Post-traumatic-Infectious

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Post-traumatic Infectious
Endophthalmitis
Ghanbari MD
1391:03:25
CORNEA & RETINA
FRIENDS …. OR FOES …..?
The extent of wound
Described as:
• Zone I : limited to the cornea and limbus;
• Zone II : Involves the anterior sclera within
5 mm from the limbus;
• Zone III : Involves sclera posterior to 5 mm
from the limbus
• An open globe injury is a full thickness
laceration of the cornea and/or sclera, either
penetrating (one entrance wound) or
perforating (an entrance as well as an exit
wound).
• Post-traumatic infectious endophthalmitis is
an uncommon but severe complication of
ocular trauma.
Incidence and epidemiology
• Post-traumatic endophthalmitis comprises
approximately 25--30% of all cases of
infectious endophthalmitis
• The reported incidence of endophthalmitis
following open globe trauma ranges from
3.1% to 11.9% of open globe injuries in the
absence of an IOFB.
• The incidence in cases with an IOFB ranges
from 3.8% to 48.1%, with higher infection
rates reported in eyes with retained IOFBs
contaminated with organic matter from a
rural setting.
Signs and Symptoms
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Pain ,
Decreased visual acuity,
Photophobia,
Tearing,
Pain with eye movement.
• Pain from trauma may be distinguished
from that of endophthalmitis if it is out of
proportion to the degree of injury.
Clinical signs of infection
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Purulent exudate from the site of injury,
Eyelid edema,
Chemosis,
Corneal edema,
Hypopyon,
Other signs
• Severe anterior chamber inflammation(e.g.,
fibrinoid response);
• Vitritis or vitreous opacification;
• Retinitis ;
• Periphlebitis.
RAPD
• Inflammation that progresses slowly
following primary repair may be indicative
of fungal endophthalmitis.
• These patients usually have minimal
discomfort in contrast to the intense pain
associated with bacterial infection.
• The clinician should consider the diagnosis
of endophthalmitis in all eyes with a history
of trauma as the time between the injury
and the onset of symptoms can be highly
variable.
• Signs and symptoms of endophthalmitis may
occur days, weeks, months, and even years
after the injury.
Diagnosis:
• Symptoms of extreme pain with hypopyon
and vitritis indicate an infection until
proven otherwise.
• If the signs are subtle, diagnosis can be
difficult.
• An increase in inflammation with increase
in pain and vitritis should prompt an
investigation for endophthalmitis.
• During the initial assessment of all types of
penetrating ocular trauma, especially if
there is a suspicion of endophthalmitis, the
eye should be Evaluated for the presence of
an IOFB.
• Unfortunately, media opacities, hypopyon,
fibrin membranes, vitritis, vitreous
hemorrhage, and/or traumatic cataract can
make it difficult to visualize an IOFB
directly.
• Plain radiography and computed
tomography scans are then used to detect
IOFBs.
• In order to detect small objects by
computed tomography, the cut width should
be less than 2 mm.
B-scan ultrasound
• May be used to help locate radiolucent
foreign bodies such as glass or plastic.
Risk factors for the development of
post-traumatic endophthalmitis
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Retained IOFB,
Lens rupture,
Delayed timing of primary repair,
Age greater than 50 years,
Female gender,
Large wound size,
Location of wound,
Ocular tissue prolapse,
Placement of primary intraocular lens (IOL),
Rural locale.
• The composition of the IOFB may play a
role in infection;
Non-metallic IOFBs may have a higher risk
of endophthalmitis.
• Delayed primary repair, especially more
than 24 hours, is considered to be a risk
factor for post-traumatic endophthalmitis in
the absence of an IOFB.
Nature of Trauma
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Organic vs Inorganic Injury;
Penetrating vs Perforating Injury;
High- vs Low-velocity Projectile Injuries;
Wound Site;
Intraocular Tissue Prolapse.
• Posterior scleral lacerations commonly are
associated with vitreous and uveal prolapse.
Traditionally, the presence of intraocular
tissue prolapse through the open wound has
been thought to increase the risk of
endophthalmitis through enhanced
exposure to infecting organisms.
Factors affecting visual
prognosis
• The visual prognosis in traumatized eyes
with endophthalmitis is extremely poor.
Factors affecting visual prognosis
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The presence of an RAPD,
Perforating injury, expelled lens,
Corneoscleral wound (vs corneal wound),
Retinal detachment at the time of injury.
