Pediatric Primary Care (57 page)

2.  Clinical symptoms result from proliferation of b-lymphocytes in the epithelial cells of the pharynx, parotid duct, lymph nodes, spleen.

3.  Spread primarily in saliva.

4.  Latent, lifelong infection occurs and may be reactivated during immunosuppression.

B.  Occurrence.

1.  Humans.

a.  Endemic worldwide in younger children, especially third world countries.

b.  One-third of cases in adolescents in more affluent populations of developed countries.

c.  Almost all adults in United States are seropositive for EBV.

C.  Clinical manifestations.

1.  Primary EBV infection.

a.  Incubation is 30-50 days.

b.  Primary EBV infection in adolescents presents in > 50% of cases with:

•  Fatigue, malaise, myalgia.

•  Generalized lymphadenopathy.

•  Pharyngitis.

•  Possibly fever or prodrome of malaise and fever.

c.  Younger children may experience mild febrile episode, rash, abdominal pain.

D.  Physical findings.

1.  Tonsillitis, pharyngitis: possibly exudative.

2.  Palatal petechiae (transient).

3.  Lymphadenopathy.

a.  Anterior and posterior cervical nodes, also axillary or inguinal nodes.

b.  Large, mildly tender.

c.  Epitrochlear nodes highly indicative.

4.  Splenomegaly.

a.  Frequent false negatives, if done too early in 50% of cases.

b.  2-3 cm below costal margin.

c.  Persists for 2-4 weeks past resolution of other symptoms.

E.  Diagnostic tests.

1.  “Monospot” (mononucleosis rapid slide agglutination test for heterophile antibodies disease process) 25% false negative in the first week of the disease. In children younger than 12 years of age monospot detects 25-50% of cases.

2.  CBC with differential.

a.  Lymphocytosis with up to 20,000 WBCs.

b.  Up to 40% atypical lymphocytes.
Note:
50% lymphocytes with 10-20% atypical lymphocytes diagnostic.

c.  Mild thrombocytopenia 50% of cases.

d.  Positive monocytes on differential.

3.  Liver enzymes.

a.  Mild hepatitis common.

b.  Usually asymptomatic.

4.  EBV serology: indicated in acutely ill patient.

a.  If monospot negative and strong suspicion.

b.  VCA-IgM test if monospot negative and urgent diagnosis needed such as in a competitive athlete.

5.  Throat culture.

a.  Rule out other causes.

b.  5-25% cases have concurrent GABHS infection.

F.  Differential diagnosis.

1.  Other causes of infectious mononucleosis-like syndrome (in descending order of incidence):

a.  Cytomegalovirus.

b.  Toxoplasmosis gondii.

c.  HIV-mucocutaneous lesions, diarrhea, nausea and vomiting, weight loss.

d.  Human herpesvirus.

e.  Rubella.

2.  Pharyngitis/tonsillitis.

a.  GABHS–absence of hepatosplenomegaly; fatigue less prominent.

b.  Other bacterial causes.

c.  Viruses other than EBV.

3.  Leukemias.

4.  Infectious mononucleosis should be suspected in any febrile patient with sore throat plus palatal petechiae, splenomegaly, posterior cervical, and possibly axillary or inguinal adenopathy.

G.  Treatment.

1.  Supportive.

a.  Analgesics and antipyretics.

b.  Hydration support if needed.

c.  Corticosteroids may be indicated if:

•  Impending airway obstruction or dehydration secondary to severe tonsillopharyngitis.

•  Massive splenomegaly.

•  Myocarditis.

•  Hemolytic anemia.

•  Hemophagocytic syndrome.

H.  Follow up.

1.  Fatigue may persist months after recovery. Patient should be allowed to resume school and activities as energy level permits.

2.  Splenomegaly.

a.  Risk of rupture is estimated at 0.1% (50% are spontaneous).

b.  Recheck at weekly intervals.

c.  Avoid contact sports at least 3-4 weeks until fully recovered and spleen no longer palpable.

d.  Consider selective ultrasonography such as when an athlete would like to return to competitive sports in < 4 weeks.

I.  Complications.

1.  Additional complications are rare, but include:

a.  Dehydration.

b.  Antibiotic-induced rash (most commonly when ampicillin or amoxicillin antibiotic used for concurrent bacterial infection).

c.  Thrombocytopenia.

d.  Airway obstruction.

e.  Acute interstitial nephritis.

f.  Hemolytic anemia.

g.  Myocarditis.

h.  Neurologic abnormalities.

i.  Cranial nerve palsies.

j.  Encephalitis.

k.  Retrobulbar neuritis.

J.  Education.

1.  Close personal contact is required for transmission.

2.  Recovery often biphasic, with worsening of symptoms after period of improvement.

3.  Full recovery may take months.

4.  Patient should not donate blood.

VIII. PHARYNGITIS

A.  Etiology.

1.  Inflammation of mucous membranes and underlying structures of pharynx and tonsils, usually caused by infection.

2.  Causative agents.

a.  Respiratory viruses, including rhinovirus, adenovirus, coxsackievirus, Epstein-Barr virus.

b.  GABHS.

c.  Group C beta-hemolytic strep (not a cause of rheumatic fever), Neisseria gonorrhoeae rarely.