Infectious mononucleosis Monocytic angina Dr hab. n. med. Ewa Majda-Stanisławska

EBV is associated with the development of malignancies Burkitt's lymphoma, lymphoproliferative disease, Hodgkin's lymphoma, primary central nervous system (CNS) lymphomas in AIDS, nasopharyngeal carcinoma based on seroepidemiologic data and the detection of EBV genomes in these tumors.

Seroprevalence Antibodies are acquired earlier in life in developing than in industrialized countries, By adulthood 90% to 95% of most populations have demonstrable EBV antibodies, In USA and in GB, EBV seroconversion occurs before the age of 5 years in about 50% of the population. , A second wave of seroconversion occurs midway through the second decade of life.

Methods of Spread Low titer of EBV is present in throat washings of infected patients The virus persists in the B-cell compartment for the life of the infected host It can be cultured from: throat washings from 10% to 20% of normal healthy adults, from 50% of kidney transplant recipients, from greater proportions of those critically ill with leukemia or lymphoma

Methods of Spread EBV is a widespread agent that is not particularly contagious Most cases of infectious mononucleosis are probably contracted by intimate contact between susceptible individuals and asymptomatic shedders of EBV Among young adults, spread of the virus may be facilitated by the transfer of saliva with kissing.

Clinical characteristics sore throat, fever, lymphadenopathy serologically by the transient appearance of heterophile antibodies hematologically by a mononuclear leukocytosis that consists, in part, of atypical lymphocytes

The age of the patient has a profound influence on the clinical expression of EBV infection In children, primary EBV infection is often asymptomatic. Young children may be more likely to exhibit rashes, neutropenia, or pneumonia Clinically apparent infections in very young children are heterophile negative in about one half of the cases.

Incubation period of acute infectious mononucleosis is 30 to 50 days

General patient’s complaints The onset may be abrupt, But usually there are several days of prodromal symptoms : chills, sweats, feverish sensations, anorexia, malaise, loss of taste for cigarettes is common, retro-orbital headaches, myalgias, feelings of abdominal fullness sore throat, which may be the most severe the patient has experienced.

Signs - fever Fever is present in more than 90% The fever usually peaks in the afternoon with temperatures of 38° C to 39° C, In most cases, fever resolves over a 10- to 14-day period

Signs - rash A rash, which may be macular, petechial, scarlatiniform, urticarial, or erythema multiforme-like, is present in about 5% of patients. The administration of ampicillin or amoxicillin produces a pruritic, maculopapular eruption in 90% to 100% of the patients The ampicillin-related rash does not necessarily predict future intolerance to ampicillin or amoxicillin

Periorbital edema has been reported in up to one third of cases in some series, but it has been observed less frequently in others.

Signs - pharyngitis Tonsillar enlargement is usually present, Occasionally tonsils are meeting at the midline. The pharynx is erythematous with an exudate in about one third of cases Palatal petechiae may be seen in 25% to 60% of cases The petechiae are usually multiple, 1 to 2 mm in diameter, occur in crops lasting 3 to 4 days, and are usually seen at the junction of the hard and soft palate

Signs - lymphadenopathy Cervical adenopathy, usually symmetrical, is present in 80% to 90% of patients, Posterior adenopathy is most common, Submandibular and anterior adenopathies are quite frequent as well, Axillary and inguinal adenopathies also occur, Individual nodes are freely movable, are not spontaneously painful, and are only mildly tender to palpation

Signs - hepatosplenomegaly Abdominal examination may detect hepatomegaly in 10% to 15% of cases, Jaundice is present in approximately 5% of cases. Splenomegaly is present in about one half of cases if sought carefully over the course of the illness. The splenomegaly is usually maximal at the beginning of the second week of illness and regresses over the next 7 to 10 days.

Complications Autoimmune hemolytic anemia occurs in 0.5% to 3% Most patients with infectious mononucleosis recover uneventfully Complications are rare, and mostly reversable Autoimmune hemolytic anemia occurs in 0.5% to 3% Mild thrombocytopenia Splenic rupture is a rare but dramatic neurologic: encephalitis , cerebellitis

Laboratory diagnosis The central hematologic manifestation of the illness is a circulating lymphocytosis. Relative and absolute mononuclear lymphocytosis is found in about 70% of the cases. The lymphocytosis peaks during the second or third week of illness, monocytes and lymphocytes account for 60% to 70% WBC the total white cell counts of 12,000 to 18,000/mm3. Higher white cell counts are not uncommon, occasional patients manifest 30,000 to 50,000 leukocytes/mm3. Atypical lymphocytes are the hematologic hallmark of infectious mononucleosis and account for about 30% of the differential count at their zenith

Other diseases occuring with atypical lymphocytes CMV infection, Primary HIV, Viral hepatitis, Toxoplasmosis, Rubella, Mumps, Roseola Drug reactions

Latex agglutination test Monotest Detects heterophile antibodies, originally described by Paul and Bunnell as sheep erythrocyte agglutinins, They are present in about 90% of the cases at some point during the illness

Other Laboratory Abnormalities Liver function test results are abnormal in almost all cases of infectious mononucleosis. Aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase are elevated, usually of mild degree The alkaline phosphatase level is elevated in about 60% of the cases. Mild elevation of the bilirubin level is noted in approximately 45%

TREATMENT Largely supportive because more than 95% of the patients recover uneventfully without specific therapy. The level of activity is generally tailored to what the individual patient can tolerate comfortably. To avoid trauma to the spleen, contact sports or heavy lifting should be avoided during the first month of illness and until any splenomegaly has resolved. Acetaminophen or nonsteroidal anti-inflammatory agents can be helpful in relieving the sore throat and in suppressing the fever. Sore throat may be further alleviated by gargling with warm salt water.

Treatment Corticosteroids should not generally be used in uncomplicated infectious mononucleosis They decrease the period of febrility and hasten the resolution of tonsillopharyngeal symptoms May be helpful in cases of: Tonsillar enlargement causing airway compromise Autoimmune hemolytic anemia, Severe thrombocytopenia, Aplastic anemia. CNS involvement