Concatenate Input values in a Form along with the Title

Hey Guys,

Need a support.

I have a form on SharePoint that's required to be filled by the end users to get a Long Description (Check the Screen Shot below)

Now the next Task is to Concatenate the "Key Information" and "Input Values" for all the Non Blank  input values to create a Long Description.

Long Description Format Should look like:  

Where the Key Information and Input Values are concatenated using ":", and separated by  other Specification with a ",".

If you'll notice, the Specifications with Blank Values are not there in the above description.

I would really appreciate any support here.

Rgds,

Vikrant