A 65-year-old man on chronic peritoneal dialysis (PD) for two years complains of 1 day of diffuse abdominal pain. He has not noticed any changes in his catheter exit site, changes in bowel movements, fever, or chills.
His temperature is 37.2 C (99.0 F), blood pressure is 140/90 mm Hg, and pulse is 90/min. Bowel sounds are normal. There is mild, diffuse abdominal tenderness without definite rebound tenderness. The catheter exit site looks normal.
Analysis of peritoneal fluid reveals a white blood cell count of 110 cells/µL. Gram stain of the peritoneal fluid is negative.
Laboratory results are as follows:

Which of the following would be the most appropriate next step in management?

Question

A 65-year-old man on chronic peritoneal dialysis (PD) for two years complains of 1 day of diffuse abdominal pain.  He has not noticed any changes in his catheter exit site, changes in bowel movements, fever, or chills.
His temperature is 37.2 C (99.0 F), blood pressure is 140/90 mm Hg, and pulse is 90/min.  Bowel sounds are normal.  There is mild, diffuse abdominal tenderness without definite rebound tenderness.  The catheter exit site looks normal.
Analysis of peritoneal fluid reveals a white blood cell count of 110 cells/µL.  Gram stain of the peritoneal fluid is negative.
Laboratory results are as follows:

Which of the following would be the most appropriate next step in management?

Quizplus · Accepted Answer

11ec193a_97f7_3276_853d_8b8faf27ce8e_MD0002_00 This patient's presentation is concerning for PD-related peritonitis, most commonly due to touch-contamination from skin bacteria or catheter-related infection. Patients usually present with abdominal pain, low grade fever (in up to 50% of patients), and nausea. Examination typically reveals abdominal tenderness, sometimes with cloudy abdominal fluid and rebound tenderness. Diagnosis is highly suggested by peritoneal fluid showing > 100 WBCs. However, fluid with > 50% neutrophils strongly favors PD-related peritonitis regardless of the absolute fluid WBC count. Gram stain is usually negative and diagnosis is confirmed by positive peritoneal fluid cultures (80-95% of cases). Although Gram-positive skin bacteria is the most common cause of PD peritonitis, patients should be treated empirically for both Gram-positive and Gram-negative organisms. Current guidelines recommend intraperitoneal vancomycin and a 3^rd or 4^th generation cephalosporin (e.g., cefepime) or an aminoglycoside. Intraperitoneal antibiotics appear to be more efficacious than intravenous antibiotics (Choice E). ^rd (Choice A) Abdominal CT scan is indicated in patients with suspected secondary peritonitis due to enteric pathology (e.g., appendicitis, incarcerated hernia, ruptured diverticula). However, secondary peritonitis tends to present with more systemic symptoms (e.g., fever, chills, hypotension, significant leukocytosis), which are usually not present in PD-related peritonitis. If a CT scan is performed, it is important to recall that PD patients can have asymptomatic free peritoneal air from the PD catheter. (Choice B) Colonoscopy is not usually indicated in PD peritonitis. (Choice C) Catheter removal is considered only for tunnel infections or refractory intraperitoneal infections. However, this patient's normal appearing catheter site makes this less likely. Educational objective: Peritoneal dialysis-associated peritonitis usually presents with abdominal pain and nausea. Fever and leukocytosis may not be present. Diagnosis is suggested by peritoneal fluid showing > 100 WBCs or > 50% neutrophils (regardless of fluid WBC count), and is confirmed with positive peritoneal fluid cultures. __________ References: Treatment for peritoneal dialysis-associated peritonitis. (http://www.ncbi.nlm.nih.gov/pubmed/18254075) Microbiological profile of peritoneal dialysis peritonitis and predictors of hospitalization. (http://www.ncbi.nlm.nih.gov/pubmed/22073826)

A 65-Year-Old Man on Chronic Peritoneal Dialysis (PD) for Two