What can characterize stools in a patient with IBS?

In patients with Irritable Bowel Syndrome (IBS), one common characteristic of stools can be loose stools. IBS is a functional gastrointestinal disorder that is often associated with symptoms such as abdominal pain, bloating, and changes in bowel habits. The alteration in bowel habits can manifest as either diarrhea or constipation, or a mix of both (known as IBS-M).

Loose stools specifically indicate a form of diarrhea that can occur in those with IBS-D (diarrhea-predominant IBS). The stools may also be accompanied by urgency, and the frequency can increase. This symptom is relevant to the pathology of IBS, where bowel motility can be disrupted, leading to changes in stool consistency.

Other options like consistently hard stools point more towards constipation rather than the loose stools seen in certain types of IBS. Black tarry stools typically indicate upper gastrointestinal bleeding, which is not associated with IBS. Transparent mucus in stools can occur in IBS but is not as definitive or common as the presence of loose stools in IBS-D. Therefore, loose stools are a clear indicator of one potential presentation of this condition.