Turnaround time is defined as the usual number of days from the date of pickup of a specimen for testing to when the result is released to the ordering provider. In some cases, additional time should be allowed for additional confirmatory or additional reflex tests. Testing schedules may vary.
Red-top tube or gel-barrier tube
Hemolysis; lipemia; gross bacterial contamination
Diagnose VZV infection; determine adult susceptibility to infection
Chemiluminescent immunoassay (CLIA)
• Equivocal: 135−165 index
• Positive: >165 index
Although most cases of varicella or zoster are clinically unambiguous, serology may be occasionally useful in the differential diagnosis of other blistering illnesses or when infection shows an unusual complication, such as hepatitis. It may also be important to establish whether an individual is susceptible when clinical history is unclear, or when varicella immune globulin may be needed, as in the immunocompromised host or cancer patient on toxic chemotherapy. Zoster is more common with aging and may occur in the face of significant antibody titers, demonstrating that cell-mediated immunity is also significant.