Infectious mononucleosis

Revision as of 14:41, 26 August 2015 by Neil.m.young (talk | contribs) (ebv igm added)

Background

  • Caused by Epstein-Barr virus
    • CMV and HHV-6 may cause mononucleosis-like illnesses

Clinical Features

  • Triad of:
    • Fever
    • Pharyngitis
    • Lymphadenopathy
  • Symptoms
    • abrupt or insidious, ha, fever & malaise common w/ st & lad to follow
    • Rash in 10-15% usu btwn 4th-6th day of illness
      • red macular or maculopapular morbilliform rash of trunk & upper arms
      • occ involves face, thigh & legs, periorbital & eyelid edema in 50% of cases
  • Previously treated at strep throat
    • Morbilliform rash can develop[1]
      • 95% of patients on amoxicillin or ampicillin
      • 40-60% with other beta-lactams

Differential Diagnosis

Acute Sore Throat

Bacterial infections

Viral infections

Noninfectious

Other

Pediatric Rash

Diagnosis

Work-up

  • Heterophile antibody (monospot) test
    • Up to 25% of pts in 1st week of symptoms may have false negative test[3]
    • 10% of adult pts w/ EBV infection will be persistently negative
    • Up to 50% of pediatric pts will be persistently negative[4]
  • EBV IgM Assay
    • Carries 97% sensitivity and 94% specificity at symptom onset[5]

Evaluation

  • Clinical features in conjunction with positive monospot.
  • Amoxicillin reaction is helpful in diagnosis
    • Amoxicillin in pt w/ EBV will cause maculopapular rash in most
  • Suspected mononucleosis during pregnancy (also need to r/o other pathology):
    • Epstein Barr Virus, Cytomegalovirus, and HIV

Management

  • Supportive
  • Avoid contact sports

Disposition

  • Discharge

References

  1. Luzuriaga K and Sullivan JL. Infectious mononucleosis. N Engl J Med. 2010; 362:1993-2000.
  2. Melio, Frantz, and Laurel Berge. “Upper Respiratory Tract Infection.” In Rosen’s Emergency Medicine., 8th ed. Vol. 1, n.d.
  3. Pitetti RD, Laus, S, and Wadowsky, RM. Clinical evaluation of a quantitative real time polymerase chain reaction assay for diagnosis of primary Epstein-Barr virus infection in children. Pediatr Infect Dis J. 2003; 22:736–739.
  4. Papesch M and Watkins R. Epstein-Barr virus infectious mononucleosis. Clin Otolaryngol Allied Sci. 2001; 26(1):3-8.
  5. Bruu, AL, et al. Evaluation of 12 commercial tests for detection of Epstein-Barr virus-specific and heterophile antibodies. Clin Diagn Lab Immunol. 2000; 7:451–456.