Virulence of Microorganisms
• Cases of traumatic endophthalmitis that
involve Bacillus cereus, either as the sole
causative agent or as one of many, have a
very high risk of progressing to a final
visual acuity of NLP.
• Eyes with Gram negative rod infection also
tend to lose vision quickly.
• Fungal infections can be difficult to
diagnose, which delays the treatment.
Surprisingly, good vision can be achieved in
the fungal cases.
• On the other hand, Staphylococcus
epidermis, which is the most common
organism noted in such infections, is not as
virulent as Gram-negative or Bacillus
infections, and many more eyes achieve a
final visual acuity of 20/400 or better if the
nature of the injury permits them to do so.
Characteristics of Intraocular
Foreign Bodies
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1) Structural damage induced by the IOFB
(e.g., retinal tear);
2) Vehicle to deliver infectious agent(s);
3) Chemistry of the IOFB (e.g., pure copper
is very inflammatory).
Vitreous Tap or Biopsy
• Once the diagnosis of post-traumatic
endophthalmitis is suspected, a vitreous tap
or biopsy should be done promptly so that
the specimen can be sent for Gram stain,
culture, and KOH stain.
Management
a. Treatment guidelines for posttraumatic
endophthalmitis
• Intravitreal Antibiotic Therapy:
• For initial therapy, intravitreal vancomycin
hydrochloride (1 mg/0.1 ml normal saline)
and ceftazidime (2.25 mg/0.1 mL normal
saline) unless the patient is allergic to the
medication(s).
• Currently, vancomycin is the drug of choice
for Gram-positive organisms including
Staphylococcus and Streptococcus species.
• The half life of vancomycin in the vitreous
of infected rabbit eyes is long (38 -54 hours).
IV Antibiotic Therapy
• There are several options for intravenous
antibiotic therapy
• One vancomycin intravenous (1 gram every
12 hours in patients with normal renal
function)
• Ceftazidime (1 gram every 8 hours).
• Additional treatment with intravenous
clindamycin (300 mg every 8 hours) can be
considered in a scenario when vancomycin
is contraindicated
• Or if Bacillus or anerobic infections such as
Clostridium are suspected.
• Topical antibiotics are almost always used
with intravitreal antibiotics for
endophthalmitis treatment in an attempt to
increase the antibiotic concentration in the
eye.
• Topically administered antibiotics have poor
penetration into the vitreous cavity.
• Fortified topical antibiotics may be used
while awaiting culture results and include
vancomycin hydrochloride (50 mg/mL) with
ceftazidime (100 mg/mL) every hour.
• Fortified gentamicin sulfate or tobramycin
(14 mg/mL) can also be used with cefazolin
sodium (50 mg/mL) if vancomycin and
ceftazidime cannot be used
Topical and Subconjunctival
Antibiotics
• Subconjunctival administration of
antibiotics can lead to therapeutic levels
especially in the anterior chamber.
• This approach can be used in patients where
frequent drops cannot be administered.
Subconjunctival injection
• Vancomycin hydrochloride:
(25 mg/0.5 mL of normal saline)
• Ceftazidime:
• (100 mg in 0.5 ml of normal saline)
Steroid Therapy
• Theoretically, concurrent administration of
corticosteroids may be beneficial in
bacterial endophthalmitis to control both
inflammation- and infection-related tissue
injury.
Treatment of Post-traumatic Fungal
Endophthalmitis
• The most common organism reported in
posttraumatic fungal endophthalmitis is
Candida albicans.
• Fusarium and Aspergillosis also have been
reported frequently in this setting.
• Intravenous amphotericin B combined with
intravitreal amphotericin B is the most
common treatment regimen used in this
setting.
• The intravitreal amphotericin dose is 5-10
µg in 0.1 mL.
• Intravenous amphotericin B can be given at
a dose of 1 mg/kg of body weight, assuming
normal renal function.
Role of Vitrectomy
• In addition to appropriate antibiotic
treatment, some clinicians feel that it is also
important for patients with post-traumatic
endophthalmitis to undergo early
therapeutic vitrectomy.
Special Considerations with IOFBs
• Prompt surgical management is imperative
if a patient presents with clinical signs and
symptoms of post-traumatic
endophthalmitis with an IOFB.
Goal
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PPV
IOFB removal,
Debridement of the infected vitreous, and
Intravitreal antibiotics injection.
IOFB culture.
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