Mononucleosis, Infectious

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Mononucleosis, Infectious

DRG Category:866
Mean LOS:3.4 days
Description:MEDICAL: Viral Illness Without Major CC

The term mononucleosis refers to the presence of an abnormally high number of mononuclear leukocytes (white blood cells [WBCs]) in the body. Infectious mononucleosis (IM) results from a viral syndrome caused by the Epstein-Barr virus (EBV). The virus is introduced into the host by close contact with another individual who is shedding EBV in the oropharynx. The virus replicates in epithelial cells of the pharynx and salivary glands. A localized inflammatory response produces the pharyngeal exudate. The virus is then carried via the lymphatics to the lymph nodes. Local and generalized lymphadenopathy (disease of the lymph nodes) develops.

Major complications are rare but may include splenic or liver rupture, aseptic meningitis or encephalitis, pericarditis, or hemolytic anemia. EBV has been linked to Burkitt’s lymphoma in Africa and to nasopharyngeal carcinoma, particularly in Asians. Mononucleosis can also lead to Guillain-Barré syndrome.


Infection with EBV, a herpes virus, is common throughout the world in humans. EBV is probably spread via the oropharyngeal or respiratory route. EBV is also transmitted by blood transfusion.

Genetic considerations

There is an X-linked disorder (X-linked lymphoproliferative disease) that confers high susceptibility to EBV infection, which is caused by mutations in the SH2 domain protein-1A (SH2D1A) gene. An autosomal recessive susceptibility to EBV infection has also been reported.

Gender, ethnic/racial, and life span considerations

IM rarely occurs in children under age 5. EBV infection occurs early in life, however, among individuals of lower socioeconomic groups and in developing countries, which protects them from IM. IM is most often diagnosed in adolescents who come from higher socioeconomic groups and in college students. The peak incidence of IM is ages 16 to 18 in boys and 14 to 16 in girls. Approximately 12% to 30% of the total cases of IM occur among university students and military cadets. By adulthood, most individuals have had at least one infection with EBV. There are no known ethnic or racial considerations. There are no known gender considerations, but more than 90% of associated splenic ruptures are found in males.

Global health considerations

Globally, a large proportion of the population are exposed to EBV during childhood and adolescence. Precise data on global prevalence of mononucleosis are unknown. In developing regions of the world, approximately 90% of children have an EBV infection (but not IM) before age 5.



The patient often reveals contact with a person who has had IM. Although children have a short incubation period of about 10 days, symptoms in adults may not appear until 1 to 2 months after exposure to the EBV. The patient with suspected IM typically reports a history of fever and fatigue for 1 week, followed by a sore throat (often described as the most painful the patient has ever experienced). Other symptoms include anorexia, painful swallowing, and swelling of the lymph nodes.

Physical examination

Common symptoms include fever, sore throat, and swollen lymph nodes. Note the redness of the pharynx and observe for exudate. Observe for petechiae that may appear at the junction of the hard and soft palates (occurs in 25% of patients). Note any facial edema, particularly eyelid edema. Facial edema is rarely encountered in other illnesses of young adults and is suggestive of IM. Some patients have a maculopapular rash (discolored patches of skin mixed with elevated red pimples). Palpate for enlarged lymph nodes in the cervical and epitrochlear (around the elbow) areas. Significant adenopathy is almost always present, and its absence should make one doubt the diagnosis of IM. During an abdominal examination, palpate for an enlarged spleen (occurring in 50% of patients) and liver. Use care during the examination and perform a gentle examination.


The patient with IM has a viral illness that may last up to 4 weeks. Because most cases occur in college students, IM may prevent the student from performing academically at pre-illness levels. If the student falls behind in her or his studies, the student or parents may feel anxious or stressed. Assess the patient’s ability to cope with the interference with school tasks. Determine if the patient has discussed the illness with her or his professors and if arrangements have been made to make up work or withdraw from school if needed. If the young adult is employed rather than in school, determine if the patient has told the employer of her or his healthcare needs.

Diagnostic highlights

TestNormal ResultAbnormality With ConditionExplanation
Heterophile testTiter < 40Titer ≥ 40Heterophile antibody is an immunoglobulin M (IgM) antibody produced by infected B lymphocytes
MonospotNegativePresence of heterophil antibodiesIdentifies 90% of adult cases with EBV; most common and specific test to confirm diagnosis
Complete blood count with differentialRed blood cells: 4–5.5 million/μL; WBCs: 4,500–11,000/μL; hemoglobin: 12–18 g/dL; hematocrit: 37%–54%; reticulocyte count: 0.5%–2.5% of total RBCs; platelets: 150,000–400,000/μL; segmented neutrophils: 54%–62%; band neutrophils: 3%–5%; eosinophils: 1%–3%; basophils: < 1%; monocytes: 3%–7%; lymphocytes: 25%–33%Lymphocytosis with characteristic atypical lymphocytes in peripheral bloodDetermines extent of viral infection and immune dysfunction
IgM antibodiesNegativePresence of specific antibodies for EBV antigens (viral capsid antigens, early antigens, or Epstein-Barr nuclear antigen)Identifies presence of EBV

