Антитела к вирусу Варицелла-Зостер (VZV, IgG)

Varicella-zoster virus (VZV) IgG antibody testing assesses immune status to the agent of chickenpox and shingles. The assay helps determine whether an individual has evidence of prior infection or vaccination and, therefore, likely protection against varicella. The test may also support evaluation of suspected varicella or herpes zoster when the presentation is unusual or the diagnosis cannot be made confidently on clinical grounds. Synonyms commonly used include VZV IgG and anti-VZV IgG.

Varicella-zoster virus causes two distinct clinical syndromes: primary infection results in varicella (chickenpox), and reactivation from latency produces herpes zoster (shingles). Most cases are diagnosed clinically; serology is useful when findings are atypical or when immune status must be documented. IgG testing is not the primary tool for acute diagnosis but can complement other assays. Determining VZV IgG is particularly relevant before pregnancy because varicella during gestation can lead to maternal and fetal complications. Varicella usually occurs in childhood, although adults tend to experience more severe illness. Transmission is typically airborne from contact with an infected individual. The incubation period is about 2 weeks (10 to 21 days). Early manifestations include fever and malaise, followed 1–2 days later by a generalized vesicular rash. Lesions crust and resolve over approximately 2 weeks, usually without scarring. After recovery, lifelong immunity develops. During pregnancy, varicella poses hazards: disease severity is greater in the mother, and pneumonia occurs in about 20 % of cases. Fetal risks include cutaneous scarring, limb hypoplasia, microcephaly, encephalitis, and ocular injury. Maternal infection near delivery can cause severe neonatal varicella with a risk of death. After primary infection, VZV remains latent in neurons and may reactivate with stress, immunosuppression, or abrupt cooling, often in older adults. Herpes zoster typically begins with malaise and fever, followed by localized pain or dysesthesia on the trunk or, less commonly, the face. A unilateral dermatomal vesicular eruption appears 1–3 days after pain onset. Neuralgia may persist for about a month after the rash resolves. Unlike chickenpox, shingles is not considered hazardous during pregnancy. Humoral responses include multiple immunoglobulin classes. IgM appears earlier, whereas IgG develops later but persists for life in VZV infection. Consequently, VZV IgG is an unreliable marker of acute disease because it remains detectable indefinitely after prior infection. In very early varicella, IgG can be negative because it may take several weeks to appear. For preconception screening, however, VZV IgG reliably establishes whether immunity is present.