What are the symptoms and signs of a C diff (Clostridioides difficile) infection?

Signs and Symptoms of Clostridioides difficile Infection

The diagnosis of Clostridioides difficile infection (CDI) requires both clinical symptoms and a positive laboratory test, with diarrhea (defined as three or more unformed stools in 24 hours) being the primary symptom. 1, 2

Primary Clinical Manifestations

• Diarrhea: Three or more unformed stools within 24 hours is the hallmark symptom 1, 2
• Abdominal pain and cramps: Common accompanying symptoms that may range from mild to severe 1, 2
• Abdominal distension: Bloating and swelling of the abdomen 1
• Fever: Temperature >38.5°C may indicate severe infection 1

Laboratory and Clinical Markers of Severity

• Leukocytosis: WBC >15 × 10^9/L suggests severe infection 1
• Elevated serum creatinine: ≥133 μM/L or ≥1.5 times premorbid level indicates severe disease 1
• Hypoalbuminemia: Albumin <2.5 g/dL is associated with severe disease 1
• Elevated serum lactate: May indicate fulminant disease with organ failure 1

Severe and Complicated Presentations

• Pseudomembranous colitis: Visible on endoscopy as yellowish plaques on the colonic mucosa 1, 3
• Toxic megacolon: Severe, potentially life-threatening complication with colonic dilation 1
• Ileus: Signs of severely disturbed bowel function with decreased or absent bowel sounds 1
• Fulminant colitis: Characterized by severe systemic inflammatory response, shock, and organ failure 1
• Colonic perforation: Rare but life-threatening complication with high mortality 1

Risk Factors That Should Raise Suspicion

• Recent antibiotic use: Particularly clindamycin, penicillins, cephalosporins, and fluoroquinolones 2, 4
• Recent hospitalization or healthcare facility exposure: Increases risk of exposure to C. difficile spores 2
• Advanced age: Elderly patients are at higher risk for both acquisition and severe outcomes 2
• Immunocompromised status: Including patients on glucocorticoids or chemotherapy 1
• Proton pump inhibitor use: Associated with increased risk of CDI 1

Diagnostic Approach

• Testing should only be performed on patients with clinically significant diarrhea (≥3 unformed stools in 24 hours) who are not taking laxatives 1, 4
• Two-step algorithm is recommended: starting with screening using GDH or NAAT (high sensitivity), followed by confirmation with toxin detection (higher specificity) 1, 2
• Perirectal swabs may be used for patients with severe CDI complicated by ileus who cannot produce stool specimens 1

Common Pitfalls and Caveats

• Asymptomatic colonization: 10-52% of certain populations may carry C. difficile without symptoms; testing and treatment are not recommended in these cases 1
• Post-infectious irritable bowel syndrome: Up to 35% of patients may have transient functional bowel disorder in the first two weeks after CDI resolution, but only 4.3% have persistent symptoms beyond three months 1
• "Test of cure" is not recommended: 56% of patients may asymptomatically shed C. difficile spores for up to six weeks after successful treatment 1
• Recurrent symptoms: May be due to either recurrent infection or post-infectious irritable bowel syndrome; distinguishing between these is important but challenging 1

Early recognition of symptoms and prompt diagnosis are crucial for effective management of CDI and can potentially improve outcomes while controlling transmission 1, 2.