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Gregory J. Nixon OD, FAAO

Associate Dean for Clinical Services

Professor of Clinical Optometry

nixon.24@osu.edu

The content of this COPE approved lecture was

prepared independently without input or sponsorship

from any industry source

The speaker has no direct financial or proprietary

interest in any products or services contained within

the presentation

Present consultant/affiliations:

Anadem Publishing

Surface Lid disease

Anterior blepharitis

MGD

Bacterial Conjunctivitis

Microbial keratitis (MK)

Prophylaxis

pre/post surgery

when epithelial barrier is lost

Which antibiotics do we use and when?

Do we need an antibiotic at all?

Balance therapeutic effect vs. side effect

What is the likely offending bacterial agent?

Which medication is our drug of choice for the

presentation?

Proper Dosing

Complete full course of antibiotics (7-10days)

Drug penetration/absorption

Selective Toxicity

Spectrum of Activity

Mechanism of Action

Microbial Resistance

Duration of Action/Dosing

Bacitracin

Polymyxin B

Aminoglycosides

Tobramycin

Gentamycin

Neomycin

Macrolides

Erythromycin

Azithromycin

Sulfonamides

Fluoroquinolones

Ciprofloxacin

Levofloxacin

Ofloxacin

Gatifloxacin

Moxifloxacin

Besifloxacin

Combinations

Polymyxin B & Trimethoprim

AK-Poly-Bac

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Most pervasive in ocular flora is Staphylococcus aureus: Gram (+)

Staphylococcus epidermidis: Gram (+)

Streptococcus pneumoniae: Gram (+)

Others of concern: Haemophilus influenzae: Gram (-)

Pseudomonas aeruginosa: Gram (-)

Chlamydia trachomatis: Gram (-)

Neisseria gonorrhoeae: Gram (-)

Treponema pallidum: Gram (-)

Ocular TRUST (Treating Resistance in

the US Today) Study, Ocular TRUST 2,

Ocular TRUST 3 50% of Staph isolates were methicillin resistant

62% of coagulase negative staphylococci were

methicillin resistant

Asbell PA, Colby KA, Deng S, et al. Ocular TRUST: nationwide antimicrobial susceptibility patterns in ocular

isolates. Am J Ophthalmol. 2008;145(6):951-958.

Review of Optometry, Supplement May 2012. Clinical Guide to Ophthalmic Drugs

ARMOR (Antibiotic Resistance in Ocular

Microorganisms) Study Initiated in 2009 and repeated annually

2017 results released at ARVO 2018

42.2% of Staph isolates were methicillin resistant

49.7% of coagulase negative staphylococci were

methicillin resistant

Asbell PA, Sanfilippo CM, et al. Antibiotic Resistance Among Ocular Pathogens in the United States Five-Year

Results From the Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) Surveillance Study.

JAMA Ophthalmol. 2015;133(12):1445-1454.

Asbell PA, Sanfilippo CM, et al. Antibiotic Resistance Among Ocular Pathogens in the United States Five-Year

Results From the Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) Surveillance Study.

JAMA Ophthalmol. 2015;133(12):1445-1454.

Bacterial Resistance

MSSA AND MRSA RESISTANCE RATES

Azithromycin 41.9 - 93.3%

Ciprofloxacin 13.3 - 76.1%

Gatifloxacin 11.0 - 68.4%

Moxifloxacin 7.7 - 56.8%

Besifloxacin NA

Tobramycin 4.0 - 40.6%

Trimethoprim 2.9 - 7.2%

Asbell PA, Sanfilippo CM, et al. Antibiotic Resistance Among Ocular Pathogens in the United States Five-Year

Results From the Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) Surveillance Study.

JAMA Ophthalmol. 2015;133(12):1445-1454.

