Histopathological an D Immunohistochemica L Stud Y of Th E Brai N an D Hear T I N Th E Chroni C Cardia C Form

A h i s t o p a t h o l o g i c a l a n d i m m u n o h i s t o c h e m i c a l s t u d y of t h e b r a i n a n d h e a r t w a s m a d e in 50 p a t i e n t s w i t h t h e c h r o n i c c a r d i a c f o r m of C h a g a s ' d i s ease . T h e i m m u n o h i s tochemica l t e c h n i q u e u s e d w a s t h e p e r o x i d a s e a n t i p e r o x i d a s e m e t h o d a d a p t e d for t h e d e m o n s t r a t i o n of t h e T. c ruz i a m a s t i g o t e s . H i s t o l o g i c a l a n d i m m u n o h i s t o c h e m i c a l e x a m i n a t i o n of t he b r a i n s h o w e d e n c e p h a l i t i s in m u l t i p l e foci, a l t h o u g h s p a r s e , in four p a t i e n t s ( 8 % ) . I n one of t h e p a t i e n t s t h e p r o c e s s w a s r ecen t , ac t ive , a n d c o n t a i n i n g p a r a s i t e s . I n t h e o t h e r t h r e e p a t i e n t s , t h e les ions w e r e of m i n o r i n t e n s i t y , w i t h l i g h t e x u d a t i v e i n f l a m m a t o r y c h a n ges , s u g g e s t i n g a p r o c e s s b e c o m i n g inac t ive , o r a l r e a d y inac t ive . T h e s e a r c h for p a r a s i t e s in t h e s e t h r e e p a t i e n t s w a s n e g a t i v e , even w i t h u s e of i m m u n o p e r o x i d a s e . T h e h e a r t h i s tological a n d i m m u n o h i s t o c h e m i c a l s t u d y showed , b e s i d e s t h e c h r o n i c m y o c a r d i t i s in m u l t ip le foci a s s o c i a t e d w i t h i n t e r s t i t i a l f ib ros i s , a m a s t i g o t e s in seven p a t i e n t s (14%). T h e absence of p a r a s i t e s a n d of i n f l a m m a t o r y c h a n g e s in t h e b r a i n in t h e g r e a t m a j o r i t y of p a t i e n t s w i t h c h r o n i c C h a g a s ' d i s ea se , c o n t r a s t i n g w i t h t h e c o n s t a n t f i n d i n g of i n f l a m m a t o r y c h a n g e s a n d t h e occas iona l f i n d i n g of a m a s t i g o t e s in t h e m y o c a r d i u m of t h e s a m e p a t i e n t s , a l lows u s t o s t a t e , i n t h e s a m e w a y o t h e r a u t h o r s d id , t h a t t h e r e is n o h i s t opa tho log i ca l b a s i s to s u p p o r t t h e e x i s t e n c e of t h e c h r o n i c n e r v o u s fo rm of C h a g a s ' d i sease .