Treatment failure with out-patient therapy of community-acquired pneumonia

Hershberger, E.; Lajin, M.; Chirilla, R.; Zervos, M. J.

We conducted a retrospective study to evaluate predictors of outpatient antimicrobial treatment failure in community-acquired pneumonia. From July 2000 to April 2001 hospitalized pts with a diagnosis of CAP were identified. Charts of 72 pts who had received antibiotics prior to admission were evaluated. Data was collected on outpatient antibiotic therapy, comorbidity, sign/symptoms of pneumonia, Pneumonia Severity Index (PSI), and pathogen susceptibility. Both genders were represented equally and age groups were: 25%>50 yrs, 26% 50-70 yrs, and 49%>70 yrs. 58% of the pts were smokers. COPD/asthma was the most common comorbid condition (50%) followed by malignancy (28%) and diabetes (24%). The most frequent symptoms were cough (93%), dyspnea (69%), sputum production (67%), fever (60%), chills (30%), and chest pain (30%), and 50% had leukocytosis. S. pneumoniae was isolated from 19% of the pts. Based on PSI scoring system 50% of the pts were in the low (PSI<90), 37% in moderate (PSI 90-130) and 13% in high (PSI<130) risk groups. The most commonly used class of antibiotic prior to admission was macrolide 44% (azithromycin n=20, clarithromycin n=8, erythromycin n=5) followed by quinolone 23%, penicillin 13%, and cephalosporin 9%. The length of therapy varied from 1-14 days with 81% receiving antibiotic for >3 days. Twelve percent of the pts had no comorbid conditions while 78% had one or more coexisting illnesses. Among the individuals without co-morbid illness with documented S. pneumoniae, 67% were resistant to the antibiotic selected for therapy. 35% of macrolide (azithromycin n=3, clarithromycin n=l, and erythromycin n=2) and 50% of PCN failure pts had susceptible pathogens, suggesting other reasons for treatment failure. In conclusion PSI scoring was not a good predictor of admission making decision. Age>70, COPD/asthma, underlying malignancy, and diabetes were risk factors for outpatient treatment failure of CAP.