Infectious Mononucleosis (IM) Liu Quanbo, associate professorDIVISION OF INFECTIOUS DISEASE OF CHONGQING MEDICAL DIVISION OF INFECTIOUS DISEASE OF CHONGQING MEDICAL UNIVERSITYUNIVERSITY IntroductionoInfectious mononucleosis(IM) is an infectious disease caused by Epstein-Barr virus(EBV) .oThe clinical features include fever, pharyngitis , and generalized lymphadenopathy.oThe characteristics of lab study is atypical lymphocytosis in the peripheral blood.Etiology Epstein-Barr virus(EBV) 1. Classification：ndouble-stranded DNA virus n-Family: Herpesviridaen-Subfamily: -herpesvirinae2. Characteristics of EBVnLatent-reactivenLymphotropic virus just infecting B-LCncapacity to have B lymphocyte proliferate infinitely (immortalization ) Epstein-Barr virus(EBV) Etiology3、Viral Antigen Systemsnviral capsid antigen, VCAnEB nuclear antigen, EBNAnearly antigen, EAnlymphocyte-detected membrane antigen, LYDMAnmembrane antigen, MA Epidemiology1. Infectious sources Patients, persons with latent infection and carriers2. Routes of transmission ：nContact transmission through the mouth (exchange of saliva) nblood transmission occasionally 3. Population susceptibilitynSchool age children and adolescents 4. Epidemiological featuresnPeak seasonsnEpidemiological statusPathogenesisEBV salivary glands infects oral epithelial cells and B-LC in pharynx pharyngitispharyngitisLymphadenopathyLymphadenopathy in cervical nodes in cervical nodesexcrete EBV Continuously or intermittently B-LC in the peripheral blood and the entire lymphoreticular system viremia Activation of polyclonal B-LC polyclonal antibodiesSpecific Absheterophil AbautoantibodyTc responsed to the infected B-LCEffect on B-LC containing EBVatypical LCHepatosplenomegaly, lymphadenectasis, myocarditis, pneumonia, etc.Changes of antigenicity on the surface of B-LC Specific Abs PathologyoThe basic pathological change is the benign lymphadenosis oThe main damage is in monocyte-macrophage system nLymph nodes：non-pyogenic lymphadenectasis with LC and monocyte-macrophage system proliferationnSpleen: lots of atypical LCnLC infiltration and limited necrotic lesions in organs such as liver, heart, kidney, lung, CNS,etc.ManifestationsThe incubation period ：515 days1. fever2. pharyngitis: 80%. sore throat, tonsillar enlargement, nhyperemia , edema and exudates（50%）3. generalized lymphadenopathy： 80100%. nThe most common lymphadenopathy is enlargement of cervical lymph nodes4. splenohepatomegalia:nhepatomegaly： 3050%. Among them, 2/3 has elevated liver enzymes Jaundice is uncommon. Liver failure may occurred in few cases.nsplenomegaly：5070%5. rashes： 10%6. others：stuff nose, snore, edema of the eyelids, etc The tonsils are hyperemic and edematous covered with gray-white exudates. ManifestationsThe incubation period ：515 days1. fever2. pharyngitis: 80%. sore throat, tonsillar enlargement, nhyperemia, edema and exudates（50%）3. generalized lymphadenopathy： 80100%. nThe most common lymphadenopathy is enlargement of cervical lymph nodes4. splenohepatomegalia:nhepatomegaly： 3050%. Among them, 2/3 has elevated liver enzymes Jaundice is uncommon. Liver failure may occurred in few cases.nsplenomegaly：5070%5. rashes： 10%6. others：stuff nose, snore, edema of the eyelids, etc cervical lymph nodescervical lymph nodes ManifestationsThe incubation period ：515 days1. fever2. pharyngitis: 80%. sore throat, tonsillar enlargement, nhyperemia , edema and exudates（50%）3. generalized lymphadenopathy： 80100%. nThe most common lymphadenopathy is enlargement of cervical lymph nodes4. splenohepatomegalia:nhepatomegaly： 3050%. Among them, 2/3 has elevated liver enzymes Jaundice is uncommon. Liver failure may occurred in few cases.nsplenomegaly：5070%5. rashes： 10%6. others：stuff nose, snore, edema of the eyelids, etc 临床表现Complicationsnnerve system：encephalitis,Guillain-Barr syndrome, Reye syndrome, Peripheral neuritis, etc.ncardiovascular system：Myocarditis, pericarditis nhematological system：Hemolytic anemia, Aplastic anemia, thrombocytopenia, neutropenia, hemophagocytic syndrome, etc.nrespiratory system：upper airway obstruction, interstitial pneumonia, etc.nurinary system：nephritis, nephrotic syndrome, etc.ndigestive system：gastrointestinal bleeding, liver failure, etc.nsubcapsular splenic hemorrhage or splenic rupture Lab studies1. blood routine ：nthere is leukocytosis of 1020109/L, of which at least are lymphocytes; n109/L absolutely notice:2. detection of markers of EBVnheterophil agglutination test oprincipleolimitationsndetection of EBV Abs: VCA IgM3. detection of nucleic acid of EBV by PCR4. Isolation of EBV atypical lymphocytesDiagnosis1. IM triadnFever, pharyngitis and enlargement of cervical lymph nodes2. 109/L absolutely 3. heterophil agglutination test or/and VCA IgM (+)Differential Diagnosis 1. suppurative tonsillitis 2. infectious mononucleosis-like syndrom 3. viral hepatitis 4. Kawasaki disease 5. malignant histocytosisTreatment1. general treatment2. symptomatic treatment3. antiviral therapy4. the use of glucocorticoid：n indicatorPrognosis