Acquired Megacolon Complicated by Massive Rectal Intussusception and Volvulus of the Sigmoid: Case Report

AS FAR as we h a v e b e e n a b l e to d e t e r m i n e , n o o t h e r i n s t a n c e h a s b e e n r e p o r t e d of mas s ive r ec t a l p r o l a p s e c a u s e d by i n t u s s u s c e p t i o n of o n e p o r t i o n of the s i g m o i d f l exure , c o m p l i c a t e d by v o l v u l u s of an o t h e r p o r t i o n of t he s a m e s e g m e n t of b o w e l . A n a b n o r m a l l y l o n g s i g m o i d f l e x n r e is neces sa ry for d e v e l o p m e n t of b o t h of these c o n d i t i o n s in t h e s a m e s e g m e n t of the c o l o n . B o t h c o n d i t i o n s , i t w o u l d seem, a re a m e n a b l e to t h e s a m e type of s u r g i c a l o p e r a t i o n . O n l y t h e t ype of p r o l a p s e a s s o c i a t e d w i t h s i g m o i d a l i n t u s s u s c e p t ' o n w i l l be cons id e r e d in t h i s r e p o r t . V o l v u l u s of t he s i g m o i d f l exu r e is a re la t ive ly r a r e cause of o b s t r u c t i o n of t h e l a r g e bowe l , a c c o u n t i n g p e r h a p s fo r 2.0 p e r c e n t of a l l o b s t r u c t i o n s of t h e i n t e s t i n e a n d 20 p e r c e n t of a l l i n t e s t i n a l to r s ions . 2 I t m a y p r o g r e s s r a p i d l y a n d b e c o m e c o m p l i c a t e d b y ea r ly g a n g r e n o u s c h a n g e s of the b o w e l w a l l o r i t m a y r u n a p r o t r a c t e d c o u r s e of s e v e n to t en clays of a l m o s t c o m p l e t e c o l o n i c obs t r u c t i o n w i t h s t r a n g u l a t i o n o c c u r r i n g as a r e l a t i v e l y l a t e c o m p l i c a t i o n . A u t h o r i t i e s c l a i m t h a t n e a r l y 50 p e r c e n t of t h e cases of s i g m o i d a l v o l v u l u s o c c u r in m e n t a l l y d e f i c i e n t p a t i e n t s . T h e case p r e s e n t e d h e r e w i t h possesses m a n y of t h e s a l i e n t f e a t u r e s of t he i n t u s s u s c e p t i n g t ype 0,5 : 'ectal p r o l a p s e a n d o~ t h e s u b a c u t e f o r m of v o l v u l u s of t he s i g m o i d f l exure .