Diarrhea is it sign of leukemia?

Not usually: Leukemia symptoms are typically fever, pain, weight loss, night sweats, lymph node swelling, unusual bruising, and/or abnormal bleeding. Isolated diarrhea is more likely to be infection

Can it be seen ..: Yes but it's by no means a defining symptoms. Diarrhea can be caused by numerous different reasons ... but cancer is rarely the first thing to come to mind. Is there a reason why you're thinking of leukemia? You don't give much history beyond a fever, which combined with diarrhea is more commonly associated with an infectious form of diarrhea. Hopefully this can give you some reassurance.

No : Diarrhea ( without blood) is not a specific sign of leukemia.