You could also replace <br/>
with 

and add a linefeed-treatment="preserve"
attribute to your <fo:block>
.
Something like:
<fo:block linefeed-treatment="preserve">This is an example Description.
List item 1
List item 2
List item 3
List item 4</fo:block>
Edit
Some users may need to use \n
instead of 

depending on how they are creating the XML. See Retain the 
 during xml marshalling for more details.