Chickenpox laboratory findings: Difference between revisions
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Also, screening may be advised for newborns, pregnant women, prior to [[organ transplantation]], and in those with [[HIV AIDS|HIV/AIDS]]. | Also, screening may be advised for newborns, pregnant women, prior to [[organ transplantation]], and in those with [[HIV AIDS|HIV/AIDS]]. | ||
Testing may be used to | Testing may be used to determine if someone has been previously exposed to varicella zoster virus either through past infection or had received vaccination and has developed immunity to the disease. | ||
==Laboratory Findings== | ==Laboratory Findings== |
Revision as of 14:13, 23 June 2017
Chickenpox Microchapters |
Diagnosis |
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Treatment |
Case Studies |
Chickenpox laboratory findings On the Web |
American Roentgen Ray Society Images of Chickenpox laboratory findings |
Risk calculators and risk factors for Chickenpox laboratory findings |
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] Associate Editor(s)-in-Chief: Aravind Reddy Kothagadi M.B.B.S[2]
Overview
Diagnosis of Chickenpox is usually based upon signs and symptoms of the affected individual.
Laboratory tests are not routinely used to diagnose active cases of chickenpox and shingles, which are caused by the varicella zoster virus (VZV).
Children are nowadays vaccinated and most adults generally may have been infected with VZV in their early years.Hence, general population screening is not done usually. Anyhow, testing for VZV or for the antibodies produced in response to VZV infection may be performed in when required for screening purposes.
Also, screening may be advised for newborns, pregnant women, prior to organ transplantation, and in those with HIV/AIDS.
Testing may be used to determine if someone has been previously exposed to varicella zoster virus either through past infection or had received vaccination and has developed immunity to the disease.
Laboratory Findings
- Laboratory tests can help confirm the diagnosis, if needed. They are:
- Antibody Testing
- Viral detection
- VZV DNA testing
- Direct Fluorescent Antibody (DFA)
- VZV culture
Antibody Testing
- When an individual is exposed to VZV, their immune system responds by producing antibodies to the virus. Laboratory tests detect and measure the level of two classes of VZV antibodies in the blood namely IgM and IgG.
IgM
- First antibodies to be produced in response to the infection.
- Can be detected within a week or two post exposure.
- The levels of IgM antibodies rises for a short period of time and then falls below detectable levels.
- Post-Infection, in the future, the IgM levels rise only when the latent VZV is reactivated.
IgG
- Produced several weeks after the initial exposure.
- IgG levels rise during active infection and then the levels become stable as the VZV infection gets resolves and as the virus gets inactivated.
- Provides Long-Term protection
Viral detection
- Viral detection is done by finding VZV in a blood, vesicle fluid, or tissue sample. Detection done by culturing the virus or by detecting it's genetic material (VZV DNA).
VZV DNA testing
- Performed to detect VZV genetic material in a person's sample. This method is sensitive. It can identify and measure the amount of the virus.
Direct Fluorescent Antibody (DFA)
- DFA test visualizes the presence of VZV in the cells taken from an individuals's skin lesion using a special microscope and labeled antibody. Advantages of DFA test are that it is rapid, but less specific and sensitive than DNA testing.
VZV culture
- Culture is not very reliable for VZV and can lead to false-negative results.
The choice of tests and samples collected depends on the person, their symptoms, and on the healthcare practitioner's clinical findings.
Microscopic Findings
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Photomicrograph reveals the intranuclear inclusions produced by varicella virus grown in a tissue culture (500x mag). From Public Health Image Library (PHIL). [1]
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Cytoarchitectural histopathologic changes which you’d find in a human skin tissue specimen that included a chickenpox (125x mag). From Public Health Image Library (PHIL). [1]
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Hematoxylin-eosin (H&E)-stained photomicrograph reveals some of the cytoarchitectural histopathologic changes which you’d find in a human skin tissue specimen that included a chickenpox, or varicella zoster virus lesion (125x mag). From Public Health Image Library (PHIL). [1]
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Photomicrograph reveals some of the cytoarchitectural histopathologic changes which you’d find in a human skin tissue specimen that included a chickenpox, or varicella zoster virus lesion (500x mag). From Public Health Image Library (PHIL). [1]
-
Hematoxylin-eosin (H&E)-stained photomicrograph reveals some of the cytoarchitectural histopathologic changes which you’d find in a human skin tissue specimen that included a chickenpox, or varicella zoster virus lesion (50x mag). From Public Health Image Library (PHIL). [1]
-
Hematoxylin-eosin (H&E)-stained photomicrograph reveals some of the cytoarchitectural histopathologic changes which you’d find in a human skin tissue specimen that included a chickenpox, or varicella zoster virus lesion (50x mag). From Public Health Image Library (PHIL). [1]
-
Photomicrograph reveals some of the cytoarchitectural histopathologic changes which you’d find in a human skin tissue specimen that included a chickenpox, or varicella zoster virus lesion (500x mag). From Public Health Image Library (PHIL). [1]
-
Photomicrograph reveals some of the cytoarchitectural histopathologic changes which you’d find in a human skin tissue specimen that included a chickenpox, or varicella zoster virus lesion (1200x mag). From Public Health Image Library (PHIL). [1]
-
Photomicrograph reveals some of the cytoarchitectural histopathologic changes which you’d find in a human skin tissue specimen that included a chickenpox, or varicella zoster virus lesion (1200x mag). From Public Health Image Library (PHIL). [1]