Neonates encephalitis

Picornavimses are small, nonenveloped RNA vimses. Members of this family include rhino- and enteroviruses, which are responsible for a variety of human diseases (viral respiratory infection, viral meningitis, myocarditis, pericarditis, encephalitis, chronic meningoencephalitis, herpangina, otitis media, neonatal enteroviral disease, and acute exacerbations of asthma). 

Oral acyclovir is useful in the treatment of HSV-1 and HSV-2 infections, such as genital herpes, herpes encephalitis, herpes keratitis, herpes labialis, and neonatal herpes. In initial episodes of genital herpes, oral acyclovir has been found to reduce viral shedding, increase the speed of healing of lesions, and decrease the duration of pain and new lesion formation. Acyclovir appears to be less effective in the treatment of recurrent herpes genitalis but may be used for the long-term suppression of recurrent HSV. 

Intravenous acyclovir is used in the treatment of herpes simplex encephalitis, neonatal HSV infection, and mucocutaneous HSV infection in immunocompromised individuals. Acyclovir ointment is used in the treatment of initial genital herpes but is not effective for recurrent disease. Ophthalmic acyclovir formulations, although not available in the United States, are effective in the treatment of herpes keratoconjunctivitis. 

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 VZV infection, intravenous acyclovir reduces the incidence of cutaneous and visceral dissemination. 

Indications PO - acute treatment of herpes zoster (shingles) Initial episodes and the management of genital herpes Treatment of chickenpox (varicella) IV - treatment of initial and recurrent mucosal and cutaneous herpes simplex (HSV-1 and HSV-2) in immunocompromised patients Treatment of herpes simplex encephalitis Treatment of neonatal herpes infections Treatment of varicella-zoster (shingles) infections in immunocompromised patients... 

Herpes Simplex Virus Ophthalmia Neonatorum. HSY infection is an uncommon but important cause of neonatal infection and is associated with conjunctivitis in 5% to 10% of cases.The clinical manifestations are nonspecific and include conjimctival hyperemia, chemosis, periorbital edema, and mucous discharge. Corneal involvement is not uncommon and can include dendritic, geographic, or stromal keratitis. Herpetic ophthalmia neonatorum represents a primary herpetic infection. Central nervous system involvement, encephalitis, retinitis, optic neuritis, uveitis, choroiditis, and a fetal viremia can be serious sequelae of primary herpetic infections. 

Parenteral acyclovir is the drug of choice for the treatment of initial and recurrent mucosal or cutaneous herpes simplex infections in immunocompromised patients and for the treatment of disseminated, neonatal, encephalitic, and severe first episodes of genital herpes simplex infections in immunocompetent patients (Whitley, 1997). Intravenous acyclovir should also be used for severe diseases such as encephalitis (Brady and Bernstein, 2004). 

Seizures occur more infrequently in horses than in dogs and cats. Seizures are seen in adult horses from brain trauma, bacterial meningitis, viral encephalitis and, rarely, hepatic encephalopathy or vascular accidents. Convulsions are seen in young neonatal foals with NMS as a result of brain hypoxia and in Arabian foals aged 3-9 months (idiopathic Arabian epilepsy). Anticonvulsant therapy is used to prevent the spread of the seizure focus, increase (raise) the seizure threshold and decrease the electrical excitement of abnormal... 

Neonatal HSV infection occurs in 1 3500 to 1 5000 deliveries in the United States. It is most commonly acquired by intrapartum contact with infected maternal genital secretions and is usually caused by HSV type 2. In tlie newborn there are three general presentations of the disease skin, eye, and mouth disease accounts for approximately 45% of infections, encephalitis accounts for 35%, and disseminated disease accounts for 20%. As disseminated disease is often associated with neurological disease, CNS disease occurs in about 50% of newborns with neonatal HSV infection. 

Secondary infection of lesions extragenital infection due to autoinoculation disseminated infection (primarily in immuncompromised patients) meningitis or encephalitis neonatal transmission... 

Vidarabine, an antiviral agent (10 to 15 mg/kg/day for 5 to 10 days), is indicated in the treatment of herpes simplex virus encephalitis, neonatal herpes simplex virus infections, and herpes zoster in immunosuppressed patients. In addition, vidarabine (ophthalmic ointment 3% vidarabine monohydrate [equivalent to 2.8% vidarabine]) is indicated in the treatment of acute keratoconjunctivitis and recurrent epithelial keratitis due to herpes simplex virus types 1 and 2, or superficial keratitis caused by herpes simplex virus that has not responded to topical idoxuridine or when toxic or hypersensitivity reactions to idoxuridine have occurred. 

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. 

It was concluded previously (11) that FMAU is a most potent and selective antiviral compound for the treatment of mouse encephalitis caused by HSV-2 and therefore deserved consideration as a potential agent in human trials for the treatment of HSV encephalitis in neonates and adults at low dose levels. The preliminary data described in Tables I and II for FEAU suggested (10) that this compound may also be worthy of similar consideration. Based upon these earlier findings (10) and on our preliminary biochemical report (12). further comparative biochemical and antiviral studies were undertaken with FMAU and FEAU, including their relative activities against Simian varicella vims in the African green monkey and against hepatitis vims in the woodchuck animal model. In these studies (13) an alternative synthesis of FEAU is also described. 

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