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3) A 60-year-old man complains of left eye pain and photophobia. On examination there is an erythematous rash of the periorbital skin and forehead on the left side. You also note erythema and a small vesicle on the tip of the patient’s nose. His ipsilateral conjunctiva is injected and after staining the affected eye with fluorescein, Wood’s lamp examination reveals corneal uptake in a fine branching pattern.

What is the most appropriate therapy for this patient?

A) Oral acyclovir 800mg three times a day for 7-10 days
B) Oral valacyclovir 500 mg three times a day for 7 days
C) Oral famciclovir 500mg three times a day for 7 days
D) Oral prednisolone, 40mg daily for 7 days
E) Topical acyclovir, 5 times a day until resolution of ocular symptoms

Explanation will be posted soon....
 

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This question is wrong

This question is wrongly written.
Because none of the options is correct.

Here's what's said about treatment of dendritic keratitis in emedicine
Antiviral therapy, topical or oral, is an effective treatment of epithelial herpes infection. Either topical trifluridine 1% solution 8 times daily or vidarabine 3% ointment 5 times daily has equal efficacy in treating a dendritic ulcer; however, trifluridine is more effective than vidarabine for treatment of a geographic ulcer. Response to topical therapy usually occurs in 2-5 days, with complete resolution in 2 weeks. Corneal toxicity is a frequent adverse effect of topical antiviral agents. Therefore, topical therapy should be tapered rapidly after initial response and discontinued after complete healing, generally within 10-14 days. Failure of epithelial healing after 2-3 weeks of antiviral therapy suggests epithelial toxicity, neurotrophic keratopathy, or, rarely, drug-resistant strains of HSV. Vidarabine is often effective against HSV strains that are resistant to trifluridine and acyclovir.Oral acyclovir (2 g/d) has been reported to be as effective as topical antivirals for infectious epithelial keratitis with the added advantage of no ocular toxicity. The use of systemic acyclovir is increasingly preferred over topical agents in the treatment of HSV keratitis, particularly for patients with preexisting ocular surface disease who are at high risk for toxicity from topical medications, for patients who are immunocompromised, and for pediatric patients. Newer oral antiviral drugs, such as valacyclovir and famciclovir, further simplify the dosing regimens; however, the optimal dose for ocular disease has not been determined.

Here's a picture by the way
1189694-1194268-793.jpg
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Wait a minute, it is correct:

The correct answer is choice C for sure! not sure about the reference you posted for HZO but I would see the following, nothing wrong with the question.

SAAD SHAIKH, M.D., and CHRISTOPHER N. TA, M.D., Evaluation and Management of Herpes Zoster; Am Fam Physician. 2002 Nov 1;66(9):1723-1730.

Check it out and tell me if you agree?

Thanks.
 

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Straight from emedicine as well:

Both famciclovir and valacyclovir (500 mg tid) have been shown to be as effective as acyclovir (800 mg 5 times a day) in the treatment of herpes zoster and reduction in complications.10,11 These medications have simpler dosing regimens than acyclovir, which may increase patient compliance. The standard duration of antiviral therapy for HZ is 7-10 days.

http://emedicine.medscape.com/article/783223-overview
 

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Straight from emedicine as well:

Both famciclovir and valacyclovir (500 mg tid) have been shown to be as effective as acyclovir (800 mg 5 times a day) in the treatment of herpes zoster and reduction in complications.10,11 These medications have simpler dosing regimens than acyclovir, which may increase patient compliance. The standard duration of antiviral therapy for HZ is 7-10 days.

http://emedicine.medscape.com/article/783223-overview
You know what... I think you are right :eek:
 

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famciclovir and valacyclovir are more effective than acyclovir in treating postherpetic neuralgia
famcyclovir converts to pencyclovir in body with more concentration in cell than acyclovir and same mechanism
 

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Hey guys, I signed up their site and they give you answers for 60 questions.

Here it is:

The correct answer is choice C

This patient has herpes zoster ophthalmicus, a condition caused by a reactivation of a latent infection with the varicella-zoster virus (VZV). The initial infection is a benign febrile illlness (chickenpox). Following this infection, the VZV can remain dormant in the dorsal root ganglion for many years until a decline in the patient's immune response due to aging, stress, poor nutrition, or immuno-suppressive illness or therapy allows a reactivation of the virus producing herpes zoster (shingles). In herpes zoster ophthalmicus, the virus is released from the trigeminal ganglion, travels down the ophthalmic division of the nerve to the nasociliary nerve where the nerve divides to innervate the surface of the globe and the skin of the nose down to its tip. Manifestations include a localized vesicular rash along the dermatomal distribution of the nerve which respects the midline, dermatomal pain, conjunctivitis, episcleritis and scleritis, decreased corneal sensation, a punctate keratitis which can develop into a dendritic keratitis that stains with fluorescein or rose bengal, and uveitis which can cause photophobia.

The mainstay of treatment for herpes zoster ophthalmicus are oral antiviral agents. Oral acyclovir, 800mg 5 times a day for 7-10 days, has been shown to reduce the duration and severity of symptoms as well as reduce the incidence and severity of complications. Other antiviral agents which have been shown to be equally safe and effective for herpes zoster ophthalmicus are valacyclovir and famciclovir, whose more favorable pharmacokinetic profiles and simpler dosing regimens make them the current preferred antiviral over acyclovir. Valacyclovir is given at 1000 mg 3 times a day for 7 days or Famciclovir, is given at 500mg 3 times a day for 7 days.

Some studies have shown that the use of oral steroids, choice D, when used in combination with an antiviral, provided some benefit in reducing the incidence and severity of acute pain but showed little benefit in preventing post-herpetic neuralgia. Though corticosteroids may be used in patients over the age of 50, they should be used with caution in patients with comorbid conditions such as diabetes or gastritis, and only in conjunction with an oral antiviral.

Systemic antiviral therapy has largely replaced topical antiviral preparations, choice E, for treating ocular complications of herpes zoster ophthalmicus and should not be used routinely without consultation with an ophthalmologist.
 

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oh my. i picked C but because i thought it was CMV retinitis. :eek:
thanks guys!! loved the argument fwded. great discussion.
 
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