The patient is usually of school age (nursery through night
school) and complains of several days of fever, malaise, lassitude,
myalgias, and anorexia, culminating in a severe sore throat. The
physical examination is remarkable for generalized lymphadenopathy,
including the anterior and posterior cervical chains and huge tonsils,
perhaps meeting in the midline and covered with a dirty-looking
exudate. There may also be palatal petechiae and swelling, splenomegaly, hepatomegaly, and a diffuse maculopapular rash.
What to do:
Perform a complete physical examination, looking for signs of other
ailments, and the rare complication of airway obstruction, encephalitis,
hemolytic anemia, thrombocytopenic purpura, myocarditis, pericarditis,
hepatitis, and rupture of the spleen.
Send off blood tests: a differential white cell count (looking for
atypical lymphocytes) and a heterophil or monospot test. Either of these
tests, along with the generalized lymphadenopathy, confirms the
diagnosis of mononucleosis, but atypical lymphocytes are less specific,
being present in several viral infections.
Culture the throat. Patients with mononucleosis harbor group A
streptococcus and require penicillin with about the same frequency as
anyone else with a sore throat.
Warn the patient that the convalescence is longer than that of most
viral illnesses (typically 2-4 weeks, occasionally more), and that he
should seek attention in case of lightheadedness, abdominal or shoulder
pain,or any other sign of the rare complications above.
Despite controversy, prednisolone is widely employed for
symptomatic relief of infectious mononucleosis, usually 40mg of
Prednisone qd for five days. It is particularly helpful in young adults
with severe pharyngeal pain, odynophagia or marked tonsillar
enlargement with impending oropharyngeal obstruction.
Arrange for medical followup.
What not to do:
Do not routinely give penicillin for the pharyngitis, and certainly do
not give ampicillin. In a patient with mononucleosis, ampicillin can
produce an uncomfortable rash, which, incidentally, does not imply
allergy to ampicillin.
Do not unnecessarily frighten the patient about splenic rupture. If the
spleen is clinically enlarged, he should avoid contact sports, but
spontaneous ruptures are rare.
All of the above probably apply to cytomegalovirus as well,
although the severe tonsillitis and positive heterophil test are both less
likely. Some who report having mono twice probably actually had CMV
once and mono once.