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COAGULASE NEGATIVE RESISTANCE RATES

Azithromycin 44.5 - 78.3%

Ciprofloxacin 14.4 – 54.6%

Gatifloxacin 10.4 – 45.1%

Moxifloxacin 9.4 – 40.4%

Besifloxacin NA

Tobramycin 2.0 – 14.4%

Trimethoprim 12.5 – 39.6%

Asbell PA, Sanfilippo CM, et al. Antibiotic Resistance Among Ocular Pathogens in the United States Five-Year

Results From the Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) Surveillance Study.

JAMA Ophthalmol. 2015;133(12):1445-1454.

Asbell PA, Sanfilippo CM, et al. Antibiotic Resistance Among Ocular Pathogens in the United States Five-Year

Results From the Antibiotic Resistance Monitoring in Ocular Microorganisms (ARMOR) Surveillance Study.

JAMA Ophthalmol. 2015;133(12):1445-1454.

Review of Optometry, Supplement May 2016. Clinical Guide to Ophthalmic Drugs

Bacitracin

Polymyxin B

Aminoglycosides

Tobramycin

Gentamycin

Neomycin

Macrolides

Erythromycin

Azithromycin

Sulfonamides

Fluoroquinolones

Ciprofloxacin

Levofloxacin

Ofloxacin

Gatifloxacin

Moxifloxacin

Besifloxacin

Combinations Polymyxin B & Trimethoprim

AK-Poly-Bac

Combination of Polymyxin B and Trimethoprim

(Polytrim® and also as generic)

Spectrum of activity:

Gram (+) including Staph, Strep, &MRSA

Gram (-) including H. Flu &

Pseudomonas

Dosage: 1 gt q 3h x 7d

Aminoglycosides

0.3% tobramycin (Tobrex® ) sol & ung

• Also available generically

• QID x 7d

0.3% gentamycin(Garamycin®) sol & ung

• Also available generically

• QID x 7d

4TH GENERATION FQ CURRENTLY ONLY

APPROVED FOR TREATMENT OF BACTERIAL

CONJUNCTIVITIS: OFF LABEL INDICATION FOR

KERATITIS

Besivance® (0.6% besifloxacin) 1gt TID x 7d

Is a suspension, MUST SHAKE!

The only sole topical ophthalmic

chorofluoroquinolone

(not available systemically)

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If so, it would be considered an off label use

Alternative dosing of 4th gen. fluoroquinolones

for corneal ulcer/microbial keratitis therapy:

Loading dose of 1gt q5min x 5 doses then

1gt q30min x 4-6h, then Q1hr until F/U

Supplement with nighttime use of either: AK-PolyBac or Tobramycin ung QHS

FDA INDICATION:

“For ocular inflammation with the risk of superficial bacterial infection”

Steroid= Anti-inflammatory

Ab= provides prophylaxis against bacterial infection & will decrease bacterial overgrowth that is often the cause of the ocular inflammation

MOST POPULAR FORMULATIONSTobradex® (0.3% tobramycin,

0.1% dexamethasone) Available in both suspension

and ointment Suspension available generically Typical Dosage: q 2hour

x2 days, then QID x 5d

Tobradex ST® (0.3% tobramycin, 0.05% dexamethasone) ST=“Suspension Technology” Formulated with Xanthan Gum vehicle Increases contact time to allow equal

bioequivalence Typical Dosage: q 2hour x2 days,

then QID x 5d

MOST POPULAR FORMULATIONS

Zylet® (0.3% tobramycin,

0.5% loteprednol) Suspension only

Typical Dosage: q 2hour

x2 days, then QID x 5d

OcuSoft Original Lid Scrubs/

OcuSoft Foam Cleanser

Soaps only

OcuSoft Plus Lid Scrubs/

OcuSoft Foam Cleanser

Soaps plus disinfectant

SteriLid by TheraTearsActive Ingredient: Linalool,

a plant oil with antibacterial propertiesalso has melaleuca (tea tree oil)

