Foul-Smelling Diarrhea - Causes, Symptoms, Diagnosis, and Treatment

Introduction

Stools usually have an unpleasant smell. This smell is due to the activity of the bacteria in the digestive tract. Foul-smelling stools, particularly, have a bad odor. These stools are often soft and runny. This is mostly due to the foods one eats, and sometimes, it may indicate an underlying medical condition.

What Are the Causes of Foul-Smelling Diarrhea?

Changes in the diet are the most common cause of foul-smelling diarrhea.

Some other causes include:

1. Malabsorption: Malabsorption is also a common cause of foul-smelling diarrhea. Malabsorption occurs when the body cannot absorb adequate nutrients from food. The causes of malabsorption include:

• Celiac Disease: It is an immune reaction to eating gluten that results in malabsorption.

• Inflammatory Bowel Diseases: People with inflammatory bowel diseases such as Crohn's disease (inflammation of the digestive tract) and ulcerative colitis (inflammation and ulcers in the colon) often complain of foul-smelling stools and flatulence. Eating certain foods can trigger inflammation of the intestine, which causes foul-smelling diarrhea.

• Carbohydrate Intolerance: Lactose is a sugar found in milk and other dairy products. People who are lactose intolerant can not digest lactose and experience loose, foul-smelling stools.

• Food Allergies: Some people are allergic to milk, and they have bloody, foul-smelling stools.

2. Infection: Infection of the intestine can cause foul-smelling diarrhea. Bacteria such as Escherichia coli or Salmonella, viruses such as norovirus or rotavirus, or parasites such as Entamoeba histolytica can cause inflammation of the stomach and intestines, which can result in abdominal cramps and foul-smelling runny stools.

3. Overeating: When one eats more than the body can digest, it causes indigestion. The undigested food is acted upon by the bacteria in the gastrointestinal tract, resulting in abdominal pain and foul-smelling diarrhea.

4. Medications: Some antibiotics can result in temporary stomach upset and foul-smelling diarrhea until the normal bacterial flora is restored. This is because antibiotics destroy the normal good bacteria in the intestine. The foul smell disappears once the antibiotic course is finished. Foul-smelling diarrhea can be a side effect of taking multivitamins in higher doses than recommended. Excessive intake of fat-soluble vitamins A, D, E, and K can result in foul-smelling stool.

5. Foods: Eating foods that are high in sulfur like meat, dairy, garlic, broccoli, and cabbage, can cause foul-smelling stools.

6. Other Conditions:

• Chronic Pancreatitis: It is the inflammation of the pancreas, which affects the ability to digest food. This condition results in oily, fatty, and foul-smelling stool.

• Short Bowel Syndrome: It is a rare condition that occurs when a portion of the large or small intestine is removed or absent. People with this condition have malabsorption which results in pale, greasy, foul-smelling diarrhea.

• Giardiasis: It is an intestinal infection caused by the parasite giardia, which results in foul-smelling, greasy diarrhea.

• Cystic Fibrosis: It is a condition affecting the cells that produce sweat, mucus, and digestive enzymes. The digestive system can not absorb the nutrients properly without these digestive enzymes, causing foul-smelling diarrhea.

What Are the Symptoms of Foul-Smelling Diarrhea?

• Foul-smelling runny stools.

• Soft stools.

• Frequent bowel movements.

• Nausea.

• Vomiting.

• Flatulence.

• Abdominal bloating.

• Abdominal pain.

How Is Foul-Smelling Diarrhea Diagnosed?

The doctor will ask about the consistency of the stool when the foul smell occurs, recent changes to the diet, and history of antibiotic treatment.

• Blood Test: Complete blood count test, kidney and liver function tests, and electrolyte measurements are done. This also checks for immunoglobulin E antibodies which are produced during allergic reactions.

• Stool Test: Stool samples are taken and sent to the laboratory to check for bacterial, viral, and parasitic infections and to check for bacterial toxins.

• Hydrogen Breath Test: The patient is asked to consume foods containing lactose and breathe into a bag. If the air contains hydrogen, this indicates lactose intolerance.

• Endoscopy: A long, thin, flexible tube is inserted through the mouth into the small intestine to remove tissue and check for malabsorption.

• Abdominal X-Rays: They are used to check for any obstructions in the intestine and loss of bowel function.

• Sigmoidoscopy or Colonoscopy: This procedure uses a long, thin tube inserted through the mouth into the intestine to view the colon. Sigmoidoscopy helps in viewing the lower colon, while colonoscopy can view the entire colon. They are used to find out inflammatory bowel diseases.

What Are the Ways to Prevent Foul-Smelling Diarrhea?

Making changes to the diet can prevent foul-smelling diarrhea.

• Avoid drinking raw, unpasteurized milk.

• Avoid milk and other dairy products.

• Follow a low FODMAP diet (low in fermentable oligosaccharides, disaccharides, monosaccharides, and polyols).

• Cook raw foods like eggs, poultry, and meat thoroughly before eating.

• Cook meat thoroughly to the appropriate temperature.

• Use different chopping boards for vegetables and meat.

• Maintaining good personal hygiene may also help prevent diarrhea. Wash the hands thoroughly before cooking and after using the restroom.

What Is the Treatment of Foul-Smelling Diarrhea?

Excessive watery stools can dehydrate the patient. Intravenous fluids are given to replace the loss of electrolytes. Drink plenty of fluids and avoid high-fiber and wheat foods. Avoid fatty foods and dairy products. Eat a nutrient-rich diet. Painkillers are given if the patient has abdominal pain. Antidiarrheal medications such as Loperamide and Bismuth salicylate help reduce the frequency of watery stools.

Treatment is focused on treating the cause of fatty stool. If an antibiotic is causing foul-smelling diarrhea, discontinuing the antibiotic will stop the symptoms. People with celiac disease should eat a gluten-free diet, even after healing.

People with inflammatory bowel diseases are given anti-inflammatory medications. In chronic pancreatitis, surgery is done to remove all or part of the pancreas.

Conclusion

A foul-smelling stool is one that smells bad and rotten; usually, this smell comes from the food that people eat, but it can also be a sign of a health issue like colitis, an infection, or an allergy. Most conditions that cause foul-smelling diarrhea are treatable. Understanding and treating the cause helps relieve the symptoms and provide good results.