Well, I haven't used Lightroom specifically yet, but being an Adobe product, there are a couple of things I would check.
First and foremost, if it was working right before and isn't now, I'd check your profiles and make sure nothing got changed by accident or something. I don't know how much you know about this stuff, but in a small nutshell, each device you use (camera, monitor, printer, etc.,) has to have a color profile to interpret the colors you see on the screen vs. what's printed, etc.. Essentially, a "255 pure red" may look one way to your camera, another way to your monitor and yet another way to your printer. Ideally, all your hardware should use the same profile...sRGB for example.
What I would do here is, if as you say the images are printing correctly from Elements and not Lightroom, compair the color profiles and see if they're using the same profiles. This should be under either your color settings or preferences somewhere. If you're printing these on your own printer, I would also compare this under your print properties as well...make sure that both programs are using the same printer profiles too. NOTE: Do be aware that "sRGB IEC61966-2.1" and "Adobe RGB (1998)" are two different color sets! 9 out of 10 times when you're having a problem with color consistancy, something with the profiles are to blame.
Now I would also like to add that it's also possible that perhaps one of your profile files has become corrupt. Which leads me to my second suggestion. If the profiles you're using appear to be correct, you may simply need to completely uninstall and then reinstall Lightroom. This is important...if you have to re-install, make sure you completely uninstall the program first! Get the whole freakin thing off your harddrive before you reinstall it.
Lastly, I have to ask something here too....when you say that your printing your photos, do you mean on your own printer or at a lab? If you're doing this on your own printer, then please disregard this comment. However if your having these printed at a photo place then it's possible that they may have done something with their software. I had this happen with Ritz camera...every time they upgraded their kiosk software, they changed their color profiles and the colors would go REALLY wonkey on my pictures...bright green kangaroo's for example. Unfortunately, the people at Ritz really didn't have a clue what they were doing either...their so-call lab technician didn't even know what a color profile was! LOL!!! The two places I use now for my prints use the standard sRGB profile mentioned above, so it's the same one I use on my system here at home.
Alrighty, good luck and I hope this helps!