<s>[INST] my 33 year old sister was having horrible diarreha about 1 month ago.  She went to the Dr. at which time they ran test and found that she had Giardia and was also anemic.  They gave her medication for the parasite.  During that time, they also found liver lesions via ultrasound.  She started feeling bad again and the diarreha returned this week.  She went back to the Dr. and was diagnosed with c difficile and a protozoa.  They are doing a contrast MRI to check the liver lesions tomorrow.  What could be causing this? [/INST] Thanks for contacting Chat Doctor with your medical questions. I am sorry to hear about your sister who has had guardian and now clostridium difficile and a protozoan infection. From your description she has been treated with medication for the guardian, which by the way is a protozoan infection, and has diarrhea again. After taking any antibiotics the usual gut bacteria are also killed off and an opportunistic infection called clostridium difficile can grow. Since this is her first episode of C. difficile she will more than likely be on one or two additional antibiotics for 2 weeks. This may also kill of the other "protozoan infection, so she would not need additional antibiotics. The liver lesions are more worrisome. They could be just simple cysts, or they could be actual cysts cause from infection. I would recommend keeping her appointment for the MRI to find a definitive answer to her problems. Hope I answered your question. Please contact us again with your medical concerns </s>