parvovirus B19

Introduction

parvovirus B19, human

Pathology

• arthritis
  • virus may be present in synovial tissue cells by PCR
• hypoplastic anemia & pancytopenia may occur in adults
  • infects erythrocyte precursors (giant, abnormal proerythroblasts)
  • transient aplasia, reversing spontaneously in a week or two
  • generally becomes apparent only in individuals with underlying chronic hemolytic anemia (sickle cell anemia), dependent upon increased erythrocyte production
• erythema infectiousum in children
• hydrops fetalis
• generally does not harm fetus
  • can cause fetal anemia, cardiac failure, hydrops fetalis
    • risk greatest 9-20 weeks of gestation & 2-4 weeks after maternal infection

Clinical manifestations

• nonspecific, flulike symptoms may precede rash
  • fever, myalgia, headache
• facial rash
  • erythematous malar rash (slapped-cheek rash, erythema infectiousum)
  • facial rash often followed by a generalized reticular or maculopapular rash
    • faint maculopapular rash on chest & arms
    • case with no facial rash
• systemic symptoms have usually resolved with appearance of generalized maculpapular rash
• rheumatoid arthritis-like syndrome in adults
  • acute symmetric inflammatory polyarthritis
  • rash may be absent in adults
  • hands, wrists & knees most commonly affected
    • small joints of the hands most often affected
      • MCP joints affected
  • median duration is 10 days; however a few cases may last for years

Laboratory

• parvovirus B19 IgM
  • test in pregnant woman 2-4 weeks after maternal infection
• PCR/RT-PCR for parvovirus B19
  • parvovirus B19 DNA
  • parvovirus B19 RNA
• see ARUP consult

Complications

• pure red cell aplasia
  • direct antiglobulin test (DAT) would rule out pure red cell aplasia (even in patients with CLL known for positive DAT in some patients)

• disease interaction(s) of parvovirus B19 with hemolytic anemia

Differential diagnosis

• disseminated gonorrhea
  • no flu-like syndrome of headache, fever, myalgia preceding rash
    • symptoms of fever, chills & malaise may precede migratory arthritis & rash by a week or two
  • asymmetric arthritis, oligoarthritis or monoarthritis favors gonorrhea
  • a positive history of sexual activity increases likelihood of gonorrhea
  • purulent conjunctivitis not a feature of parvovirus B19
  • migratory arthritis not a feature of parvovirus B19

Management

• NSAID for symptomatic treatment
• intravenous immunoglobulin

More general terms

• parvovirus