2: Herpes Flashcards
herpes simplex virus (HSV) is the leading cause of _____
infectious corneal blindness in all developed countries
HSV is categorized by _____, and further categorized by _____
viral strand;
infection- primary or recurrent
primary HSV-1 transmission
- mucosal membranes
- saliva
- tears
primary HSV-1 is highly ______;
____% of population get it by age 5, and _____% by age 60
contagious;
60;
~100
primary HSV-1 most common patient populations
school-aged children** and neonates (rare)
primary HSV-1 has a more severe presentation in _____
neonates and immunocompromised
primary HSV-1 symptoms are _____;
symptoms include:
RARE (~94% of patients are asymptomatic);
- flu-like malaise
- low-grade fever
- possible concurrent upper respiratory infection
- oropharynx > ocular
primary HSV-1 ocular clinical signs
- pre-auricular node swelling
- vesicular rash (eyelids and adnexa)
- follicular conjunctivitis
- rare: multiple corneal punctate lesions –> coalesce into epithelial dendrite
primary HSV-1: epithelial vesicles
- contain the live virus
- primary HSV-1 vesicles are limited to the epithelium
after active infection, primary HSV-1 lies latent in the _____
trigeminal and dorsal root ganglia
recurrent HSV-1 transmission
- mucosal membranes
- saliva
- tears
recurrent HSV-1 has more severe presentation in _____
children and immunocompromised
recurrent HSV-1 laterality
unilateral»_space; bilateral
ocular involving recurrent HSV-1 is also known as _____
Herpes Simplex Keratitis (HSK)
ocular involving recurrent HSV-1 (HSK) symptoms
- pain/ocular discomfort
- photophobia
- watering
- itching
- decreased vision/blurry vision
- corneal desensitization (hypoesthesia)
ocular involving recurrent HSV-1 (HSK) signs
- pre-auricular node swelling
- vesicular rash (eyelids and adnexa)
- follicular conjunctivitis
- dendritic keratitis**
- conjunctival injection
- superficial macropunctate keratitis (larger punctate areas than classic SPK)
- other anterior and posterior complications
ocular involving recurrent HSV-1 (HSK): adnexal and eyelid vesicles
clear vesicles on an erythematous base that progress to crusting (more itchy than painful)
ocular involving recurrent HSV-1 (HSK): corneal types of HSK
HSK-epithelial:
- dendritic
- geographic
- neurotrophic
- marginal
HSK-stromal:
- disciform (also is endothelial)
- immune
- necrotizing
Endotheliitis
HSK-epithelial: dendritic keratitis
- pathognomonic herpetic finding
- ulceration of the epithelium with underlying stromal thinning
- heaped, swollen epithelial cells create boundary and terminal end-bulbs
- branching/arborized appearance
HSK-epithelial: dendritic keratitis staining
- (+) stain with fluorescein in center
- (+) stain with fluoroscien (mild), rose bengal, lissamine green along boundary
HSK-epithelial: dendritic keratitis left unmanaged
unmanaged –> corneal haze, stromal infiltration –> scarring
HSK-epithelial: geographic keratitis
- dendritic may progress to geographic
- swollen, scalloped borders
HSK-epithelial: neurotrophic keratitis
- sterile ulcer
- typically in tandem with interstitial (necrotizing) keratitis
- stromal melt and corneal perforation –> “endophthalmitis”
- corneal degradation –> desnsitization –> “I got better!”
- vision threatening
HSK-epithelial: marginal/limbal keratitis
- active virus + inflammatory reaction
- peripheral ulcer –> stromal infiltrate –> limbal/corneal neo
HSK-stromal: disciform keratitis
- non-necrotizing (does not degrade the corneal tissue), immune response to residual herpetic proteins –> inflammation
- opaque or “ground glass”, disc shaped stromal and endothelial infiltration with stromal and endothelial edema
- can occur concomitantly with HSK-epithelial, can occur after HSK-epithelial
HSK-stromal: immune, stromal keratitis (SK)
- non-necrotizing stromal keratitis, aka “stromal keratitis”
- round/lobulated opaque/whitened stromal infiltration (haze and scarring)
- can occur concomitantly with HSK-epithelial, can occur after HSK-epithelial
HSK-stromal: necrotizing, interstitial keratitis (IK)
- less common, more severe
- white/gray opaque stromal infiltration with necrosis and ulceration, stromal edema, possible abscess, corneal neovascularization
- may also have concomitant uveitis, hypopyon, trabeculitis (inflammatory increase in IOP)
- unmanaged IK –> neurotrophic ulcer, corneal perforation
- high risk of vision loss
HSK-endothelial: endotheliitis
- endothelial keratitis
- typically in tandem with HSK-stromal involvement, especially disciform
- presents with endothelial folds, endothelial edema, stromal edema, may include keratic precipitates
- concomitant uveitis, trabeculitis (increased IOP)
- high risk of vision loss
recurrent HSV-1 (HSK) complications
- corneal hypoesthesia (especially with corneal involvement)
- uveitis: anterior, intermediate, posterior, panuveitis; typically in tandem with SK, IK, or endotheliitis; AC rxn (mild to severe), granulomatous KPs, elevated IOP; iris atrophy, posterior synechiae, secondary angle closure (trabeculitis)
- scleritis > episcleritis
- retinitis, acute retinal necrosis (ARN): neonates, immunocompromised, concurrent HIV/AIDS infection; severe, bilateral, rapid progression
- optic neuritis: optic nerve edema, typically in tandem with retinal necrosis
varicella zoster virus (VZV) categorization
categorized by infection: primary or recurrent
primary VZV
- chicken-pox
- childhood condition
- largely declined since introduction of the varicella vaccination in 1995
recurrent VZV
- shingles
- elderly > adult condition
- can occur at any age, but typically 60-80 years
VZV laterality
ALWAYS unilateral*
after primary infection, VZV lies dormant in ____
trigeminal ganglion
3 stages of reactivated VZV
1) prodrome (pre-eruptive)
2) active virus outbreak (acute eruptive, active HZO)
3) post-herpetic neuralgia (chronic neuropathy)
reactivated VZV prodrome symptoms
more common:
- headache
- fever
- malaise
- bodily tingling, burning, pain
- blurred vision, ocular irritation, photophobia
less common:
- moodiness
- depression
- insomnia
*prodrome symptoms may carry over with the active viral outbreak
reactivated VZV outbreak
- aka: shingles
- erythematous rash –> erupts into crusty, scaly vesicular lesions; follows trigeminal dermatome pattern; ALWAYS respects facial midline*; may involve scalp, face, ear, neck, torso, arms, legs; intensely painful!
