Ver el código de «Infectious mononucleosis»

==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 [[lymphoma|neoplastic transformation]]

==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:
**[[Fever]]
**[[Pharyngitis]]
**[[Lymphadenopathy]]
*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 <ref>Sara Bode; Contagious Exanthematous Diseases. ''Quick References 2022''; 10.1542/aap.ppcqr.396150</ref>
*Previously treated as [[strep pharyngitis]]
**Morbilliform [[rash]] can develop<ref>Luzuriaga K and Sullivan JL. Infectious mononucleosis. N Engl J Med. 2010; 362:1993-2000.</ref>
***95% of patients on [[amoxicillin]] or [[ampicillin]]
***40-60% with other beta-lactams
*Illness typically 2-4 weeks, but malaise and fatigue may last for months

==Differential Diagnosis==
{{Throat pain DDX}}

{{Peds Rash DDX}}

==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
*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/>


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