I guess it is an outcome of these things being names based on symptoms rather than causes.
Just look at cancer, depending on where it originates it can have a multitude of causes. But MSM is likely to report every new finding as just cancer, with zero details about the type involved.
Just look at cancer, depending on where it originates it can have a multitude of causes. But MSM is likely to report every new finding as just cancer, with zero details about the type involved.