Clostridium difficile-associated diarrhea is usually preceded by
extended use of antibiotics.
a blood transfusion.
eating contaminated food.
improper food storage.
travel to an underdeveloped country.
The correct answer and explanation is :
Correct Answer: Extended use of antibiotics.
Explanation:
Clostridium difficile-associated diarrhea (CDAD) is primarily caused by the disruption of the normal gut microbiota due to extended use of antibiotics. C. difficile is a spore-forming, toxin-producing bacterium that can reside in the intestines without causing harm. However, when antibiotics disrupt the balance of the normal gut flora, C. difficile can overgrow and release toxins, leading to diarrhea and colitis.
Role of Antibiotics:
Broad-spectrum antibiotics such as clindamycin, fluoroquinolones, cephalosporins, and penicillins are particularly associated with CDAD because they eliminate beneficial gut bacteria that normally keep C. difficile in check. Without this competition, C. difficile proliferates and produces toxins A and B, which damage the intestinal lining, causing inflammation, diarrhea, abdominal cramping, and even life-threatening complications such as toxic megacolon or sepsis.
Risk Factors:
- Prolonged antibiotic use (especially in hospitalized patients)
- Elderly patients (weaker immune system)
- Immunosuppression (chemotherapy, organ transplantation, etc.)
- Hospitalization or long-term care facility stay (increased exposure to C. difficile spores)
- Use of proton pump inhibitors (PPIs) (reduce stomach acid, which helps kill bacteria)
Prevention Strategies:
- Judicious antibiotic use (only when necessary)
- Proper hand hygiene (soap and water are more effective than alcohol-based sanitizers)
- Contact precautions in healthcare settings (isolation of infected patients)
- Probiotics (potential benefit in maintaining gut microbiota balance)
In summary, the most common precursor to Clostridium difficile-associated diarrhea is the extended use of antibiotics, which disrupts the gut microbiome and allows C. difficile to thrive, leading to severe gastrointestinal symptoms.