Antipseudomonal Antibiotics and CTX/MTZ Similarly Effective for Perforated Appendicitis

Children with perforated appendicitis had similar outcomes whether treated with antipseudomonal antibiotics or ceftriaxone plus metronidazole (CTX/MTZ), found authors of a retrospective cohort study reported at IDWeek.

NEW ORLEANS, LA—Children with perforated appendicitis had similar outcomes whether treated with antipseudomonal antibiotics or ceftriaxone plus metronidazole (CTX/MTZ), according to findings from a single-institution retrospective cohort study presented at IDWeek 2016. Average length of hospitalization did not differ between patients treated with the two regimens.

“In a multivariable logistic regression model adjusting for measured confounders, the odds of treatment failure with antipseudomonal antibiotics was 1.38 (95% CI: 0.65–2.93) compared to treatment with CTX/MTZ,” reported lead study author Rana F. Hamdy, MD, MPH, of the Children’s National Health System, Washington, DC.

“Appendicitis is the most common pediatric surgical emergency and one of the most common indications for antibiotic use in hospitalized children,” Dr. Hamdy noted. However, “antibiotic choice for appendicitis varies widely across children’s hospitals, and the optimal antibiotic regimen for perforated appendicitis remains unclear.”

The research team therefore identified children who had been hospitalized between January 2011 and March 2015 and undergone surgery, using ICD-9 codes confirmed by chart review. (Excluded from analysis were those admitted for ≥48 hours prior to diagnosis, had a prior history of appendicitis, or who were immunocompromised. Also excluded were those who had received inotropic agents or an antibiotic regimen other than CTX/MTZ or an antipseudomonal regimen that included cefepime, piperacillin-tazobactam, ciprofloxacin, imipenem, or meropenem within the first 2 days of diagnosis.)

The primary study outcome was “inpatient treatment failure, defined as development of wound infection or abscess prior to discharge,” Dr Hamdy reported.

Of the 353 children identified, 252 (71%) had received CTX/MTZ and 101 (29%), an antipseudomonal antibiotics (piperacillin-tazobactam or ciprofloxacin). The proportion of children treated with antipseudomonal antibiotics varied from 0 to 100%.

“Antibiotic choice for perforated appendicitis varied widely among providers,” Dr. Hamdy noted, but failure rates did not differ between the two groups of children.

Treatment failure occurred in 13.1% of the children receiving CTX/MTZ, and 15.8% of those receiving antipseudomonal antibiotics. Antibiotic-related complications were observed in 4.4% of children on CTX/MTZ and 5.1% of children on antipseudomonal antibiotics. Neither difference was statistically significant. Average length of stay was 6.4 days and 6.3 days for children on CTX/MTZ and antipseudomonal antibiotics, respectively.