PARIS – said gastroenterologist Nassim Hammoudi, MD, PhD, of the Lariboisière Hospital in Paris, during France’s annual general medicine conference (JNMG 2023). He said that doctors need to understand the characteristics of chronic diarrhea and adapt its management accordingly. In his presentation, Dr. Hammoudi highlighted the clinical signs that should be considered.
Mechanisms of chronic diarrhea
Chronic diarrhea can result from different mechanisms, such as motility disorders related to accelerated intestinal transit, malabsorption, osmotic diarrhea, and secretory diarrhea, which are often interlinked. When an endoscopy is performed, it is recommended to conduct multilevel biopsies to detect microscopic colitis, which Dr. Hammoudi believes is “probably underdiagnosed.”
Diarrhea is defined as the passage of frequent stools (more than three a day), soft to liquid in consistency, and a daily weight exceeding 300 g. It is considered chronic when it persists for more than a month.
Identifying false diarrhea
Practitioners must first distinguish between genuine and false diarrhea, with the latter presenting in most consultations. “Thorough questioning is fundamental,” Dr. Hammoudi emphasized. It is essential to determine the daily stool count, the presence of nocturnal stools, and stool consistency. “A soft stool passed once a day is not diarrhea,” he said.
The most challenging form of false diarrhea to identify is what he called “constipated person’s diarrhea.” These patients, who are typically elderly, reside in care homes, and are bed-bound and taking morphine, have daily liquid stools but are actually constipated. “Taking antidiarrheal medications makes the situation worse,” said Dr. Hammoudi.
Another type of false diarrhea is tenesmus, in which patients feel like they have a full rectum, even though it is physiologically empty. The recurring urge to defecate results in mucus discharges that resemble diarrhea. Inflammatory rectal involvement could be the cause, necessitating a gastroenterology consultation.
Anal incontinence can also cause false diarrhea. It is more common in elderly people residing in care homes and in women in the postpartum period. This condition is difficult to manage and requires referral to a gastroenterologist.
Chronic diarrhea: Could cancer be the culprit?
After ruling out false diarrhea, clinicians should be vigilant for warning signs. The first question to consider, said Dr. Hammoudi, is whether the chronic diarrhea is associated with a lesion. Several criteria should prompt a colonoscopy, especially to search for colorectal cancer lesions:
- Age greater than 50 years
- Personal or family history of colorectal cancer
- Recent changes in bowel habits
- Rectal bleeding
- Nighttime stools
- Unexplained weight loss
- Iron-deficiency anemia
Obvious causes of chronic diarrhea should be prioritized in the management plan. Medications top the list, with more than 500 treatments – for example, ACE inhibitors, proton pump inhibitors (PPIs), antidiabetic drugs, colchicine, magnesium, laxatives – known to have diarrhea as a side effect.
Certain dietary habits can also exacerbate diarrhea, such as milk consumption in cases of lactose intolerance, or excessive sugar intake, which can lead to osmotic diarrhea.