Initial Antibiotic Therapy for Peritoneal Dialysis Peritonitis

Diagnosis Confirmation

A peritoneal fluid PMN count >250 cells/mm³ confirms the diagnosis of peritoneal dialysis-associated peritonitis and warrants immediate empirical antibiotic therapy 2, 3
Ascitic fluid should be collected for culture before initiating antibiotics, with bedside inoculation into blood culture bottles to increase sensitivity to >90% 3, 4
Simultaneous blood cultures should be obtained to increase the possibility of isolating causative organisms 3

Third-generation cephalosporins are the first-line treatment in settings where multidrug-resistant organisms (MDROs) are not prevalent 3, 1
Recommended regimen: Cefotaxime 2g IV every 8 hours for 5 days 1
A 5-day treatment course has been shown to be as effective as a 10-day course 3, 1
Intravenous albumin (1.5 g/kg at diagnosis, followed by 1 g/kg on day 3) should be administered alongside antibiotics to significantly reduce the risk of hepatorenal syndrome and mortality 5, 1

For patients who cannot tolerate IV therapy and have no vomiting, shock, grade II (or higher) hepatic encephalopathy, or serum creatinine >3 mg/dL, oral ofloxacin can be considered as effective as parenteral cefotaxime 5
For nosocomial infections or patients with recent hospitalization and critically ill patients, broader spectrum antibiotics such as carbapenems may be necessary due to higher prevalence of MDROs 3, 4

A repeat paracentesis should be performed after 48 hours of treatment to assess response 1
Treatment failure is defined as failure of ascitic neutrophil count to decrease by at least 25% of pre-treatment value or worsening of clinical signs and symptoms 1
If treatment fails, consider resistant bacteria requiring antibiotic change based on culture results or secondary bacterial peritonitis requiring surgical evaluation 2, 1

Secondary bacterial peritonitis (due to surgically treatable intra-abdominal source) should be suspected if:
If secondary peritonitis is suspected, imaging tests such as abdominal CT should be performed 2

Spontaneous infections are typically monobacterial, with gram-negative bacteria (especially E. coli and Klebsiella) accounting for ~60% of infections 3
There has been a shift toward gram-positive and multidrug-resistant organisms, particularly in nosocomial and healthcare-associated infections 3, 4
Regular monitoring of local resistance patterns is essential for guiding empirical therapy 3

Delaying treatment until culture results are available is not advisable as it can worsen outcomes 5
"Clinical diagnosis" without performing paracentesis is inadequate and can lead to inappropriate treatment 5
Failure to administer albumin alongside antibiotics may result in higher mortality rates 5, 1
Not considering local resistance patterns when selecting empirical therapy can lead to treatment failure 3, 4
Not differentiating between spontaneous and secondary bacterial peritonitis can lead to inappropriate management 2