- Hutchinson’s sign: vesicular eruptions on tip of the nose; still respects facial midline; signals nasociliary nerve involvement –> higher risk of ocular involvement
- ocular complications (HZO)
herpes zoster ophthalmicus (HZO)
- 10-20% of all shingles patients
- VZV reactivation along the ophthalmic branch of the trigeminal nerve; HZO linked to weakening T-cell immunity of elderly and immunocompromised pts
herpes zoster ophthalmicus (HZO) symptoms and signs
- blurred vision
- ocular irritation
- photophobia
- redness
- tearing
- painful unilateral vesicular rash (look at scalp, forehead, ear, behind ear, adnexa, eyelids, cheek, nose)
- periorbital edema
- ptosis (from edema)
- corneal involvement
herpes zoster ophthalmicus (HZO) corneal involvement
- pseudodendrite*
- superficial punctate keratitis (SPK)
- disciform stromal keratitis, immune stromal keratitis (SK), necrotizing/interstitial keratitis (IK), endotheliitis
- neurotrophic ulcer
- neovascularization, corneal thinning, corneal opacification
pseudodendrite
- elevated mucosal plaque, “painted on” appearance
- not a true epithelial ulcer
- less vibrant/less complete staining with fluorescein
- expect minimal to no rose bengal or lissamine green staining
- no terminal endbulbs; tapered lines
- may also present with filaments
VZV/HZO complications
- uveitis: anterior, intermediate, posterior, panuveitis; AC rxn (mild to severe), granulomatous KPs; iris atrophy, posterior synechiae, trabeculitis –> increased IOP
- scleritis: anterior and posterior
- retinitis/choriditis: slight increased predilection to involve choroid over HSV
- optic neuritis
- brain and orbit: CVA/ischemic damage; orbital apex syndrome
orbital apex syndrome
- paralysis of CN II, III, IV, VI, ophthalmic branch of CN V
- optic nerve atrophy, permanent visual loss even with restoration of EOM movement and reduction of orbital inflammation with systemic steroids
post-herpetic neuralgia (PHN)
- develops if recurrent VZV is unmanaged
- ~72 hour window to initiate appropriate treatment
- severely painful nervous condition
- can last months to years post active infection
- # 1 cause of suicide in patients with chronic pain >70 years old
VZV prevention
- varicella vaccine: “chicken-pox” vaccine, 1995
- Zostavax: 2006, no longer vaccination of choice for shingles
- Shingrix: 2017, proven greater efficacy than Zostavax at shingles prevention
- reduced risk of VZV complications
- 90% effectivity in prevention of shingles AND PHN ages 50-70
- 85% for 70+
- approved for 50+
- 2 doses separated by 2-6 months
- not approved for immunocompromised or those receiving chemo/radiation
- may receive even if had Zostavax vaccine previously
- may receive if had shingles previously, just not during active infection
oral antiviral doses for HSK
- acyclovir: 400 mg 5x/day PO x7-10 days
- valacyclovir: 500 mg tid PO x7-10 days
- famciclovir: 250 mg tid PO x7-10 days
oral antiviral doses for VZV/HZO
- acyclovir: 800 mg 5x/day PO x7-10 days
- valacyclovir: 1000 mg tid PO x7-10 days
- famciclovir: 500 mg tid PO x7-10 days
oral antivirals for prophylaxis
- acyclovir: 400 mg bid
- valacyclovir: 500 mg qd
- famciclovir: 250 mg bid
reasons for prophylaxis tx of herpes
- multiple recurrences of any type of HSV keratitis, especially HSV stromal keratitis
- recurrent inflammation with scar/vascularization approaching visual axis
- more than one episode of HSV keratitis with ulceration
- post-keratoplasty performed for HSV-related scarring/astigmatism
- postoperatively in patients with a history of HSV ocular disease undergoing any type of ocular surgery or laser procedure
- in patients with a history of HSV during immunosuppressive treatment
intravenous antivirals for herpes
- for immunocompromised or sight threatening disease
- more common for posterior segment complications or patients with concurrent HIV/AIDS, CMV
