Pediatric Mononucleosis and Epstein-Barr Virus Infection Clinical Presentation

Updated: Mar 22, 2021
  • Author: Jaya Sureshbabu, MBBS, MRCPCH(UK), MRCPI(Paeds), MRCPS(Glasg), DCH(Glasg); Chief Editor: Russell W Steele, MD  more...
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Infectious mononucleosis most often begins insidiously, with vague malaise, followed several days later by fever, fatigue, sore throat, and swollen posterior cervical lymph nodes. The prodrome period may last 1-2 weeks. Some patients experience an abrupt influenza-like onset, with fever, chills, body aches, retro-orbital headache, and sore throat.

The incubation period in adolescents is 4-7 weeks (32-48 days); however, it is shorter in young children, with a median duration of illness of 16 days, and the mean duration of 19 days, longer than other usual viral illnesses. [1, 6, 46]



Physical Examination

Sore throat, fatigue, headache, fever, body aches, decreased appetite, and abdominal discomfort are common symptoms.

Pharyngitis, tonsillar exudate, generalized lymphadenopathy, hepatosplenomegaly, eye lid edema, facial puffiness, maculopapular rash, and rarely jaundice are the frequent signs in EBV infection.

Sore throat is the most frequent presenting symptom, and occasionally pharyngitis is seen without sore throat. Many patients describe sore throat as the "worst" they have ever had. Pharyngitis is usually accompanied by marked tonsillar enlargement, occasionally with exudates. Another frequent feature is the presence of petechiae at the junction of the hard and soft palate. Because the pharyngitis resembles streptococcal infection, when ampicillin or amoxicillin is prescribed, virtually all patients develop an erythematous maculopapular rash ("ampicillin rash"). Otherwise 3-15% of patients develop a maculopapular rash, probably owing to immune-mediated vasculitis, and it resolves without specific treatment. In infants and  children, EBV infection is associated with Gianotti-Crosti syndrome, characterized by a symmetric rash on cheeks, extremities, and buttocks with multiple erythematous papules, which may coalesce into plaques and may persist for 15-50 days.

Fatigue and cervical adenopathy involving anterior and posterior nodes are seen in 90-95% of patients. Submandibular nodes and less commonly axillary and inguinal nodes are also enlarged. Epitrochlear lymphadenopathy is particularly suggestive of infectious mononucleosis if present.

Acute upper abdominal pain is present in about 30% patients owing to hepatitis, and left upper quadrant pain may be due to splenic enlargement. Hepatitis, documented by abnormal liver function tests, is seen in 80% of cases, and it should be considered as part of the acute disease rather than a complication. Liver involvement is subclinical in 90-95% of patients, but the remainder develop jaundice, and a few of them complain of tenderness in the right upper quadrant of the abdomen that is likely due to hepatic swelling with pressure on the liver capsule.

The spleen is often palpable 2-3 cm below the left costal margin and may be tender. The spleen rapidly enlarges over the first week of symptoms, usually decreasing in size over the next 7-10 days. The spleen can rupture from relatively minor trauma or even spontaneously. Acute severe abdominal pain should prompt suspicion of splenic rupture.

Flu-like symptoms such as headache, body ache, and chills are also common in young adults.

Eyelid edema, which gives the patient a slit-eyed appearance and may be accompanied by facial puffiness, is seen in 10% of patients. It is another symptom that is unusual in other viral illnesses and is a useful clinical clue in EBV infection (Hoagland sign).

Symptoms usually persist for 2-3 weeks, but fatigue is often more prolonged.

Infants and young children with primary infection are usually asymptomatic. Children younger than 4 years frequently have splenomegaly or hepatomegaly, rash, and nonspecific symptoms of an upper respiratory tract infection.