Infectious mononucleosis: Difference between revisions
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==Background==
==Background==
*Caused by Epstein-Barr virus
*Caused by Epstein-Barr virus
**CMV and HHV-6 may cause mononucleosis-like illnesses
**[[CMV]] and [[HHV-6]] may cause mononucleosis-like illnesses
*Infects B lymphocytes which causes dissemination
**T lymphocytes fight infection
**In patients with decreased T cell function, can lead to continued proliferation and [[lymphoma|neoplastic transformation]]


==Clinical Features==
==Clinical Features==
[[File:2549px-Lymphadanopathy.jpg|thumb|Neck lymphadenopathy associated with infectious mononucleosis.]]
[[File:Mononucleosis.jpg|thumb|Exudative pharyngitis in a person with infectious mononucleosis.]]
[[File:Cross Reaction Rash.jpg|thumb|Rash from using penicillin while infected with mono.]]
*Triad of:
*Triad of:
**Fever
**[[Fever]]
**Pharyngitis
**[[Pharyngitis]]
**Lymphadenopathy
**[[Lymphadenopathy]]
*Symptoms
*Symptoms
**abrupt or insidious, ha, fever & malaise common w/ st & lad to follow
**Abrupt or insidious
**[[Rash]] in 10-15% usu btwn 4th-6th day of illness
**[[Headache]], [[fever]], and malaise common, [[sore throat]] and lymphadenopathy follow
***red macular or maculopapular morbilliform rash of trunk & upper arms
**[[Rash]] in 10-15% usually between 4th-6th day of illness
***occ involves face, thigh & legs, periorbital & eyelid edema in 50% of cases
***Red macular or maculopapular morbilliform [[rash]] of trunk & upper arms
 
***Occasionally involves face, thigh and legs, periorbital & eyelid edema in 50% of cases
==Diagnosis==
***Most often mono is diagnosed based on other signs <ref>Sara Bode; Contagious Exanthematous Diseases. ''Quick References 2022''; 10.1542/aap.ppcqr.396150</ref>
*Heterophile antibody (monospot) test
*Previously treated as [[strep pharyngitis]]
**Up to 25% of pts in 1st week of symptoms may have false negative test
**Morbilliform [[rash]] can develop<ref>Luzuriaga K and Sullivan JL. Infectious mononucleosis. N Engl J Med. 2010; 362:1993-2000.</ref>
**10% of pts w/ EBV infection will be persistently negative
***95% of patients on [[amoxicillin]] or [[ampicillin]]
*Amoxicillin reaction
***40-60% with other beta-lactams
**Amoxicillin in pt w/ EBV will cause maculopapular rash in most
*Illness typically 2-4 weeks, but malaise and fatigue may last for months
*Definitive testing for suspected Mono during pregnancy (to r/o other pathology)
**Send for: Epstein Barr virus, cytomegalovirus, and HIV


==Differential Diagnosis==
==Differential Diagnosis==
*[[Hepatitis]]
{{Throat pain DDX}}
{{Throat pain DDX}}


===Pediatric Rashes===
{{Peds Rash DDX}}
{{Peds Rash DDX}}


==Treatment==
==Evaluation==
[[File:SplenomegalyandsubcaphematomaMarked.png|thumb|Splenomegaly due to mononucleosis resulting in a subcapsular hematoma]]
===Work-up===
*Heterophile antibody (monospot) test vs EBV IgM Assay
*CBC
**Lymphocytosis (≥50% lymphocytes)
***10% or more atypical lymphocytes
***Hypersegmented neutrophils
**[[Thrombocytopenia]]
*[[LFTs]]
**Elevations in AST and ALT is expected up to 5x
*Suspected mononucleosis during pregnancy (also need to rule out other pathology):
**[[Epstein-Barr virus]], [[cytomegalovirus]], and [[HIV]]
 
===Diagnosis===
*Heterophile antibody (monospot) test
**Sensitivity of 87% and specificity of 91% <ref>Sylvester JE, Buchanan BK, Silva TW. Infectious Mononucleosis: Rapid Evidence Review. Am Fam Physician. 2023 Jan;107(1):71-78. PMID: 36689975.</ref>
**Up to 25% of patients in 1st week of symptoms may have false negative test<ref>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.</ref>
**10% of adult patients with EBV infection will be persistently negative
**Up to 50% of pediatric patients will be persistently negative<ref>Papesch M and Watkins R. Epstein-Barr virus infectious mononucleosis. Clin Otolaryngol Allied Sci. 2001; 26(1):3-8.</ref>
*EBV IgM Assay
**Carries 97% sensitivity and 94% specificity at symptom onset<ref>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.</ref>
 
