Endomyocardial fibrosis and eosinophilia

Area of Science:

• Cardiology
• Tropical Medicine
• Immunology

Background:

• Endomyocardial fibrosis (EMF) is a tropical heart disease with unclear etiology.
• Eosinophilia and parasitic infections are prevalent in tropical regions, raising questions about their role in EMF.

Purpose of the Study:

• To investigate the relationship between absolute eosinophil counts, parasitic infections, and endomyocardial fibrosis in African patients.
• To differentiate African EMF from other eosinophilic cardiac conditions.

Main Methods:

• Assessed absolute eosinophil counts in 15 African patients with endomyocardial fibrosis.
• Reviewed literature on potential etiological factors including genetic, environmental, and immunological aspects.

Main Results:

• Mean eosinophil counts were higher in EMF patients than reported normals, but the absolute range was comparable.
• A high prevalence of parasitic infections (malaria, hookworm, strongyloides) was observed, but correlation with eosinophilia was poor.
• African EMF appears distinct from Löffler's endocarditis and other eosinophilic cardiac conditions.

Conclusions:

• Parasitic infections and eosinophilia are common in the tropics but do not appear to be the primary drivers of African endomyocardial fibrosis.
• Genetic, environmental, and immunological factors are likely crucial in the causation of endomyocardial fibrosis in Uganda.