Vaccinia keratitis

Hypersensitivity to any component of these products epithelial herpes simplex keratitis (dendritic keratitis) vaccinia varicella mycobacterial infections of the eye fungal diseases of the ocular structure use of steroid combinations after uncomplicated removal of a corneal foreign body. 

Absolute hypersensitivity to the drug or any other component of the product. Active or suspected ocular or periocular infection (herpes simplex keratitis, vaccinia, varicella, mycobacterial disease or fungal infection), systemic fungal infections, advanced glaucoma or concurrent administration of live vaccines in patients receiving immunosuppressive doses. 

Topical apphcation of ara-HxMP, C2QH23N40gP, significantly inhibited the development of keratitis-induced HSV-1, HSV-2, or vaccinia vims in the eyes of rabbits. Ara-HxMP also significantly controlled the development of HSV-1 or vaccinia viral-induced encephaUtis in mice and was also active in preventing equine abortion viral deaths in hamsters. Clinical trials with ara-HxMP have not yet been reported. 

The answer is b. (Hardman, p 1203.) Trifluridine inhibits viral activity in HSV types 1 and 2, CMV, vaccinia, and perhaps adenovirus. It acts as a viral DNA synthesis inhibitor by irreversibly blocking thymidylate synthetase. Trifluridine triphosphate is a competitive inhibitor of thymidine triphosphate accumulation into DNA It is used in the treatment of primary keratoconjunctivitis and recurrent epithelial keratitis caused by HSV 1 and 2. 

Acute epithelial herpes simplex keratitis (dendritic keratitis) fungal diseases of ocular structures vaccinia, varicella and most other viral diseases of the cornea and conjunctiva ocular tuberculosis hypersensitivity after uncomplicated removal of a superficial corneal foreign body mycobacterial eye infection acute, purulent, untreated eye infections that may be masked or enhanced by the presence of steroids. 

Efficacy In other conditions The clinical efficacy in the treatment of stromal keratitis and uveitis caused by herpes simplex or ophthalmic infections caused by vaccinia virus and adenovirus, or in the prophylaxis of herpes simplex virus keratoconjunctivitis and epithelial keratitis has not been established by well-controlled clinical trials. Not effective against bacterial, fungal, or chlamydial infections of the cornea or trophic lesions. 

Contraindications Hypersensitivity to ciprofloxacin or other quinolones for ophthalmic administration vaccinia, varicella, epithelial herpes simplex, keratitis, mycobacterial infection, fungal disease of ocular structure, use after uncomplicated removal of a foreign body... 

Trifluridine (trifluorothymidine) is a fluorinated pyrimidine nucleoside that inhibits viral DNA synthesis in HSV-1, HSV-2, CMV, vaccinia, and some adenoviruses. It is phosphorylated intracellularly by host cell enzymes, and then competes with thymidine triphosphate for incorporation by the viral DNA polymerase (Figure 49-3). Incorporation of trifluridine triphosphate into both viral and host DNA prevents its systemic use. Application of a 1% solution is effective in treating keratoconjunctivitis and recurrent epithelial keratitis due to HSV-1 or HSV-2. Cutaneous application of trifluridine solution, alone or in combination with interferon alfo, has been used successfully in the treatment of acyclovir-resistant HSV infections. 

Recent work has centered upon use of interferon as a therapeutic agent in humans and animals. In humans, local application of monkey interferon is effective in reducing the seventy of vaccinia virus skin infections. Recent results with herpes keratitis and chronic hepatitis are promising. Interferon appears to be active against oncogenic viruses in the treatment of such cancers as osteogenic sarcoma, and at present it is only the limited availability of interferon that pie vents more extensive testing. 

The diagnosis of herpes simplex disciform keratitis is usually based on clinical appearance. If a history of previous episodes, ghost scars, or decreased corneal sensation is found, herpes simplex is the likely cause, but it is important to rule out other etiologies such as herpes zoster, varicella, vaccinia, mumps, and syphilis. 

Vaccinial lesions on the eyelids and the conjunctivae are seen after secondary infection with Vaccinia virus by scratching (42,43). From these lesions a keratitis can develop, which sometimes extends to deeper layers of the cornea, with concomitant iridocychtis. Papillitis with myelitis has been described after revaccination (44). 

Idoxuiidlne, USF. Idoxuridinc. S-iodo-2 -dcoxyuridine (Stoxil, Herplex), was introduced in 1963 for the treatment of herpes simplex keratitis. - The drug is an iodinated analogue of thymidine that inhibits replication of a number of DNA viruses in vitro. The susceptible viruses include the herpesviruses and poxviruses (vaccinia). 

Vaccinia immune globulin IV is a vaccinia-specific immunoglobulin G (IgG), which directly neutralizes vaccinia virus. It is indicated in treatment and/or modification of aberrant infections induced by vaccinia virus (including accidental implantation in eyes, mouth, or other areas where vaccinia infection would constitute a special hazard), eczema vaccinatum, progressive vaccinia, severe generalized vaccinia, and vaccinia infections in individuals who have skin conditions such as bums, impetigo, varicella-zoster, or poison ivy, or in individuals with eczematous skin lesions. Treat complications that include vaccinia keratitis with caution. 

Vidarabine is used mainly in human HSV-1 and HSV-2 encephalitis, decreasing the mortality rate from 70 to 30%. Whitley et al. (57) reported that early vidarabine therapy is helpful in controlling complications of localized or disseminated herpes zoster in immunocompromised patients. Vidarabine also is useful in neonatal herpes labialis or genitalis, vaccinia virus, adenovirus, RNA viruses, papovavirus, CMV, and smallpox virus infections. Given the efficacy of vidarabine in certain viral infections, the U.S. FDA approved a 3% ointment for the treatment of herpes simplex keratoconjunctivitis and recurrent epithelial keratitis, and a 2% IV injection for the treatment of herpes simplex encephalitis and herpes zoster infections (Table 43.3). A topical ophthalmic preparation of vidarabine is useful in herpes simplex keratitis but shows little promise in herpes simplex labialis or genitalis. The monophosphate esters of vidarabine are more water-soluble and can be used in smaller volumes and even intramuscularly. These esters are under clinical investigation for the treatment of hepatitis B, systemic and cutaneous herpes simplex, and herpes zoster virus infections in immunocompromised patients. 

Vaccinia-immune globulin (VIG) is of value in the treatment of progressive vaccinia, eczema vaccinatum,97 and perhaps ocular vaccinia (VIG is discussed below in the section titled Passive Immunoprophylaxis). Topical idoxuridine may benefit vaccinia keratitis.98 99... 

A comparison of 1-p-D-arabinofuranosylcytosine and 1-P-D-arabinofuranosyl-5-fluorocytosine as inhibitors of herpes keratitis infection in rabbits and of vaccinia in tissue culture indicated comparable activity. The compound,... 

Vlrazole, a -D-rlbofuranosyl derivative, has demonstrated a broad spectrum of in vitro inhibitory activity against adenovirus, HSV I and II, vaccinia, myxoma virus, parainfluenza, rhinovirus, Coxsackie virus and influenza A and B,91 it is more potent than other antl-lnfluenzal compounds in vitro and is effective against HSV keratitis and localized vaccinia. Friend leukemia virus, influenza A and parainfluenza I in vivo. The antiviral effect may be due to the inhibition of guanosine-T -phosphate synthesis in the infected cell. ... 

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