No,but Loudon County could be considered a DC suburb despite not touching the city.I don't have the first clue where Loudon County is but your post seemed to suggest that simply because it doesn't touch DC it cannot be considered a suburb.
Perhaps I should have done more investigating to see exactly why you posted that comment.
Loudoun County is two counties west of DC and was/is a really beautiful horse farm county. As the populations increased in the closer surrounding areas people started to find places to live that were further from people and traffic. Counties like Loudoun, and my county, Stafford (#20 on the list) started to get overrun with the liberal scum from the crowded areas near DC.
I was stationed in DC in 1992 and bought a home in Stafford because it was very rural, the county and school district didn't have any debt (they saved and paid cash for everything) and it was a place where a poor Air Force Captain could afford a home for his wife and two children. The median income was quite low.
Around 2000 all the liberals got tired of taxes and high costs of living and found counties like Stafford and Loudoun and started the infestation. We now have a huge population and the traffic is a nightmare all day long. My wife can retire in three years and we are gone.