Ophthalmology

1. T O R K R Y T H A
2 N D Y E A R R E S I D E N T
INTRACAMERAL
ANTIBIOTICS
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University of Health and Sciences

2. INTRACAMERAL ANTIBIOTICS
Intracameral injection delivers antibiotic directly to
aqueous humor in concentrations far grater than are
achieve after either topical drops or subconjunctival
injection
For endophthalmitis prophylaxis
The most common use of intracameral prophylaxis
Cephalosporin
Vancomycin
Moxifloxacin
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3. ENDOPHTHALMITIS VITRECTOMY
STUDY
94.2% of culture-positive endophthalmitis cases involved
gram-positive bacteria
Staphylococcus epidermidis (70%)
Staphylococcus aureus (9.9%)
Streptococcus (9.0%)
Other gram positive (3%)
Enterococcus (2.2%)
Gram negative (5.9%)
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4. MOXIFLOXACIN
An improved spectrum of coverage, higher potency,
delayed antibiotic resistance, better tissue penetration,
and excellent efficacy, especially against gram-positive
bacteria
Good activity against gram-negative bacteria and
improved coverage of gram-positive cocci and atypical
pathogens.
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5. CEPHALOSPORINS
Cephalosporins are divided into 4 generations.
First: gram-positive bacteria
Third- and fourth: gram-negative
Second: has a broad-spectrum antibiotic
that covers most gram-positive and gram-negative
organisms, with the exception of methicillin-resistant
Staphylococcus aureus (MRSA).
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6. CEPHALOSPORINS
Cefuroxime is a second-generation cephalosporin
Similar to other beta-lactam antibiotics, it inhibits cell-
wall synthesis.
Cefuroxime's bactericidal activity is concentration-
dependent and occurs at concentrations that are 4 to 5
times higher than the minimum inhibitory concentrations
(MICs).
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7. CEPHALOSPORINS
Cefuroxime less potent against S aureus and more
potent against S pneumoniae and S pyogenes than first-
generation cephalosporins.
Cefuroxime is active against Haemophilus influenzae;
Moraxella catarrhalis; Escherichia coli ; Proteus mirabilis
; Klebsiella ; b -lactamase-producing penicillinase-
positive and -negative strains of Neisseria gonorrhoeae ;
and the Enterobacteriaceae Salmonella , Citrobacter ,
Enterobacter , and Shigella species
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8. VANCOMYCIN
Vancomycin is a bactericidal antibiotic with virtually 100%
coverage of gram-positive endophthalmitis- causing
organisms.
In vitro studies have reported that vancomycin was
bacteriostatic for the first 6 hours and became bactericidal
only after 8 hours, a finding that is consistent with its
mechanism of action that blocks cell-wall synthesis
Ferro JF, de-Pablos M, Logro~no MJ, Guisasola L, Aizpuru F. Postoperative
contamination after using vancomycin and gentamicin during
phacoemulsification. Arch Ophthalmol 1997; 115:165–170
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9. VANCOMYCIN
Choice for serious gram-positive cocci infections when
their is resistant to multiple drugs.
Active against S epidermidis , S aureus (methicillin
sensitive and resistant), and most strains of
Streptococcus .
Also effective against the anaerobes, diphtheroids, and
the Clostridium species, including C difficile
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10. INTRACAMERAL ANTIBIOTICS
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11. EFFICACY
Espiritu et al.9
Intracameral dose for moxifloxacin 100mcg – 500mcg; in
comparison, the dose of Intracameral cefuroxime shown to
be safe and effective is 1mg, at least two times higher than
moxifloxacin.
ESCRS study confirm the clinical efficacy of Intracameral
cefuroxime against most commonly encourntered
bacterial strains in postoperative endophthalmitis
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12. COMPLICATIONS
Corneal endothelial toxicity
Toxic anterior segment syndrome (TASS): acute sterile
postoperative inflammation that can follow anterior
segment surgery.
Dilution errors are more likely when multiple steps are
required to prepare the antibiotic solution. Both anterior
and posterior segment inflammation
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13. Vigamox eyedrops (moxifloxacin 0.5%) are preservative-
free and isotonic, with a 6.8 pH and an osmolality of
approximately 290 mOsm/kg.
Because these values are similar to those of aqueous (pH
7.4, osmolality 305 mOsm./Kg.) using this topical solution
has not been associated with ocular toxicity at full strength
or with a 50:50 dilution in balanced salt solution for
intracameral injection
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15. Kowalski et al.31 also found that intracameral injection of
commercial Vigamox was nontoxic and effective in
preventing endophthalmitis from S aureus in a large trials
that evaluate the clinical efficacy of antibiotic prophylaxis
with moxifloxacin or vancomycin.
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16. REFERENCE
ESCRS Guidelines for Prevention and Treatment of
Endophthalmitis Following Cataract Surgery: Data,
Dilemmas and Conclusions 2013
Intracameral antibiotics: Safety, efficacy, and preparation
Rosa Braga-Mele, MD, David F. Chang, MD, Bonnie An
Henderson, MD, Nick Mamalis, MD, Audrey Talley-Rostov, MD,
Abhay Vasavada, MD, for the ASCRS Clinical Cataract
Committee
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