Question

A 5-year-old child is brought with fever, fatigue, and left ventricular dysfunction. An endomyocardial biopsy is shown below. What is the probable diagnosis?

• A. Acute rheumatic fever
• B. Chagas disease
• C. Pyogenic myocarditis
• D. Lymphocytic myocarditis

Answer 1

The Correct Option is D

Lymphocytic myocarditis is the correct diagnosis for the presented case of a 5-year-old child with symptoms of fever, fatigue, and left ventricular dysfunction. This condition is characterized by the presence of inflammatory infiltrates predominantly composed of lymphocytes within the myocardium.

The clinical presentation of myocarditis can vary but typically includes signs of heart failure such as dyspnea, fatigue, and in severe cases, chest discomfort or arrhythmias. The endomyocardial biopsy is a critical tool for the definitive diagnosis of myocarditis. In lymphocytic myocarditis, the biopsy would usually show:

• An inflammatory infiltrate mainly composed of lymphocytes.
• Myocyte necrosis or damage without significant neutrophilic infiltrates (which would suggest bacterial infection).

This differentiates lymphocytic myocarditis from other types, such as:

• Acute rheumatic fever: Typically associated with Aschoff bodies and pancarditis, involves all layers of the heart.
• Chagas disease: Caused by Trypanosoma cruzi, characterized in chronic phases by myocardial fibrosis and often mega-syndromes.
• Pyogenic myocarditis: Indicates bacterial infection and would show a neutrophilic infiltrate.

Given these distinctions and the biopsy findings, lymphocytic myocarditis is the most probable diagnosis.