What is the recommended treatment for a peristomal (ostomy) infection, including management of mild to moderate cases and severe cases with systemic signs?

Treatment of Peristomal (Ostomy) Infection

For mild peristomal infections diagnosed early, oral broad-spectrum antibiotics for 5-7 days are sufficient; for severe infections with systemic signs (fever, tachycardia, elevated WBC), intravenous broad-spectrum antibiotics coupled with local wound care are necessary, and surgical intervention is required if peritonitis develops 1.

Severity Assessment and Treatment Algorithm

Mild Infection (Local Signs Only)

• Clinical presentation: Erythema, mild exudate, induration at stoma site without systemic symptoms
• Temperature: <38°C
• Erythema: ≤5 cm from stoma edge
• Treatment: Oral broad-spectrum antibiotics for 5-7 days 1

Recommended oral regimens (based on skin and soft tissue infection guidelines):

• Cephalexin 500 mg every 6 hours 2
• Dicloxacillin (if methicillin-susceptible S. aureus suspected)
• If MRSA risk factors present (prior MRSA history, high local prevalence): Doxycycline, clindamycin, or trimethoprim-sulfamethoxazole 2

Moderate to Severe Infection (Systemic Signs Present)

• Clinical presentation: Temperature ≥38°C, tachycardia (>90 bpm), tachypnea (>24 breaths/min), WBC <4,000 or >12,000 cells/μL
• Erythema: >5 cm from stoma with induration or necrosis
• Treatment: Intravenous broad-spectrum antibiotics PLUS local wound care 1

Recommended IV regimens (for perineal/abdominal stoma sites):

• Piperacillin-tazobactam 3.375 g every 6 hours or 4.5 g every 8 hours 3, 2
• Ceftriaxone 1 g every 24 hours + metronidazole 500 mg every 8 hours 3, 2
• Levofloxacin 750 mg every 24 hours + metronidazole 500 mg every 8 hours 3, 2
• Ertapenem 1 g every 24 hours (single agent) 3

Critical: Signs Requiring Surgical Intervention

• Peritonitis (abdominal rigidity, rebound tenderness, diffuse pain)
• Incarcerated parastomal hernia with infection
• Necrotizing infection (rapidly spreading erythema, skin sloughing, bullae, gas in tissues)

Immediate surgical consultation required 1, 2, 1

Adjunctive Local Wound Care

Skin Protection Measures

• Apply zinc oxide-based skin protectants to surrounding skin to prevent breakdown from leakage 4, 1
• Use foam dressings rather than gauze (foam lifts drainage away from skin, gauze traps it) 1
• Clean with antimicrobial cleanser minimum once daily 4

Fungal Superinfection Management

Local fungal infections commonly accompany peristomal infection, presenting as itchy maculopapular rash with satellite borders:

• Apply antifungal powder to affected skin, seal with skin sealant 1
• If no improvement after 2 weeks, refer to enterostomal therapist or surgeon 5

Reducing Gastric Secretions (for gastrostomy sites)

• Proton pump inhibitors can decrease leakage by minimizing gastric acid secretion 4
• Review regularly and discontinue when infection resolves

Important Clinical Considerations

Risk Factors for Infection

Patients at higher risk require closer monitoring 1:

• Diabetes mellitus
• Obesity
• Poor nutritional status
• Chronic corticosteroid or immunosuppressive therapy
• Excessive pressure between internal/external bolsters (gastrostomy)

Common Pitfalls to Avoid

1. Do NOT use ampicillin-sulbactam due to high E. coli resistance rates 3
2. Do NOT use cefotetan or clindamycin due to increasing Bacteroides fragilis resistance 3
3. Avoid quinolones unless local hospital data shows ≥90% E. coli susceptibility 3
4. Do NOT empirically cover Enterococcus in community-acquired infections 3
5. Do NOT empirically cover Pseudomonas unless specific risk factors present 6

Duration of Therapy

• Mild infections: 5-7 days oral antibiotics 1
• Moderate to severe infections: Continue IV antibiotics until systemic signs resolve, then consider oral step-down therapy based on clinical response
• Treatment should continue until resolution of infection signs, not until complete wound healing 6

When Antibiotics Alone Are Insufficient

If infection persists despite appropriate antibiotics:

• Verify proper stoma appliance fit and tension
• Rule out underlying complications (buried bumper syndrome, parastomal hernia, stomal ischemia)
• Consider wound and ostomy nurse consultation for specialized management 1
• Evaluate for disease-related complications (pyoderma gangrenosum in IBD patients) 7, 5

Special Consideration: Pyoderma Gangrenosum

In IBD patients presenting with painful ulcers surrounded by purple halo, consider pyoderma gangrenosum rather than simple infection 7, 5. This requires immunosuppressive therapy (corticosteroids, infliximab) rather than antibiotics alone.