My grandma has had severe diarrhea vomiting fever headache for over a month. She was told she had a water born parasite even though they did not find that in her blood test. They gave her 2 rounds of antibiotics and now she is worse. She was hospitalized for 3 days and they did a blood and stool test. They could not find anything and again blamed it on a parasite and sent her home. When she was in the hospital her blood pressure also dropped. She is still nauseous and has severe diarrhea. She has also recently developed a cough. She is 75 years old and I feel that they need to do more extensive testing....Should we demand certain test to be done?