Prevalence of Bacteremia in Pediatric Patients With CAP
Prevalence of Bacteremia in Pediatric Patients With CAP
There were 658 children with a provider diagnosis of CAP and blood culture information available. The median patient age was 3.1 years (IQR: 1.3–6.7). Intensive care unit admission, indicating severe disease, occurred in 11.9% (78/658) of patients; 47.4% (37/78) required endotracheal intubation and 33.3% (26/78) received vasopressor support. Blood cultures were performed in 369 (56.1%) of 658 children. Bacteremia was present in 26 (3.9%) of 658 children hospitalized with CAP overall and in 26 (7.1%) of 369 of those who had a blood culture obtained (Table, Supplemental Digital Content 1, http://links.lww.com/INF/B562). Differences in age, gender, race, insurance type, duration of illness, outpatient visits and antibiotic therapy before admission were not significant between patients with bacteremia compared with those with either a negative blood culture or no blood culture (Table, Supplemental Digital Content 2, http://links.lww.com/INF/B563). However, children with either complicated pneumonia or pneumonia-associated metastatic complications were significantly more likely to have bacteremia than those with uncomplicated pneumonia. In addition, patients with bacteremia compared with those without blood culture were more likely to be admitted to the intensive care unit (Table, Supplemental Digital Content 2, http://links.lww.com/INF/B563).
Patients with bacteremia had longer fever duration before admission and supplemental oxygen requirement during hospitalization than those without a blood culture obtained. This was not true when compared with those with a negative blood culture (Table, Supplemental Digital Content 2, http://links.lww.com/INF/B563). Median length of stay was longer in children with bacteremia than those with negative blood cultures and those without blood cultures.
Most children underwent laboratory evaluation, the most common of which was a white blood cell count in 480 (73.0%) children. C-reactive protein was obtained in 153 (23.3%) patients, and an erythrocyte sedimentation rate was obtained in 54 (8.2%) patients. Patients with bacteremia had higher median C-reactive protein values than those who had a negative culture or no blood culture. However, no differences were found in median white blood cell counts or erythrocyte sedimentation rate values across groups (Table, Supplemental Digital Content 2, http://links.lww.com/INF/B563).
Differences across age groups for findings on initial chest radiograph were not significant. Three-fourths of all children with metastatic complications had bacteremia compared with 6–10% of children without metastatic complications (Table 1). In addition, bacteremia was more common among children who underwent a pleural drainage procedure than those who did not have a pleural drainage procedure (Table 1).
The most common pathogen was S. pneumoniae, which was identified in 19 (73.1%) of 26 children with bacteremia and in 19 (5.1%) of 369 of patients with CAP who had a blood culture obtained. The remaining pathogens causing bacteremia included H. influenzae (n = 1) and Staphylococcus aureus (n = 6); 3 of the 6Staphylococcus aureus isolates were methicillin-resistant. Penicillin susceptibilities were available for 16 (84.2%) pneumococcal isolates; 75% were penicillin susceptible, 6.3% were intermediate and 18.8% were resistant. Two of the 3 isolates that were penicillin resistant were also resistant to third-generation cephalosporins. All isolates tested were susceptible to levofloxacin, but 2 (18%) of 11 isolates were resistant to meropenem. All methicillin-resistant Staphylococcus aureus isolates were susceptible to clindamycin and vancomycin. The H. influenzaeisolate did not exhibit [beta]-lactamase production.
Eleven (9.8%) of 112 pleural fluid cultures were positive. Pleural fluid isolates included S. pneumoniae (n = 8) and Staphylococcus aureus (n = 3); 2 of theStaphylococcus aureus pleural fluid isolates were methicillin resistant. Thirty-three patients had both blood and pleural fluid cultures performed; 20 (60.6%) had negative results for both pleural fluid and blood culture, whereas 6 (18.2%) patients had positive pleural fluid and negative blood cultures. Of the remaining patients, both blood and pleural fluid were positive in 3 (9.1%) and blood culture alone revealed a pathogen in 4 (12.1%) of patients.
