Aciclovir varicella-zoster virus

Chickenpox in infancy and shingles in adults are caused by the same varicella-zoster virus. Very rarely and almost exclusively in immunosuppressed patients, concomitant hepatitis can occur with pronounced (mainly focal) hepatocellular necrosis, sometimes even with a fatal course. (37) Leucocytic portal and periportal infiltration can spread to the blood vessels and bile capillaries. Intranuclear inclusion bodies are present (s. fig. 23.2). Diagnosis is based on increased GPT, GOT, GDH and y-GT values as well as the presence of varicella IgM antibodies alternatively, pathogens can also be demonstrated in cultures. In children, a differential diagnosis of Reye s syndrome must be considered. As therapy in a severe course, aciclovir is indicated. (38-43)... 

Aciclovir is active against Herpes simplex virus type 1 (HSV-1), HSV-2, Varicella zoster virus (VZV), Herpesvirus simiae, and to a lesser degree Epstein-Barr virus (EBV). Resistant strains of HSV can arise owing to the emergence of thymidine kinase-deficient mutants. Other forms of resistance patterns are less common (2,3). 

A 70-year-old man was given aciclovir 750 mg/ day t by slow intravenous infusion for disseminated Varicella zoster virus infection [18 ]. He developed acute renal failure (day 3 serum creatinine 265 p.mol/1 from a normal baseline) and hyponatremia (130 tnmol/1). Adclovir was withdrawn, and his renal function... 

Infection risk An immunocompetent 3-year-old girl developed encephalitis and ophthalmic herpes zoster 20 months after immunization with varicella zoster virus vaccine [29 ]. Molecular analysis confirmed that the vaccine strain was the causative agent and this was therefore a between-the-eyes adverse reaction of type 4 [30 ]. After an intravenous course of aciclovir, the child made a full recovery with no neurological sequelae. 

Vidarabine (adenine arabinoside, ara-A) is phos-phorylated in the cell to the triphosphate derivative which blocks DNA synthesis by inhibiting DNA polymerase. It is indicated for infections with herpes simplex virus and varicella-zoster however its use has to a large extend been surpassed by aciclovir. It is administered topically or intravenously. It is inactivated rapidly by adenosine deaminase which for systemic use necessitates constant infusion of the drug. Vidarabine is the least toxic of the purine analogues. Nausea and vomiting are the most frequent adverse effects and neurotoxicity may occur. 

Viral infections that occur after transplantation are not limited to the lung. Herpes simplex infections are frequent early after the procedure, manifesting as oral vesicles or ulcerations. Less frequent is genital involvement by herpes simple virus, hepatitis or encephalitis. Herpes zoster and varicella reactivate in most patients, particularly if aciclovir prophylaxis is discontinued. Occasionally, severe cerebral arteritis or pneumonia caused by this virus may occur. CMV infection is frequent after transplantation and has to be regularly monitored by antigenemia and/or PCR for early treatment avoiding CMV disease. Epstein Barr virus (EBV) infection and EBV-associated lymphoproliferative disorders have also to be tested on a regular basis, especially in transplants with in... 

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