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

Signs and Symptoms of Clostridioides difficile Infection

Watery, non-bloody diarrhea (≥3 unformed stools in 24 hours) accompanied by abdominal cramping is the hallmark presentation of C. difficile infection. 1

Primary Clinical Manifestations

Gastrointestinal Symptoms

• Diarrhea: Watery, loose stools taking the shape of the receptacle (Bristol stool chart types 5-7), with frequency perceived as excessive by the patient 2, 1
• Abdominal pain and cramping: Ranges from mild discomfort to severe pain, frequently accompanying the diarrhea 2, 1
• Abdominal distension: May be present, particularly in more severe cases 3
• Fecal incontinence: Can be part of the disease presentation 2
• Hyperactive bowel sounds: Commonly present due to increased intestinal motility and inflammation in early disease 3

Systemic Symptoms

• Fever: Core body temperature >38.5°C indicates more severe infection 2
• Rigors: Uncontrollable shaking with feeling of cold followed by temperature rise 2

Severity-Stratified Presentations

Mild-to-Moderate CDI

• Stool frequency <4 times daily 2
• No signs of severe colitis 2
• White blood cell count <15 × 10⁹/L 2
• Mild abdominal pain and cramps 1

Severe CDI

The following laboratory and clinical markers indicate severe disease:

Laboratory Findings:

• Marked leukocytosis: WBC >15 × 10⁹/L 2
• Marked left shift: Band neutrophils >20% of leukocytes 2
• Renal dysfunction: Rise in serum creatinine ≥50% above baseline or ≥133 μM/L (≥1.5 times premorbid level) 2
• Hypoalbuminemia: Serum albumin <30 g/L or <2.5 g/dL 2
• Elevated serum lactate 2

Clinical Signs:

• Hemodynamic instability including signs of distributive (septic) shock 2
• Signs of peritonitis: decreased bowel sounds, abdominal tenderness, rebound tenderness, and guarding 2
• Temperature >38.5°C 2

Fulminant/Complicated CDI (1-3% of cases)

• Ileus: Vomiting, absent passage of stool, with radiological signs of bowel distension 2
• Toxic megacolon: Radiological distension of colon combined with severe systemic inflammatory response 2
• Hypoactive or absent bowel sounds: Signals progression to ileus or toxic megacolon 3
• Severe abdominal tenderness 2
• >12 bowel movements per day 2
• Colonic perforation with peritonitis 2
• Septic shock and organ dysfunction 2

Imaging and Endoscopic Findings

Radiological Signs

• Distension of large intestine 2
• Colonic wall thickening including low-attenuation mural thickening 2
• Pericolonic fat stranding 2
• Ascites not explained by other causes 2

Endoscopic Findings

• Pseudomembranous colitis: Pathognomonic when present, though only seen in 51-55% of cases 2, 4
• Diffuse erythema to prominent pseudomembranes 5

Special Clinical Scenarios

Absence of Diarrhea

• Critical pitfall: Diarrhea may be absent initially in surgical patients or those with ileus, making diagnosis challenging 1
• Absence of diarrhea may signal progression to fulminant infection 2

Immunocompromised Patients (HIV/AIDS)

• Severe clinical presentation with profound watery diarrhea (mean 20 bowel movements per day) 5
• Fever >38.5°C or hypothermia 5
• Hypotension or orthostatic changes 5
• Metabolic derangements: hyponatremia, hypokalemia, prerenal azotemia 5
• Prolonged diarrhea that may not remit spontaneously 5

Inflammatory Bowel Disease Patients

• Clinical presentation may overlap with IBD flare, making diagnosis more challenging 1

Long-Term Care Facility Residents

• Suspect CDI in residents with systemic antimicrobial therapy in previous 30 days who experience ≥3 watery stools in 24 hours and/or abdominal pain 1

Common Clinical Pitfalls

• Blood in stool is rare: Admixture of blood with stools is uncommon in CDI, and its correlation with severity is uncertain 2
• Testing asymptomatic patients: Should be avoided as it detects colonization rather than infection 1, 4
• Delayed recognition of fulminant disease: Hypoactive bowel sounds with severe abdominal pain should prompt immediate assessment for ileus or toxic megacolon 3