Hi and thanks for the query, Changes in the quality of stools could range form simple functional problems like constipation, changes in diet inadequate in fibre and water, to medical conditions like bladder and liver problems. Surgical causes of constipation like intestinal occlusion and infectious paralytic syndromes are also common. Orientations depend on clinical state of the patient on examination, stool examination results, results from plain abdominal films and abdominal CT scan. Which test to be prescribed at what moment are guided by a good physical examination. Consulting your emergnency room or primary care physician mght be very useful. Thanks and best regards, Luchuo, MD.