Hi, I have gone through your question and understand your concern. I would like to tell you that persistant or recurrent diarrhoea maynot due to infection only. It can occur due to antibiotics (due to disturbed intestinal atmosprere) or intolerence to certain food or food additives like soy protein, sorbitol, cow s milk etc. inwhich case reports come normal. Stones in kidney may not be related to diarrhoea. You can try avoiding taking antibiotics or foods as said above. You should take probiotics like yogurt. Eat freshly prepared food and avoid eating outside food. Maintain food hygiene strictly. Take care of the normal hygiene guidelines like washing hands properly.