What infections are common in diabetic patients presenting with persistent fever and diarrhea?

Common Infections in Diabetic Patients with Persistent Fever and Diarrhea

Diabetic patients presenting with persistent fever and diarrhea should be evaluated for Clostridium difficile infection as the most likely cause, followed by other bacterial, parasitic, and viral pathogens based on a broad differential diagnosis approach. 1

Primary Infectious Considerations

Clostridium difficile Infection

• C. difficile is the most common enteric cause of fever in hospitalized patients and should be suspected in any patient with fever and diarrhea who received antibiotics or chemotherapy within 60 days 1
• C. difficile accounts for 10-25% of all antibiotic-associated diarrhea and virtually all cases of antibiotic-associated pseudomembranous colitis 1
• Diabetic patients have an increased risk of recurrent C. difficile infection with odds ratio of 2.99 (95% CI 1.88-4.76) 2
• Testing for C. difficile should be performed in patients with persistent diarrhea, especially those with recent antibiotic exposure 1

Other Bacterial Pathogens

• For persistent fever and diarrhea, consider testing for:
  • Salmonella species 1
  • Shigella species 1
  • Campylobacter jejuni 1
  • Yersinia enterocolitica (especially with persistent abdominal pain and fever) 1
  • Escherichia coli (particularly Shiga toxin-producing strains) 1

Parasitic Infections

• Immunocompromised patients (including poorly controlled diabetics) should be evaluated for:
  • Cryptosporidium species 1
  • Giardia lamblia 1
  • Cyclospora cayetanensis 1
  • Entamoeba histolytica (especially if higher temperatures are present) 1

Diagnostic Approach

Initial Testing

• Stool testing should include:
  • C. difficile toxin testing (primary consideration) 1, 3
  • Bacterial culture for Salmonella, Shigella, Campylobacter, and Yersinia 1
  • Testing for Shiga toxin-producing E. coli 1
  • Examination for parasites, particularly in immunocompromised patients 1

Additional Considerations

• If diarrhea persists for 14 days or longer, evaluation for intestinal parasitic infections is strongly recommended 1
• For diabetic patients with severe hyperglycemia, broader diagnostic testing is warranted as they may be functionally immunocompromised 1, 2
• Consider CT imaging of the abdomen for patients with severe abdominal pain to evaluate for complications such as neutropenic enterocolitis 1

Treatment Considerations

For C. difficile Infection

• First-line treatment is oral metronidazole for mild to moderate cases 4, 5
• For severe cases, oral vancomycin is recommended 6, 7
• Fidaxomicin is an alternative option with lower recurrence rates 8
• Recurrence occurs in 7-20% of patients and may require extended treatment regimens 4

For Other Bacterial Infections

• Treatment should be guided by identified pathogens and antimicrobial susceptibility testing 1
• Empiric therapy should consider local resistance patterns 1

Special Considerations for Diabetic Patients

• Diabetic patients are at higher risk for:

  • More severe infections due to immunocompromise 2
  • Extracolonic manifestations of infections 9
  • Recurrent infections, particularly C. difficile 2
  • Prolonged recovery periods 2

• Careful glycemic control is essential during treatment as hyperglycemia can worsen infection outcomes 2

• Monitor for potential complications including bacteremia, visceral abscesses, and reactive arthritis, which can occur with C. difficile infections 9

Pitfalls and Caveats

• Do not test asymptomatic patients for C. difficile, as colonization is common (up to 7% in healthy adults) 4, 2
• Do not repeat testing for C. difficile after successful treatment if symptoms have resolved 1
• Avoid unnecessary antibiotic use as it increases risk for C. difficile and other resistant infections 1, 4
• Remember that diabetic patients may present with atypical or muted symptoms due to neuropathy 2
• Consider extracolonic manifestations of C. difficile in diabetic patients with fever but minimal gastrointestinal symptoms 9