What is the best management approach for a 65-year-old man with fever, diarrhea, and weakness, who was recently hospitalized for exacerbation of heart failure and now presents with hyperactive bowel sounds and tenderness in the left lower quadrant?

Management of Suspected Clostridioides difficile Infection in a Recently Hospitalized Heart Failure Patient

This patient requires immediate stool testing for Clostridioides difficile toxin and empiric antibiotic therapy with oral vancomycin or fidaxomicin while awaiting results, given the high-risk presentation of recent hospitalization, fever, diarrhea, and left lower quadrant tenderness. 1

Clinical Reasoning

This 65-year-old man presents with a classic triad suggesting healthcare-associated C. difficile infection:

• Recent hospitalization (major risk factor for C. difficile acquisition) 1
• Fever with diarrhea (Grade 2-3 severity based on symptoms) 1
• Left lower quadrant tenderness (concerning for colonic involvement) 2

The recent heart failure exacerbation hospitalization likely involved diuretic therapy and possible antibiotic exposure, both significant risk factors for C. difficile infection 1.

Immediate Diagnostic Workup

Obtain the following tests urgently:

• Stool C. difficile toxin assay (PCR or enzyme immunoassay) 1
• Complete blood count with differential (assess for leukocytosis) 1
• Comprehensive metabolic panel (evaluate for acute kidney injury, electrolyte disturbances, and volume depletion) 1
• Serum lactate (if severe illness suspected) 1

Consider urgent CT abdomen/pelvis if:

• Severe abdominal pain persists
• Signs of peritonitis develop
• Concern for toxic megacolon or perforation
• No improvement after 48 hours of appropriate therapy 1

Initial Management Strategy

1. Empiric Antibiotic Therapy

Start immediately without waiting for test results given the high clinical suspicion and potential for rapid deterioration 1:

• First-line: Oral vancomycin 125 mg four times daily OR fidaxomicin 200 mg twice daily 1
• Continue for 10 days minimum 1

2. Fluid and Electrolyte Management

Critical in this heart failure patient:

• Assess volume status carefully (recent HF exacerbation complicates assessment) 1
• Replace ongoing fluid losses: approximately 10 mL/kg for each watery stool 3
• Monitor daily weights, input/output 1
• Check electrolytes daily while diarrhea persists (risk of hypokalemia, hypomagnesemia) 1
• Caution: Avoid aggressive IV fluid resuscitation that could precipitate HF exacerbation 1

3. Symptomatic Management

DO NOT use loperamide or other antimotility agents in this patient with fever and suspected infectious colitis, as this increases risk of toxic megacolon 3, 4. The FDA labeling for loperamide specifically contraindicates use in acute bacterial enterocolitis 4.

4. Heart Failure Medication Adjustments

Review and temporarily modify HF medications:

• Continue beta-blockers unless hemodynamically unstable 1
• Hold or reduce ACE inhibitors/ARBs if acute kidney injury develops 1
• Adjust diuretics based on volume status—may need temporary reduction if dehydrated from diarrhea 1
• Monitor for BRASH syndrome (Bradycardia, Renal failure, AV blockade, Shock, Hyperkalemia) given the combination of diarrhea-induced volume depletion, heart failure medications (beta-blockers, ACE inhibitors, diuretics), and potential for acute kidney injury 5

Critical Monitoring Parameters

Daily assessment should include:

• Stool frequency and character 1
• Vital signs (heart rate, blood pressure—both supine and standing) 1
• Volume status (jugular venous pressure, lung sounds, peripheral edema) 1
• Abdominal examination (worsening tenderness, distension, peritoneal signs) 1, 2
• Serum creatinine and electrolytes (potassium, magnesium) 1, 5
• Complete blood count (leukocytosis may worsen with severe C. difficile) 1

Red Flags Requiring Escalation

Transfer to ICU or surgical consultation if:

• White blood cell count >15,000 cells/μL or <2,000 cells/μL 1
• Serum creatinine >1.5 times baseline 1
• Hypotension or shock develops 1
• Severe abdominal distension or peritoneal signs 1, 2
• Lactate >2.2 mmol/L 1
• Clinical deterioration despite 48 hours of appropriate therapy 1

Common Pitfalls to Avoid

Do not:

• Use antimotility agents (loperamide, diphenoxylate) in suspected infectious diarrhea with fever 3, 4
• Aggressively fluid resuscitate without considering HF status 1
• Discontinue all HF medications abruptly—particularly beta-blockers 1
• Delay antibiotic therapy while awaiting test results in high-risk patients 1
• Assume diarrhea is simply HF-related bowel edema without ruling out infection 1, 2

Special consideration: Pseudomembranous colitis can rarely present without diarrhea as colonic pseudo-obstruction, particularly in elderly patients with multiple comorbidities 2. The presence of hyperactive bowel sounds in this case makes obstruction less likely, but maintain vigilance for this atypical presentation.