Avenova

Active ingredient: 0.01% Hypochlorous Acid

High kill rate across Staph aureus, Staph Epi,

MRSA and Demodex

Has no additives or preservatives to limit side

effects

OcuSoft HypoChlor

Active ingredient: 0.02% Hypochlorous Acid

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Demodex Blepharitis

Demodex folliculorum: hair/lash follicles

Demodex brevis: sebaceous glands

Parasitic mites

Demodex Blepharitis

Diagnosis:

Epilate lashes and view

under microscope

Lash manipulation at slit

lamp

http://www.youtube.com/w

atch?v=16bSxfCS0wI

Treatment of Demodex

Commercial Preparations

with Tea Tree Oil (Melaleuca)Zirgan® (0.15% ganciclovir)

Ophthalmic gel only

Not generically available

Mechanism of Action:

Inhibits DNA polymerase

Less toxicity since it is activated

by viral kinases.

Spectrum of Activity:

herpes simplex viruses and

some serotypes of adenovirus

Dosage of Zirgan for Epithelial Simplex Keratitis

5x/d until re-epithelialized, then TID x 7days

STEROIDS ARE

CONTRAINDICATED!!

Aim 1: In Tx of simplex epithelial keratitis,

does adding oral acyclovir to topical antiviral

prevent stromal or uveitis

→NO

Aim 2: In Tx of simplex epithelial keratitis,

does adding oral acyclovir to topical antiviral

prevent recurrences

→YES

Aim 3: Study the role of external factors in

the induction of recurrence of simplex

keratitis → No published results yet

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Dosages for Simplex Recurrence Prevention

(HEDS II):

Acyclovir 400mg BID for 1 year

Valtrex 500mg QD for 1 year

Famvir 250mg BID for 1 year

Aim 1: In Tx of stromal herpetic disease, does adding topical steroids to topical antiviral improve outcome →YES

Aim 2: In Tx of stromal herpetic disease, does adding oral acyclovir to topical steroids & topical antiviral improve outcome →NO***

Aim 3: In Tx of simplex uveitis, does adding oral acyclovir to topical steroids & topical antiviral improve outcome →YES

Topical Treatment (Primary Therapy): Zirgan QID

Lotemax or Pred Forte QID

Oral Treatment (Supplemental Therapy):

Acyclovir 400mg 5x/d x 7d

Valtrex 500mg TID x 7d

Famvir 250mg TID x 7d

Epidemic Keratoconjunctivitis

Caused by specific adenovirus serotypes 8,

19, & 37 Particularly low levels of natural immunity to these

strains

Very contagious

Wide range in symptoms

In office method to detect adenovirus

Anesthetic does not interfere with results

Swab the conjunctiva 6-8 times

Test results in 10 minutes

Detects all serotypes

89% Sensitivity

94% Specificity

CPT code 87809

Off label treatment

Those treated with Zirgan resolved in 7.7

days compared to 18.5 days in control group.

Tx group 22% developed SEIs

Control group 77% developed SEIs

Tabbara KF, Goldschmidt PL, Nobrega R. Ganciclovir effects in adenoviral

keratoconjunctivitis. Poster 3111-B253. Presented at ARVO; Fort Lauderdale, FL 2001

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OPHTHALMIC BETADINE= 5% Povidone-Iodine

1.1 gt 0.5% Proparacaine

2.2 gt topical NSAID

3.4-6 drops Ophthalmic Betadine Solution

4.Close eyes and roll around for 60-90 sec

5.Rinse with sterile saline

6.2gt topical NSAID

7.Lotemax QID x 4days

Current Phase 3 trial of effectiveness of

combo agent of 0.6% Povidone Iodine & 0.1%

dexamethasone for the treatment of:

Bacterial Conjunctivitis

Adenoviral Conjunctivitis

Only prescribe when indicated

Use the right drugs for the right bugs

Avoid sublethal dosing

Have patients continue their course of Tx for

the full duration to ensure that all microbes

are killed

Thank You!