Peritonitis and Exit-Site Infection

Peritonitis and Exit-Site Infection

Quick Answer: Cloudy effluent with abdominal pain should be treated as peritonitis until proven otherwise. Priority action: send effluent for cell count, Gram stain, and culture. Peritonitis is diagnosed when effluent WBC count exceeds 100/μL with >50% neutrophils. Empiric therapy must cover gram-positive and gram-negative organisms. Exit-site infection is localized to the catheter surface; tunnel infection involves the subcutaneous tract. Refractory peritonitis requires catheter removal and transition to hemodialysis.

Peritonitis: Recognition and Diagnosis

Peritonitis is the most serious infectious complication of PD and a leading cause of technique failure. Patients may report abdominal pain, fever, nausea, or cloudy dialysate; some present with mild symptoms only. Any change in effluent clarity warrants evaluation—do not wait for fever.

Diagnostic criteria (ISPD-aligned, commonly tested on CDN):

Priority nursing action when peritonitis is suspected: obtain effluent for cell count and culture (and Gram stain when available) before initiating or changing antibiotics, when safely possible. A scenario with 250 WBC/μL and 80% neutrophils confirms peritonitis and supports empiric broad coverage.

The most common organism is coagulase-negative staphylococcus (CONS), often introduced by touch contamination during exchanges. Staphylococcus aureus, streptococci, and gram-negative rods (e.g., E. coli, Pseudomonas) also occur. Fungal peritonitis is less common but carries high morbidity and usually mandates catheter removal.

Empiric Antibiotic Management

Initial therapy provides gram-positive and gram-negative coverage intraperitoneally (IP antibiotics are standard in PD peritonitis to achieve high local concentrations). Regimens vary by center but often combine a first-generation cephalosporin or vancomycin (for gram-positive coverage) with an agent covering gram-negatives (e.g., ceftazidime or aminoglycoside), adjusted for allergies and local resistance patterns.

Nursing responsibilities include:

• Teaching patients to mix IP antibiotics into dialysate per protocol
• Monitoring temperature, pain, effluent clarity daily
• Ensuring repeat cell counts show response (WBC trending down)
• Reporting refractory peritonitis—failure to improve after 5 days of appropriate antibiotics

Refractory peritonitis indication: remove the catheter and transition to hemodialysis. Continuing PD with an infected catheter risks sepsis, membrane damage, and mortality.

Worked Scenario

A patient on CAPD notices cloudy effluent and diffuse abdominal pain 12 hours after a rushed exchange without a mask. Effluent shows 250 WBC/μL, 80% neutrophils. The nurse prioritizes culture, initiates empiric gram-positive and gram-negative IP antibiotics per order, reinforces aseptic technique, and schedules daily follow-up. If cultures grow CONS, therapy may narrow; if no improvement by day 5, plan catheter removal.

Exit-Site Infection

Exit-site infection (ESI) is confined to the external catheter segment. Signs include purulent drainage, erythema, and tenderness at the exit. Dry crusting alone is not diagnostic of infection. ESI increases peritonitis risk if organisms track along the tunnel.

Management typically includes topical or systemic antibiotics directed at cultured organisms, intensified exit-site care, and sometimes silver nitrate or gentle debridement per protocol. Nurses differentiate ESI from sterile irritation caused by trauma or allergy to dressings.

Tunnel Infection

Tunnel infection presents with erythema, tenderness, and swelling along the subcutaneous catheter pathway, sometimes with drainage tracking from tunnel to exit. It is more difficult to eradicate than superficial ESI and often requires systemic antibiotics and catheter removal if refractory. CDN vignettes may describe induration extending several centimeters from the exit—think tunnel, not surface-only ESI.

Prevention: Nurse-Led Strategies

Peritonitis prevention aligns with catheter and exchange teaching:

• Strict aseptic technique and flush-before-fill
• Daily exit-site care with chlorhexidine or povidone-iodine
• Mupirocin prophylaxis when prescribed
• Catheter immobilization to prevent trauma
• Prompt treatment of constipation and ESI before organisms seed the peritoneum
• Patient education: cloudy effluent = call immediately, save a sample

Nurses should also review exchange technique with return demonstration after any peritonitis episode, because recurrent infection with the same organism often signals technique failure rather than a new environmental exposure. Documenting the patient's technique break (skipped mask, low bag position, reused cap) helps the team distinguish contamination events from catheter colonization requiring device revision.

Fungal and Recurrent Peritonitis

Fungal peritonitis (often Candida) frequently follows recent antibiotic use. Catheter removal is usually mandatory, followed by antifungal therapy and temporary hemodialysis. Recurrent peritonitis with the same organism suggests technique failure or colonized catheter—evaluate exchange procedure with a return demonstration and consider catheter replacement after clearance.

CDN Exam Traps

1. Cloudy effluent + pain: Culture/cell count first—not immediate HD catheter pull unless refractory.
2. Most common organism: CONS from touch contamination, not Pseudomonas as the #1 answer.
3. Exit-site vs peritonitis: Purulent drainage at skin with clear effluent = ESI; cloudy effluent = peritonitis workup.
4. Refractory peritonitis: Catheter removal and HD transition after failed 5-day antibiotic course.
5. Tunnel infection: Erythema and tenderness along the subcutaneous tract, not only at the skin opening.