Tags: Foscarnet

Herpesviruses

The herpesvirus group of the family Herpesviridae comprises large, enveloped, double-stranded DNA viruses found in both animals and humans. They are ubiquitous and produce infections ranging from painful skin ulcers to chickenpox to encephalitis. The major members of the group to infect humans are the two herpes simplex viruses (HSV-1 and -2), cytomegalovirus (CMV), varicella-zoster virus (VZV), Epstein-Barr virus (EBV), herpesvirus 6, and the recently discovered human herpesvirus types 7 and 8. Occasionally, the simian herpesvirus, herpes B virus, has caused human disease. All herpesviruses are morphologically similar with an overall diameter of 180-200 nm. The nucleic acid core is ~ 30-45 nm in diameter, surrounded by an icosahedral capsid. The …

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Human Herpesvirus Type 6

Essentials of Diagnosis • Infant with high fever for several days; maculopapular rash after defervescence • Can be isolated in cultures of monocytes but takes 10-30 days and may be false negative • Detection of specific IgG and IgM by indirect immunofluorescence are diagnostic tests of choice • Blood or saliva PCR for HHV-6 DNA may be positive, but diagnostic significance uncertain due to intermittent excretion in asymptomatic patients • PCR positively in CSF diagnostic of encephalitis General Considerations In 1986 a human herpesvirus, now called human herpesvirus type 6 (HHV-6), was identified in cultures of peripheral blood lymphocytes from patients with lymphoproliferative diseases (Box 2). The virus, which is genetically …

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Cytomegalovirus

Essentials of Diagnosis • “Owl eye” cells in tissue biopsy, cytology • Cultured in diploid fibroblast cells • Antibody detection of those patients seroconverting or at risk for reactivation • CMV detection in blood or bodily fluids by antigenemia, PCR, or other DNA-based assays, eg hybrid capture, or by culture General Considerations A. Epidemiology. CMV is ubiquitous, and in developed countries ~50% of adults have developed antibody (Box 7). Age-specific prevalence rates show that ~ 10-15% of children are infected by CMV during the first 5 years of life, after which the rate of new infections levels off. The rate subsequently increases during young adulthood, probably through close personal contact or …

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Order Generic Zovirax (Aciclovir) No Prescription 200/400/800mg

Acyclovir: Organs and Systems Generic Name: Aciclovir (UK), Acyclovir (US, Canada) Under what local brands and in what dosages is generic Acyclovir or Aciclovir sold in pharmacies of Britain, United States, and Canada? In pharmacies of the United States, Great Britain and Canada the pharmacists offer you to buy Aciclovir (UK) or Acyclovir (US, Canada) (according to your prescription or without a prescription) under such brand names and in such strengths and dosage forms: UK US Canada Aciclovir 5% w/w Cream Aciclovir Tablets 200, 400, 800mg Aciclovir 200mg/5ml & 400mg/5ml Oral Suspension Zovirax 200mg Tablets Zovirax 800mg Tablets Zovirax Cream Zovirax Eye Ointment Zovirax IV 250mg, 500mg Zovirax Suspension Acyclovir 200mg Capsuls …

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Anti-Infective Therapy

Despite dire warnings that we are approaching the end of the antibiotic era, the incidence of antibiotic-resistant bacteria continues to rise. The proportions of penicillin-resistant Streptococcus pneumoniae, hospital-acquired methicillin-resistant Staphylococcus aureus, and vancomycin-resistant Enterococcus strains continue to increase. Community-acquired methicillin-resistant Staphylococcus aureus is now common throughout the world. Multiresistant Acinetobacter and Pseudomonas are everyday realities in many of our hospitals. The press is now warning the lay public of the existence of “dirty hospitals.” As never before, it is critical that health care providers understand the principles of proper anti-infective therapy and use anti-infective agents judiciously. These agents need to be reserved for treatable infections — not used to calm the …

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Specific Anti-Infective Agents

Antibiotics Before prescribing a specific antibiotic, clinicians should be able to answer these questions: •  How does the antibiotic kill or inhibit bacterial growth? •  What are the antibiotic’s toxicities and how should they be monitored? •  How is the drug metabolized, and what are the dosing recommendations? Does the dosing schedule need to be modified in patients with renal dysfunction? •  What are the indications for using each specific antibiotic? •  How broad is the antibiotic’s antimicrobial spectrum? •  How much does the antibiotic cost? Clinicians should be familiar with the general classes of antibiotics, their mechanisms of action, and their major toxicities. The differences between the specific antibiotics in …

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HIV / AIDS

Definition Table Centers for Disease Control and Prevention 1993 Revised Classification System for HIV Infection in Adults and AIDS Surveillance Case Definition and Table Centers for Disease Control and Prevention 1994 Revised Classification System for HIV Infection in Children Younger than 13 Years present the revised classification systems for adult and child HIV infection. Pathogenesis Transmission of HIV Infection with HIV occurs through three primary modes: sexual, parenteral, and perinatal. Sexual intercourse, primarily receptive anal and vaginal intercourse, is the most common vehicle for transmission. The probability of HIV transmission from receptive anorectal intercourse is 0.1% to 3% per sexual contact and 0.1% to 0.2% per sexual contact for receptive vaginal …

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Central Nervous System Infections

Definition Central nervous system infections include a wide variety of clinical conditions and etiologies: meningitis, meningoencephalitis, encephalitis, brain and meningeal abscesses, and shunt infections. The focus of this chapter is meningitis. Pathophysiology Infections are the result of hematogenous spread from a primary infection site, seeding from a parameningeal focus, reactivation from a latent site, trauma, or congenital defects in the central nervous system. central nervous system infections may be caused by a variety of bacteria, fungi, viruses, and parasites. The most common causes of bacterial meningitis include Streptococcus pneumoniae, Neisseria meningitides, Listeria monocytogenes, and Haemophilus influenzae. The critical first step in the acquisition of acute bacterial meningitis is nasopharyngeal colonization of …

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Antimicrobial Regimen Selection

Introduction A generally accepted systematic approach to the selection and evaluation of an antimicrobial regimen is shown in Table Systematic Approach for Selection of Antimicrobials. An «empiric» antimicrobial regimen is begun before the offending organism is identified, while a «definitive» regimen is instituted when the causative organism is known. Confirming the presence of infection Fever Fever is defined as a controlled elevation of body temperature above the normal range of 36.7 to 37.0В°C. Fever is a manifestation of many disease states other than infection. Many drugs have been identified as causes of fever. Drug-induced fever is defined as persistent fever in the absence of infection or other underlying condition. The fever …

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Infectious disorders

Infectious diseases comprise those illnesses that are caused by microorganisms or their products. Clinical manifestations of infection occur only when sufficient tissue injury has been inflicted directly by microbial products (e.g., endotoxins and exotoxins), or indirectly by host responses (e.g., cytokines and hydrolytic enzymes released by polymorphonuclear leukocytes). Despite the extraordinary recent advances that have occurred in therapeutics for infectious diseases, a number of basic principles should be followed to prescribe antimicrobials and vaccines is an optimal manner. This chapter addresses the broader issues of treating infectious diseases and provides a number of practical clinical examples to demonstrate rational therapeutics. A rational therapeutic strategy in the management of proved or suspected …

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