Myocarditis Etiology

Myocarditis Etiology

Viral – Coxsackie A, ECHO, Influenza, Entero,

HIV, Adeno, CMV

Chlamydia and Rickettsia

Bacteria – diphtheria, Neisseria, Borrelia

Protozoa – Trypanosoma, Toxoplasma, Trichinella

Hypersensitivity – SLE( Libman Sacks endocarditis), RHD, graft rejection

Drugs: doxorubicin

Physical Agents – Radiation

Idiopathic – Giant cell myocarditis

Myocarditis Morphology

Gross –dilated, flabby heart, pale patches with hemorrhage giving mottled appearance, abscess if bacterial

Microscopic – interstitial inflammatory infiltrate with myocyte necrosis, fibrosis, viral inclusion bodies

Mononuclear cells – idiopathic or viral

Neutrophils – bacterial

Eosinophils –hypersensitivity or protozoa

Granulomatous – TB or sarcoid

Dilated, globoid

heart in

myocarditis

Bacterial colony in myocarditis

Toxoplasmosis

Chagas disease