Q: I am positive for Parvovirus B19 IgG. Normal range is <0.9 and mine is 6.3. All
other AI subtests are wnl except for ANA of 1:640. I have no symptoms of this
virus other than a random flare of arthritis. I've researched a bit on line and
this virus seems to be prevalent in some RA studies of which RA like symptoms
can also be linked to SjS, of which I do have symptoms. Please advise your
opinion on this blood test. Is it a significant finding in AI diseases?
A: Parvovirus is one of the several viruses that has been linked to autoimmunity, especially Rheumatoid Arthritis(RA). Parvovirus can trigger RA, especially in a genetically susceptible host (HLA DR4 phenotype). Parvo can also cause an arthritis by itself which is self limited-resolving in 6-12 months.
The Parvovirus IgM is negative and the IgG is positive means there was exposure to this virus at one time.. Most of us have had contact with the virus in the past; such a test has no clinical significance. However, a positive ANA at a titer of 1:640 (? pattern) is usually clinically significant, especially if there are symptoms (arthritis, dryness). ANA and arthritis favor SLE and or Sjs (if the RF and CCP Ab are negative). There is another test-Parvovirus PCR- that can indicate ongoing viral activity, if this would help your clinician sort through things.