Study: Predicted Activity of Oral Antibiotics for Suspected Peritonitis

Delays in initiating antibacterial therapy for the treatment of peritonitis may lead to increased risk of peritoneal dialysis (PD) failure. Because intraperitoneal (IP) antibiotic treatment is not available after business hours at most dialysis centers, having a protocol in place for oral bridge therapy until a patient can receive IP treatment may decrease hospitalization risk and extend time on therapy. Historically, ciprofloxacin (a fluoroquinolone antibiotic) has been the oral medication given for suspected peritonitis. However, when used systemically, fluoroquinolone antibiotics have been associated with disabling and potentially permanent side effects and in 2016, the FDA issued a safety communication recommending that fluoroquinolone antibiotic use be restricted to patients for whom there are no other treatment options. To inform the development of alternative strategies for oral bridge therapy in the treatment of peritonitis, the Home Dialysis team of DaVita Kidney Care evaluated the predicted susceptibility of the infections observed among PD patients to selected oral antibiotics.

Among the cases of peritonitis in DaVita patients during 2016, the most common causative organisms were coagulase-negative Staphylococcus and gram-negative rods. Based on the observed distribution of causative pathogens, trimethoprim/sulfamethoxazole (TMP/SMX) was predicted to be the most active agent for gram positive infections (74.3% of infections susceptible), followed by cefdinir, cefazolin, and ciprofloxacin (62.7%, 48.5%, and 42.4% of infections susceptible, respectively). Among gram-negative infections, ciprofloxacin was predicted to be the most active agent (84.3% of infections susceptible), with lower predicted activity for the other agents (50.0% to 69.8% of infections susceptible).

The findings from this study suggest that TMP/SMX and cefdinir would be the most active oral agents for oral bridge therapy in suspected gram-positive infections. In accordance with FDA recommendations, ciprofloxacin should be used for peritonitis oral bridge therapy only in the case of suspected high-risk, gram-negative infections.

For more information, read the research poster (which was presented at ASN), here.