MADRID – Outpatient oral antibiotics were more successful than outpatient parenteral antibiotic therapy at treating children with community-acquired pneumonia complicated by empyema, in a study presented at the annual meeting of the European Society for Paediatric Infectious Diseases.
Thirty-five percent of the patients were culture positive, a typically low rate that makes treatment of this disease particularly challenging, Lauren Kushner, a medical student at the University of California, Irvine, and one of the study’s authors, said at the meeting.
The treatment success rates, which were defined as improvement with no change in treatment, were 93% for the patients taking oral antibiotics and 58% in the patients on outpatient parenteral antibiotic therapy.
This retrospective observational study included 149 patients under age 18 years hospitalized for community-acquired pneumonia complicated by empyema, at Children’s Hospital of Orange County, Calif. Only 12 of the patients were treated with parenteral antibiotic therapy and none of the study participants had comorbid chronic medical conditions. As in other studies, Streptococcus pneumoniae was the most commonly identified pathogen.
Laboratory markers of inflammation are useful in guiding oral antibiotic therapy for children with CAP complicated by empyema, reported Ms. Kushner.
“A rapid drop in C-reactive protein [CRP] in combination with a decrease in white blood cell count [WBC] can be used acutely in the hospitalization phase to tell you the patient is improving on the selected antibiotic and also to help dictate when the patient might be able to go home, whereas improvement in the erythrocyte sedimentation rate [ESR] does not happen until much later in the course of treatment but can be used to tell you when a patient has been adequately treated,” said Ms. Kushner.
One hundred thirty-seven patients were discharged on oral antibiotic therapy, as is strongly recommended in Infectious Diseases Society of America guidelines for postdischarge treatment of complicated pneumonia, even though there are no randomized clinical trials demonstrating it to be superior or even noninferior to outpatient parenteral antibiotics. An aminopenicillin was the most frequently prescribed type of oral antibiotic, while ceftriaxone was the top choice for outpatient parenteral therapy.
The average total duration of antibiotic therapy, inpatient plus outpatient, was similar in the two groups: 30.4 days in the oral antibiotic group and 33.2 days in children on outpatient IV therapy.
The transition to oral therapy occurred a median of 6 days after admission. At that point, CRP levels had dropped sharply by a mean of 204 mg/L from a baseline of more than 250 mg/L at admission. In the same time frame, mean WBC dropped by 6,400 cells/mcL from close to 20,000/mcL at admission. Thus, sharp declines in these two inflammatory markers while a patient is still in the hospital provide reassurance that antibiotic therapy is on the right track. Their rate of decline slowed considerably after the switch to oral therapy: for example, mean CRP decreased by only another 44 mg/L from switch to discharge, and by a further 19 mg/L from discharge to end of treatment.
In contrast, the mean ESR remained elevated at a level approaching 100 mm/hour with little fluctuation from admission through discharge. Weekly monitoring of ESR post discharge showed that this inflammatory marker improved only late in the course of oral therapy. A drop to less than 30 mm/hour indicates the infection has resolved, Ms. Kushner said.
She noted that in contrast to her study findings, a recent multicenter, 2,123-patient study by the Pediatric Research in Inpatient Settings Network found that treatment failure rates didn’t differ significantly between the two treatment strategies (Pediatrics. 2016 Dec;138. pii: e20161692). Similarly, a retrospective study of 391 children with empyema admitted to Primary Children’s Hospital in Salt Lake City found closely similar rates of treatment failure and other complications regardless of whether the patients were placed on outpatient oral or parenteral antibiotic therapy (Hosp Pediatr. 2015 Dec;5:605-12).
Ms. Kushner reported having no financial conflicts of interest regarding the study.