LG Nexus 5 is not detected despite having installed LG Universal Mobile Drivers
I found the issue. I tried installing some other generic LG drivers which were interfering with the other drivers. (LGUnitedMobileDriver_S498MA22_WHQL_ML_Ver_2.2)

To solve this:


I uninstalled the generic LG drivers (LGUnitedMobileDriver_S498MA22_WHQL_ML_Ver_2.2) like a software (Control Panel -> Uninstall or Change a Program)
Turn on the USB Debugging
Unplug and replug the device
In the Windows Device Manager the MTP was shown with an exclamation mark
Open it and ask Windows to find a driver automatically which it did successfully. You will need an Internet connection
Should work now