface of the nictitans
• Etiology-immune mediated, allergic, chronic irritation….
• Treatment-topical steroids +/- topical antihistamines (olopatadine)

Question 8

conjunctiva (rankin)

Feline Conjunctivitis

Answer 8

• Usually infectious!!!
  
  • Do NOT use topical steroids!
  • Feline herpesvirus 1 FHV-1
  • Chlamydia
  • Mycoplasma
  • Calicivirus
• Eosinophilic conjunctivitis

Question 9

conjunctiva (rankin)

Feline Herpesvirus 1 FHV-1

Answer 9

• Most common cause of feline conjunctivitis
  
  • Seroprevalance up to 97% of cats
  • >80% of cats that recover are carriers
  • Approximately ½ of the carriers shed under normal conditions
• Corneal ulcers/keratitis
• Latency occurs in trigeminal ganglion
• URI
• Kittens most susceptible
• Short lived in the environment <18hrs
• Virus is inactivated by most disinfectants
• Sneezing carriers the virus approximately 4 feet

DON’T USE TOPICAL STEROIDS IN CATS

Question 10

conjunctiva (rankin)

FHV-1 Diagnostics

Answer 10

• Clinical signs!!!!
• Conjunctival cytology
  
  • Intranuclear inclusions, PMNs
• PCR - sensitive and specific
• IFA - insensitive
  
  • Fluor. stain may cause false +
• Serology (serum neutralization titer) insensitive
• Virus isolation
  
  • Definitive dx for acute infection
  • Insensitive for chronic infection

Question 11

conjunctiva (rankin)

FHV-1

• time to recover
• when to treat

Answer 11

• Most recover in 10-21 days
• Which cases should you treat?
  
  • Moderate to severe conjunctivitis
  • Corneal disease

Question 12

conjunctiva (rankin)

Treatment of FHV-1

Answer 12

• Topical and systemic antiviral medications
• Oral lysine
• Decrease stress

Question 13

conjunctiva (rankin)

Antiviral Topical Treatment

Answer 13

• Cidofovir 0.5% solution
  
  • Compounding pharmacy
  • 2 times daily
• Idoxuridine 0.1% solution
  
  • Compounding pharmacy
  • 4-8 times daily
• Trifluridine 1% solution
  
  • Refrigerated
  • Topically irritating
  • 4-8 times daily

Question 14

conjunctiva (rankin)

Antiviral Systemic Treatment

Answer 14

• Famciclovir
  
  • 250 mg tablets ( Famvir ®)
  • 30-40 mg/kg B-TID po
  • NOT the same as valacyclovir!
• Lysine
  
  • 250 mg po BID kittens
  • 500 mg po BID cats
  • Give with food

Question 15

conjunctiva (rankin)

Antiviral Therapy for FHV-1

Answer 15

Continue therapy for at least 1 week after resolution of clinical signs

Question 16

Sequela to FHV-1

Answer 16

• Recurrence
• Corneal disease/ulceration /perforation
• Chronic epiphora
• Symblepharon

Question 17

conjunctiva (rankin)

Chalmydia felis

Answer 17

• URI in young cats
• Chemosis usually begins unilaterally then bilateral
• Follicles with chronicity

Question 18

conjunctiva (rankin)

Chlamydia Diagnostics

Answer 18

• Cytology
  
  • Intracytoplasmic inclusion bodies
  • Days 3-14
• PCR

Question 19

conjunctiva (rankin)

Chlamydia Treatment

Answer 19

• Oral medication
  
  • **Doxycycline (kittens over 4 weeks of age)
    
    • 5mg/kg po BID OR 10mg/kg SID
    • Esophageal stricture
  • Azithromycin (5-10mg/kg SID)
  • Pradofloxacin (5-7.5 mg/kg SID)
• Treat for at least a month
  
  • Ideally at least 2 weeks beyond resolution of clinical signs
• Topical medications QID
  
  • In addition to oral therapy
  • Tetracycline ( Terramycin ®)
  • Erythromycin
• Recurrence common
• Zoonotic - rarely

Question 20

conjunctiva (rankin)

Mycoplasma

Answer 20

• Mycoplasma felis and M. gatae
• Opportunistic
• Conjunctival pseudomembranes
• Diagnosis
  
  • Cytology-small cytoplasmic basophilic inclusion bodies
  • Culture in special media
  • PCR test for M. felis
• Pathogenicity
  
  • Questionable
  • Isolated from normal cats

Question 21

conjunctiva (rankin)

Mycoplasma Treatment

Answer 21

• Topical medications QID
  
  • Tetracycline ( Terramycin ®)
  • Fluoroquinolones
• Oral medication
  
  • Doxycycline (kittens over 4 weeks of age)
    
    • 5mg/kg po BID OR 10mg/kg SID
    • Esophageal stricture
  • Pradofloxacin (5-7.5 mg/kg SID)
• Duration of therapy
  
  • At least 2 weeks

Question 22

conjunctiva (rankin)

Calicivirus

Answer 22

• URI
• Oral and nasal ulceration
• Polyarthritis
• Low pathogenicity for conjunctiva
• Topical antivirals are ineffective
• RNA virus
• Supportive care

Question 23

Conjunctival Neoplasia

Answer 23

• Mast cell tumor
• Papillomas
• Hemangioma
• Lymphoma
• Melanoma
• SCC

Question 24

Answer 24

Mast cell tumor

Question 25

Answer 25

Papillomas

Question 26

Answer 26

* Hemangioma * Hemangiosarcoma

Question 27

Answer 27

Lymphosarcoma

Question 28

Answer 28

Melanoma

Question 29

Answer 29

SCC

Question 30

Geographic Infectious Conjunctival Lesions

Answer 30