Dear Dr. Roach: Our 18-year-old has been exposed to mono. Can you provide some information about this disease, including symptoms, treatment, complications and dangers of exposure to other family members, including toddlers and senior citizens? F.J.M.
ANSWER: Infectious mononucleosis symptoms can be caused by several viruses and one parasite (toxoplasmosis), but classically, it is caused by Epstein-Barr virus, of the herpes family. Its symptoms can be quite varied, and although for most people it is a self-limited illness, symptoms can be severe and long-lasting in some people, while others will have no apparent symptoms.
The cardinal symptoms (the major symptoms leading to recognition of the disease) in mononucleosis are fever; fatigue; a sore, inflamed throat; and enlarged lymph nodes. It is mostly shed by saliva, and infected people are often contagious for six months. Some people shed the virus after a natural infection for decades.
The fatigue is difficult to overstate. In some people, it can be profound, preventing exercise and studying abilities for a few weeks, up to six months. The sore throat and drainage can look like strep throat, and many people are mistakenly given amoxicillin or other antibiotics. This is a problem, because rash is common and not due to allergy to the antibiotic.
The spleen can get very enlarged, as can other lymph organs, especially the lymph nodes in the throat, which occasionally can swell enough to threaten the airway. Fortunately, a rupture of the spleen and acute airway closure are rare complications.
Neurologic complications can include Guillain-Barre syndrome and damage to individual nerves. Hepatitis is more common than most people realize, but it rarely causes serious problems. A host of other complications are possible but extremely rare.
Senior citizens are not likely to be at high risk: 90-95% of adults have evidence of immunity in the blood. Young infants and toddlers usually have very mild disease, sometimes unnoticed clinically. Immunocompromised people, like people with cancer or HIV, are at high risk from this disease.
Treatment usually is neither given nor effective for mononucleosis. There are a few exceptions: Airway obstruction and severe liver disease are treated with high-dose steroids. This is not used for most cases, as there are concerns about immunity and the possibility of worsening the risk of EBV-related malignancy, especially head and neck carcinomas.