Hospital Variation
The proportion of children with blood cultures obtained ranged from 42.5% to 65.0% of CAP admissions across hospitals (Table 2). In addition, pneumonia sequelae and pleural drainage procedures were low and similar across institutions. Discharge antibiotic therapy varied across the 4 hospitals with a mean of 55.8% (range: 27.6–77.8%) receiving a broad spectrum agent. In addition, while most patients received enteral antibiotics at discharge, there was a significant variation across hospitals ranging from 82.0% to 96.7%; the remaining patients received parenteral therapy in the home setting (Table 2).
Overall, 591 patients (89.8%) were discharged with enteral therapy, 22 (3.3%) received parenteral therapy and 45 (6.8%) were discharged without antibiotic therapy. The median length of stay was longer for children discharged without antibiotic therapy (110 hours [IQR: 45–290]) compared with patients discharged with antibiotic therapy (51 hours [IQR: 38–87]; P < 0.001). In addition, most patients with bacteremia (96%) were discharged home with antibiotic therapy. Patients with bacteremia or any pneumonia-related sequelae were more likely to be discharged home with parenteral therapy than those with uncomplicated pneumonia (29.5% versus 1.5%, P < 0.001). Furthermore, patients with bacteremia were more likely to be discharged with a broad spectrum agent either parenterally or orally administered (80.0% versus 57.7%, P = 0.026).
Overall, 10 (38.5%) of 26 patients with bacteremia had their therapy broadened, 7 (27%) of 26 were narrowed and 9 (34.6%) of 26 had no change based on culture results (Table, Supplemental Digital Content 1,http://links.lww.com/INF/B562). Of the patients for whom susceptibilities were available, 6 (26.1%) of 23 received a narrower spectrum of antibiotic therapy at discharge, although the narrowest effective antibiotic was not used in 1 case (ie, case 12 in which the patient could have been discharged with amoxicillin instead of a third-generation cephalosporin for a penicillin susceptible pneumococcus; Table, Supplemental Digital Content 1, http://links.lww.com/INF/B562). Blood culture–directed changes in therapy occurred in 37.5% (all broadened) of patients who were determined to have a contaminated culture (n = 8). Of the 6 patients with contaminated culture results who received an antibiotic at discharge, only one-third received narrowest therapy possible.
Results
Clinical, Laboratory and Radiographic Features
There were 658 children with a provider diagnosis of CAP and blood culture information available. The median patient age was 3.1 years (IQR: 1.3–6.7). Intensive care unit admission, indicating severe disease, occurred in 11.9% (78/658) of patients; 47.4% (37/78) required endotracheal intubation and 33.3% (26/78) received vasopressor support. Blood cultures were performed in 369 (56.1%) of 658 children. Bacteremia was present in 26 (3.9%) of 658 children hospitalized with CAP overall and in 26 (7.1%) of 369 of those who had a blood culture obtained (Table, Supplemental Digital Content 1, http://links.lww.com/INF/B562). Differences in age, gender, race, insurance type, duration of illness, outpatient visits and antibiotic therapy before admission were not significant between patients with bacteremia compared with those with either a negative blood culture or no blood culture (Table, Supplemental Digital Content 2, http://links.lww.com/INF/B563). However, children with either complicated pneumonia or pneumonia-associated metastatic complications were significantly more likely to have bacteremia than those with uncomplicated pneumonia. In addition, patients with bacteremia compared with those without blood culture were more likely to be admitted to the intensive care unit (Table, Supplemental Digital Content 2, http://links.lww.com/INF/B563).
Patients with bacteremia had longer fever duration before admission and supplemental oxygen requirement during hospitalization than those without a blood culture obtained. This was not true when compared with those with a negative blood culture (Table, Supplemental Digital Content 2, http://links.lww.com/INF/B563). Median length of stay was longer in children with bacteremia than those with negative blood cultures and those without blood cultures.
Most children underwent laboratory evaluation, the most common of which was a white blood cell count in 480 (73.0%) children. C-reactive protein was obtained in 153 (23.3%) patients, and an erythrocyte sedimentation rate was obtained in 54 (8.2%) patients. Patients with bacteremia had higher median C-reactive protein values than those who had a negative culture or no blood culture. However, no differences were found in median white blood cell counts or erythrocyte sedimentation rate values across groups (Table, Supplemental Digital Content 2, http://links.lww.com/INF/B563).
