Herpes zoster, disseminated

Hand, foot, and mouth disease Herpes zoster, disseminated Leukemia - acute Measles... 

Valacyclovir demonstrates efficacy similar to that of acyclovir but requires less frequent oral dosing. While indicated for the treatment of herpes zoster and the treatment and suppression of HSV, it is not approved for use in immunocompromised individuals or for the therapy of disseminated herpes zoster. 

The most common cause of primary demyelination is MS, so demyelinating optic neuropathy is often associated with MS. Other conditions have been implicated in demyelinating optic neuropathy, including acute transverse myelitis, acute disseminated encephalomyelitis, herpes zoster, Gnillain-Barre syndrome, Devic s nemomyelitis optica, Epstein-Barr virus, Charcot-Marie-Tooth syndrome, and chronic multifocal demyelinating nemopathy. 

Therapy for herpes zoster should be aimed at accelerating healing, limiting the severity and duration of acute and chronic pain and reducing any complications associated with the infection. In patients who are immunocompromised, therapy should also be aimed at reducing the risk of viral dissemination. Acyclovir, valacyclovir, and famciclovir are all used in the United States for the treatment of herpes zoster. Acyclovir is approved in the U.S. for the treatment of both chickenpox and herpes zoster in the normal host. Oral acyclovir therapy in normal children, adolescents, and adults shortens the duration of lesion formation by about a day, reduces the total number of new lesions by abont 25%, and reduces many of the symptoms in abont a third of patients (Gnann and Whitley, 2002 Snoeck et al., 1999). 

Up to 50% of all patients surviving up to 10 months after transplantation develop an infection caused by VZV. Infection with VZV is most common in patients receiving allogeneic transplants with acute or chronic GVHD. Both primary (varicella) or recurrent disease (herpes zoster) usually present as skin lesions, most of which remain contained to local areas however, 30% to 45% of these infections may disseminate to other cutaneous areas or body organs, causing mortality as high as 50%. " ... 

In immunocompromised patients with herpes zoster, intravenous acyclovir (500 mg/rrP every 8 hours for 7 days) reduces viral shedding, healing time, risks of cutaneous dissemination and visceral complications, and the length of hospitalization. In immunosuppressed children with varicella, intravenous acyclovir decreases healing time and the risk of visceral complications. 

Clinical use and toxicity Interferon alpha is approved for use in chronic hepatitis A and B infections, Kaposi s sarcoma, papillomatosis, and topically for genital warts. Another possible use of interferons is to prevent herpes zoster vims dissemination in cancer patients. Toxic effects include dose-limiting neutropenia, gastrointestinal irritation, fatigue, myalgia, mental confusion, and a reversible cardiomyopathy. 

A) Interferons may prevent dissemination of herpes zoster in cancer patients and reduce CMV shedding after renal transplantation... 

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. 

Influenza, varicella, vaccinia, disseminated herpes zoster. 

Aksoy B, Altaykan-Hapa A, Cengiz A, Mete Aksoy H, Atakan N. Disseminated cutaneous herpes zoster complicated by acyclovir nephrotoxicity and successfully treated with brivudin. Eur J Dermatol 2010 20(2) 247-8. 

In a retrospective study of rheumatoid arthrihs pahents treated with leflunomide risk factors of severe infections were identified. Among the 401 patients that started on leflxmomide therapy, 8.2% developed severe infections (pneumonia, oral candidiasis, pyelonephrihs, pulmonary tuberculosis, cellulitis, disseminated herpes zoster, tonsil-lihs and pulmonary cryptococcosis). Risk factors for severe infections were older age, presence of diabetes mellitus and (increasing) daily dosage of corticosteroids [Sl ]. 

Intravenous acyclovir is the treatment of choice for herpes simplex encephalitis, neonatal HSV infection, and serious HSV or VZV infections (Table 49-1). In immunocompromised patients with zoster, intravenous acyclovir reduces the incidence of cutaneous and visceral dissemination. 

Disseminated infection with Herpes simplex vims and Varicella zoster vims occurred in a patient taking thalidomide for relapsed multiple myeloma (95). 

Ocular antiviral chemotherapy in the horse is adapted from that used in herpes simplex virus (HSV) and varicella zoster keratitis in humans. The agents used are nucleotide analogs capable of inhibiting viral replication by competitive inhibition of the uptake of the nucleotide into the viral genome. These agents are virustatic and require an intact immune system to suppress or eliminate the virus from the eye. They probably do not eradicate any latent infection. The antiviral drugs available currently do not penetrate intact comeal epithelium and are poorly disseminated within the comeal stroma. The availability of these dmgs will vary in different countries and some may only be obtained from hospital pharmacies. 

Nikkels AF, Delverme P, Sadzot-Delvaux C, et al. Distribution of varicella zoster virus and herpes simplex virus in disseminated fatal infections./ Clin Pathol. 1996 49 243-248. 

Vidarabine Vidarabine is an adenine analog and has activity against HSV, VZV, and CMV. Its use for systemic infections is limited by rapid metabolic inactivation and by marked toxic potential. However, it has been used intravenously for severe HSV infections, including those resistant to acyclovir, and it also prevents the dissemination of varicella-zoster virus in immunocompromised patients. Vidarabine is used topically for herpes keratitis, but it has no effect on genital lesions. Toxic effects with systemic use include gastrointestinal irritation, paresthesias, tremor, convulsions, and hepatic dysfunction. Vidarabine is teratogenic in animals. 

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