Primary nursing diagnosis


Risk for ineffective airway clearance related to oropharyngeal swelling


Respiratory status: Gas exchange and ventilation; Safety status: Physical injury; Comfort level


Airway insertion; Airway management; Airway suctioning; Oral health promotion; Respiratory monitoring; Ventilation assistance; Surveillance; Pain management; Analgesic administration; Anxiety reduction

Planning and implementation


Most patients require nothing more than supportive therapy, such as acetaminophen for fever and bedrest for fatigue. Pain relief is essential if the patient is to maintain fluid intake to prevent fluid volume deficit and dehydration.

To prevent upper airway obstruction from severe tonsillar enlargement, treatment with corticosteroids (prednisone 40 mg/day for 5 to 7 days) is sometimes indicated. If the patient is at risk for airway obstruction (a rare complication), endotracheal intubation may be necessary. About 20% of patients also need a 10-day course of antibiotic therapy because of streptococcal pharyngotonsillitis. Ruptured spleen is an unusual but serious complication that causes sudden abdominal pain and is managed surgically by removal of the spleen.

Pharmacologic highlights

No specific pharmacologic therapy treats mononucleosis; antiviral medications do not limit the EBV infection. Patients usually require analgesia with acetaminophen, propoxyphene (Darvon), or even oral narcotics. Some patients may also be placed on corticosteroids or antibiotics for complications such as inflammation, allergy, or infection.


Most patients do not require hospitalization for IM. Focus on supportive care and teaching. Encourage the patient to use anesthetic lozenges or warm saline gargles for pharyngitis. A soft diet such as milkshakes, sherbets, soups, and puddings provides additional liquid and nutritional supplements. Rest is critically important. Teach patients to avoid strenuous activities and contact sports until liver and spleen enlargement subsides.

Evidence-Based Practice and Health Policy

Macsween, K.F., Higgins, C.D., McAulay, K.A., Williams, H., Harrison, N., Swerdlow, A.J., & Crawford, D.H. (2010). Infectious mononucleosis in university students in the United Kingdom: Evaluation of the clinical features and consequences of the disease. Clinical Infectious Diseases, 50(5), 699–706.

  • A study among university students, which included 57 cases of infectious mononucleosis and 58 age- and gender-matched control cases, revealed increased experiences of fatigue among women when compared to men (p = 0.003). Women reported a median fatigue duration of 194 days compared to men who reported a median of 80 days (p = 0.03).
  • Sore throat was the most common presenting symptom (reported by 77% of patients), followed by fatigue (reported by 65% of patients) and lymphadenopathy (reported by 54% of patients and evident in 88% of patients upon physical examination). Seventeen percent of patients with infectious mononucleosis had splenomegaly, and 22% had hepatomegaly.
  • Seventy-five percent of patients with infectious mononucleosis reported missing a median of 11 hours of scheduled classes (range, 0 to 300 hours); however, women were more likely than men to discontinue their studies (16% versus 0%; p = 0.056).

Documentation guidelines

  • Physical findings of pharyngitis, lymphadenopathy, splenomegaly, fever, fatigue
  • Reaction to activity and immobility
  • Plan to deal with prolonged confinement and possible suspension of activities

Discharge and home healthcare guidelines

Teach the patient to prevent splenic rupture by avoiding minor trauma, heavy lifting, overexertion, and contact sports for 1 to 2 months. Teach strategies to avoid constipation and straining because these problems cause increased pressure on the spleen. Suggest over-the-counter medications for comfort. Encourage the patient to rest during the acute illness and convalescence period. Note that prolonged fatigue is not uncommon. Encourage students to notify professors about the illness and to arrange for less demanding assignments during the recovery period. Recommend that the patient plan for a recovery period of several weeks before resuming regular activities, academics, or employment.

Instruct the patient to promptly report to the physician any abdominal and upper quadrant pain radiating to the shoulder. In addition, if the patient reports shortness of breath or inability to swallow, he or she should call 911 for emergency help because tracheostomy or intubation may become necessary.

Diseases and Disorders, © 2011 Farlex and Partners

Patient discussion about Mononucleosis, Infectious

Q. What is the connection between fibromyalgia and glandular fever? How can you protect yourself from this viral infection?

A. There is a notion that some of the autoimmune conditions are caused by a trigger in the shape of a virus. Like the papiloma virus and cervical cancer. So there might be a connection between fibromyalgia and a virus.

Q. can mono kill you if it gets to the liver? otherwise known as the kissing desiaes.

A. It can be fatal, not necessarily through infecting the liver but through rupture of enlarged spleen or obstruction of the throat, or through the development of cancer (e.g. lymphoma) later in life.

However, these complications are very rare, and most people recover from the disease without major complications.

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