Dermatomal herpes zoster and chickenpox are generally diagnosed empirically on the basis of the clinical appearance of characteristic
lesions. Laboratory studies may be required for confirmation Selleck NVP-BKM120 in atypical cutaneous presentation. The diagnostic procedure of choice was formerly the detection of virus antigens expressed on the surface of infected cells obtained directly from cutaneous lesions. Cells were stained with specific fluorescein-conjugated monoclonal antibodies to confirm the presence of VZV antigens. This technique is rapid, and reliable. In the diagnosis of VZV infection, virus culture is less sensitive than direct antigen staining with reported sensitivity of 49% as compared to 97.5% [18]; however, virus culture in a patient with suspected aciclovir-resistant VZV infection would allow for the identification
of aciclovir resistance [14]. PCR based diagnosis is more rapid and more sensitive than culture based Selleck Tigecycline diagnosis in immunocompetent populations, demonstrating a sensitivity of 100% vs. 29% for culture with a specificity of 100% in one study and has replaced direct antigen staining in many centres [19,20]. There is much less evidence for the performance of these tests in HIV-seropositive groups specifically. Findings in the CSF of a pleocytosis, mildly raised protein and positive PCR for VZV DNA are supportive of the diagnosis
of herpes zoster CNS disease [21,22]. The absence of a positive PCR for VZV DNA in the CSF does not exclude a diagnosis of zoster CNS disease [22]. In series including HIV seropositive and seronegative individuals with compatible clinical disorders the VZV PCR had an 80% sensitivity and 98% specificity for the diagnosis of neurological VZV infection [23]. However interpretation of the PCR result must take into Progesterone account the full clinical details [22] since at least in immunocompetent individuals transient viral reactivation of unclear significance has been described [24]. Histopathology and PCR for VZV DNA can be helpful in the diagnosis of visceral disease. 6.2.6.1 Varicella. Treatment of primary varicella in HIV-seropositive patients should begin as early as possible. There is limited data from studies in HIV-seropositive individuals on which to base recommendations and as pointed out in other published guidelines extrapolation of data from other immunocompromised groups is required [25]. Treatment with intravenous aciclovir (5–10 mg/kg every 8 h) for 7–10 days is advised [26], though more prolonged treatment courses may be required until all lesions have healed.