My 2 mos. old daughter has diarrhea for 12 days now and she's loosing weight too. wbc is 15.40 and there's no parasite found in her stool.

More tests: Diarrhea usually goes away on its own within 48 hours without medication. Persistent diarrhea for 2 weeks is considered chronic. The elevated white count is indicative of a bacterial infection. If one stool culture was negative, it should be repeated. Maybe it's time to consult a GI or infectious disease specialist to investigate all possibilities.