Parvo B19 infection Flashcards
most common clinical presentation for Parvo B19
asymptomatic or have flu like symptoms
clinical presentation of Parvo B19
erythema infectiosum (fifth’s disease): fever, nausea, slapped cheek rash in kids
acute, symmetric, arthralgia, arthritis: hands, wrists, knees and feet (resembles RA)
transient pure red cell aplasia, aplastic crisis with pts who have underlying hematological disease (sickle cell)
diagnosis of Parvo B19 infection:
B19 IgM antibodies in immunocompetent pts
NAAT for B19 DNA in immunocompromised pts
Previous infection B19 antibodies (documents immunity)
reactivation of prior infection (NAAT for B19 DNA)
what is NAAT?
B19 nucleic acid amplification testing
Parvo B19 virus incubation period
flu like symptoms 5-10 days after exposure
who gets particularly bad course with Parvo B 19 infection?
sickle cell pts. can have a transient aplastic crisis
immunocompromised pts develop acute or chronic anemia due to bone marrow suppression of erythroid precursors.
how to avoid the pitfall of picking RA when the pt has Parvo B19
Pt may have positive RF but if symptoms are <6 weeks in duration don’t pick RA.
Same joint distribution but instead check IgM for Parvo B19
when does Parvo B19 arthritis resolve?
it is self limiting and will resolve in 1-2 months . Treatment is supportive and monitoring. no effective vaccine for Parvo B19.
do we ever check Parvo B19 IgG antibodies for acute infection?
no because 50% will have positive IgG antibodies; only reflect past exposure.
acute rheumatic fever presentation?
fever and migratory arthritis of the large joints (knees) or elbows or ankles. But also has to have other major JONES criteria: Joints, pancarditis, subcutaneous nodules, erythema marginatum and Syndeham chorea.
Late complication of Strep pyogenes (strep A) pharyngitis.
