Questions for Doper Doctors about mono

A friend of mine (actually a friend, and not me) has mononucleiosis. What exactly is this? I know it’s a viral infection, but of what? Lymphatics? Is it confined to the oral cavity? What about other mucus membranes? Is it only spread through coughing, kissing, sharing eating utilsils, etc?

She has obviously been told to rest and avoid exercise. The only reason her doctor gave her for this is that her spleen might rupture. How common is a ruptured spleen anyway? Is that the only indication for rest or are there other complications seen with exercise?

Feel free to be as thorough as you’d like to be, I don’t particularly need layman’s terms.


Mono is a self-limited febrile illness associated with the Epstein-Barr virus, characterized by malaise, stomatitis, pharyngitis, generalized lymphadenopathy (esp. cervical, ie neck), enlarged spleen, and abnormal white blood cells. It is encountered mostly in the young, but its actual prevalance is doubtless underestimated, since symptoms may be quite mild and go unreported.

Its manifestations vary greatly from person to person, , but generallly begin with vague malaise, chills, mild fever and sore throat, which last 3 to 6 days. By week 2 or 3, the illness often progresses to increased fever (up to 103 is common), with debilitating sore throat, and prominent swelling of the lymph nodes, especially under the jaw. Half of examined patients have enlarged spleens (the spleen being filled with lymphocytes), and somewhat less than half also get an enlarged liver. up to 10% may have actual hepatitis with jaundice due to the virus. A fine rash, similar to rubella may occur, and so can conjunctivitis, or inflammation of the inner eyelids.

In less that one percent of the cases, the central nervous system becomes involved, and one may see stupor, headache, palsies and seizures, all resulting from a virus-induced meningoencephalitis or polyneurits.

fatalities are infrequent, and are usually associated with splenic rupture from trauma. (I’ve seen 3 cases of splenic rupture from kids with mono playing High School football, 1 died). Occasionally the throat swells so much as to cut off the airway, but this is extremely rare. Also rare is liver failure due to the virus, and fatal seizures, or fatal hemorrhage due to reduced platelets.

Transmission is from blood and oral secretions. Its classically been called the “kissing disease” but more often a transmission is associated with sharing eating utensils or glasses.

Complete recovery is the expected outcome, with the illness usually running its course in 3 to 5 weeks. Chronic fatigue can be a problem for months afterward. Some individuals suffer prolonged symptoms, or distant relapses.

Mono is often initially misdiagnosed as a strep throat. This is usually due to the fact that the serologic tests for mono don’t turn positive until the 2nd or 3rd week of the infection. Likewise, the abnormal white blood cells don’t appear until later in the course.

Therapy is supportive. No good anti-viral meds have yet been found for the infection. Occasionally steroids are used to reduce the throat swelling. Ampicillin and Amoxicillin are to be especially avoided, not only because they do no good (it’s a virus, dammit), but also because they tend to cause a rash more frequently in the patient with mono. Fluids, pain and fever relievers, topical anesthetics like throat lozenges are the rule. And no contact sports for at least a month!

That’s probably more than you wanted to know. There’s lots of current controversy about exactly what the infectious virus does, and how it can be combatted, and what other related illnesses it may cause or contribute to, but that’s a whole 'nother note.

That is exactly what I wanted, thank you.

Are contact sports to be avoided so that there isn’t trauma to the spleen or because of the fatigue associated with the virus? My friend is also a diver (like in the olympics, not scuba) and that’s not usually considered a contact sport, although there could be some trauma if she did a belly flop.

splenic trauma is to be avoided, this includes pressure changes, even those found in a clean dive. Going 10 feet under causes as much pressure on the abdomen as a mild to moderate blow to the stomach. It doesn’t feel the same as being slugged in the guy because the pressure is applied equally all over, but it could still result in dire consequences.