if some one is suffering from constipation or digestion problem and a clear liquid discharge from anus is it najis ?

getting this details online about disease
Another possible reason could be anal fistula, a very small tract that develops due to some kind of infection. When the fistula gets infected, it may drain liquid. This usually doesn’t hurt but may itch and cause discomfort by irritating surrounding skin. 

Does the clear liquid contain blood or feces?