Differences across age groups for findings on initial chest radiograph were not significant. Three-fourths of all children with metastatic complications had bacteremia compared with 6–10% of children without metastatic complications (Table 1). In addition, bacteremia was more common among children who underwent a pleural drainage procedure than those who did not have a pleural drainage procedure (Table 1).
Microbiologic Features
The most common pathogen was S. pneumoniae, which was identified in 19 (73.1%) of 26 children with bacteremia and in 19 (5.1%) of 369 of patients with CAP who had a blood culture obtained. The remaining pathogens causing bacteremia included H. influenzae (n = 1) and Staphylococcus aureus (n = 6); 3 of the 6Staphylococcus aureus isolates were methicillin-resistant. Penicillin susceptibilities were available for 16 (84.2%) pneumococcal isolates; 75% were penicillin susceptible, 6.3% were intermediate and 18.8% were resistant. Two of the 3 isolates that were penicillin resistant were also resistant to third-generation cephalosporins. All isolates tested were susceptible to levofloxacin, but 2 (18%) of 11 isolates were resistant to meropenem. All methicillin-resistant Staphylococcus aureus isolates were susceptible to clindamycin and vancomycin. The H. influenzaeisolate did not exhibit [beta]-lactamase production.
Eleven (9.8%) of 112 pleural fluid cultures were positive. Pleural fluid isolates included S. pneumoniae (n = 8) and Staphylococcus aureus (n = 3); 2 of theStaphylococcus aureus pleural fluid isolates were methicillin resistant. Thirty-three patients had both blood and pleural fluid cultures performed; 20 (60.6%) had negative results for both pleural fluid and blood culture, whereas 6 (18.2%) patients had positive pleural fluid and negative blood cultures. Of the remaining patients, both blood and pleural fluid were positive in 3 (9.1%) and blood culture alone revealed a pathogen in 4 (12.1%) of patients.
Hospital Variation
The proportion of children with blood cultures obtained ranged from 42.5% to 65.0% of CAP admissions across hospitals (Table 2). In addition, pneumonia sequelae and pleural drainage procedures were low and similar across institutions. Discharge antibiotic therapy varied across the 4 hospitals with a mean of 55.8% (range: 27.6–77.8%) receiving a broad spectrum agent. In addition, while most patients received enteral antibiotics at discharge, there was a significant variation across hospitals ranging from 82.0% to 96.7%; the remaining patients received parenteral therapy in the home setting (Table 2).
Discharge Antibiotic Therapy
Overall, 591 patients (89.8%) were discharged with enteral therapy, 22 (3.3%) received parenteral therapy and 45 (6.8%) were discharged without antibiotic therapy. The median length of stay was longer for children discharged without antibiotic therapy (110 hours [IQR: 45–290]) compared with patients discharged with antibiotic therapy (51 hours [IQR: 38–87]; P < 0.001). In addition, most patients with bacteremia (96%) were discharged home with antibiotic therapy. Patients with bacteremia or any pneumonia-related sequelae were more likely to be discharged home with parenteral therapy than those with uncomplicated pneumonia (29.5% versus 1.5%, P < 0.001). Furthermore, patients with bacteremia were more likely to be discharged with a broad spectrum agent either parenterally or orally administered (80.0% versus 57.7%, P = 0.026).
Overall, 10 (38.5%) of 26 patients with bacteremia had their therapy broadened, 7 (27%) of 26 were narrowed and 9 (34.6%) of 26 had no change based on culture results (Table, Supplemental Digital Content 1,http://links.lww.com/INF/B562). Of the patients for whom susceptibilities were available, 6 (26.1%) of 23 received a narrower spectrum of antibiotic therapy at discharge, although the narrowest effective antibiotic was not used in 1 case (ie, case 12 in which the patient could have been discharged with amoxicillin instead of a third-generation cephalosporin for a penicillin susceptible pneumococcus; Table, Supplemental Digital Content 1, http://links.lww.com/INF/B562). Blood culture–directed changes in therapy occurred in 37.5% (all broadened) of patients who were determined to have a contaminated culture (n = 8). Of the 6 patients with contaminated culture results who received an antibiotic at discharge, only one-third received narrowest therapy possible.