==Management==
*Supportive
*Supportive
*Avoid contact sports for 1-2 months<ref>O'Connor TE, Skinner LJ, Kiely P, Fenton JE. Return to contact sports following infectious mononucleosis: the role of serial ultrasonography. Ear Nose Throat J. 2011 Aug;90(8):E21-4.</ref> (decrease risk of splenic rupture)
==Disposition==
*Discharge
==References==
<references/>


==Source==
Tintinalli


[[Category:ID]]
[[Category:ID]]
[[Category:Peds]]
[[Category:Pediatrics]]

Latest revision as of 21:31, 4 March 2023

Background

  • Caused by Epstein-Barr virus
    • CMV and HHV-6 may cause mononucleosis-like illnesses
  • Infects B lymphocytes which causes dissemination
    • T lymphocytes fight infection
    • In patients with decreased T cell function, can lead to continued proliferation and neoplastic transformation

Clinical Features

Neck lymphadenopathy associated with infectious mononucleosis.
Exudative pharyngitis in a person with infectious mononucleosis.
Rash from using penicillin while infected with mono.
  • Triad of:
  • Symptoms
    • Abrupt or insidious
    • Headache, fever, and malaise common, sore throat and lymphadenopathy follow
    • Rash in 10-15% usually between 4th-6th day of illness
      • Red macular or maculopapular morbilliform rash of trunk & upper arms
      • Occasionally involves face, thigh and legs, periorbital & eyelid edema in 50% of cases
      • Most often mono is diagnosed based on other signs [1]
  • Previously treated as strep pharyngitis
  • Illness typically 2-4 weeks, but malaise and fatigue may last for months

Differential Diagnosis

Acute Sore Throat

Bacterial infections

Viral infections

Noninfectious

Other

Pediatric Rash

Evaluation

Splenomegaly due to mononucleosis resulting in a subcapsular hematoma

Work-up

  • Heterophile antibody (monospot) test vs EBV IgM Assay
  • CBC
    • Lymphocytosis (≥50% lymphocytes)
      • 10% or more atypical lymphocytes
      • Hypersegmented neutrophils
    • Thrombocytopenia
  • LFTs
    • Elevations in AST and ALT is expected up to 5x
  • Suspected mononucleosis during pregnancy (also need to rule out other pathology):

Diagnosis

  • Heterophile antibody (monospot) test
    • Sensitivity of 87% and specificity of 91% [4]
    • Up to 25% of patients in 1st week of symptoms may have false negative test[5]
    • 10% of adult patients with EBV infection will be persistently negative
    • Up to 50% of pediatric patients will be persistently negative[6]
  • EBV IgM Assay
    • Carries 97% sensitivity and 94% specificity at symptom onset[7]

Management

  • Supportive
  • Avoid contact sports for 1-2 months[8] (decrease risk of splenic rupture)

Disposition

  • Discharge

References

  1. ↑ Sara Bode; Contagious Exanthematous Diseases. Quick References 2022; 10.1542/aap.ppcqr.396150
  2. ↑ Luzuriaga K and Sullivan JL. Infectious mononucleosis. N Engl J Med. 2010; 362:1993-2000.
  3. ↑ Melio, Frantz, and Laurel Berge. “Upper Respiratory Tract Infection.” In Rosen’s Emergency Medicine., 8th ed. Vol. 1, n.d.
  4. ↑ Sylvester JE, Buchanan BK, Silva TW. Infectious Mononucleosis: Rapid Evidence Review. Am Fam Physician. 2023 Jan;107(1):71-78. PMID: 36689975.
  5. ↑ 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.
  6. ↑ Papesch M and Watkins R. Epstein-Barr virus infectious mononucleosis. Clin Otolaryngol Allied Sci. 2001; 26(1):3-8.
  7. ↑ 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.
  8. ↑ O'Connor TE, Skinner LJ, Kiely P, Fenton JE. Return to contact sports following infectious mononucleosis: the role of serial ultrasonography. Ear Nose Throat J. 2011 Aug;90(8):E21-4.
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