Serious bacterial infections is uncommon in infants with bronchiolitis

Luginbuhl LM, Newman TB, Pantell RH, Finch SA, Wasserman RC. Office-based treatment and outcomes for febrile infants with clinically diagnosed bronchiolitis. Pediatrics 2008;122:947-54 

Questions Among infants with fever seen in the outpatient office setting, how common is serious bacterial illness? How are these patients managed?

Design Prospective cohort study.

Setting Pediatric Research in Office Settings network.

Participants A total of 3066 infants with fever (<3 months of age with temperatures ≥38° C).

Outcomes Frequency of sepsis evaluation, parenteral antibiotic treatment, and serious bacterial illness in infants with and without clinically diagnosed bronchiolitis. Predictors of sepsis evaluation and parenteral antibiotic treatment in infants with bronchiolitis were identified with logistic regression models.

Main Results Practitioners were less likely to perform a complete sepsis evaluation, urine testing, and cerebrospinal fluid culture and to administer parenteral antibiotic treatment for infants with bronchiolitis, compared with those without bronchiolitis. Significant predictors of sepsis evaluation in infants with bronchiolitis included younger age, higher maximal temperature, and respiratory syncytial virus testing. Predictors of parenteral antibiotic use included initial ill appearance, age of <30 days, higher maximal temperature, and general signs of infant distress. Among infants with bronchiolitis (n = 218), none had serious bacterial illness, and those with respiratory distress signs were less likely to receive parenteral antibiotic treatment. Diagnoses among 2848 infants with fever without bronchiolitis included bacterial meningitis (n = 14), bacteremia (n = 49), and urinary tract infection (n = 167).

Conclusions In office settings, serious bacterial illness in young infants with fever and clinically diagnosed bronchiolitis is uncommon. Limited testing for bacterial infections seems to be an appropriate management strategy.

Commentary Serious bacterial infections among infants hospitalized with bronchiolitis are uncommon. This study, not surprisingly, shows that serious bacterial infections among infants treated for bronchiolitis in primary care settings is at least as unlikely. Notably, however, the infants with bronchiolitis were more ill-appearing than those without bronchiolitis; yet they were only half as likely to be evaluated for sepsis and receive parenteral antibiotics, suggesting that the clinical diagnosis of a viral infection primarily predicts the physician's management and comfort level. In contrast, infants hospitalized with bronchiolitis infection still frequently receive antibiotics and other therapies not recommended for bronchiolitis,1, 2 despite laboratory confirmation of respiratory syncytial virus. This difference in the management of bronchiolitis in the hospital and office setting may have important implications clinically and economically. The practitioner's close relationship to the family and readily available follow-up may be major factors in diminishing unnecessary therapies and laboratory analyses. The economic importance of these potential cost savings in office-based care of bronchiolitis is emphasized by the significantly greater proportion of the bronchiolitis burden that results from office visits compared with hospitalization or emergency department visits, an estimated 24- to 8-fold, respectively.3 However, the infants with bronchiolitis in this study compared with those without bronchiolitis were significantly more likely to undergo chest radiography, oxygen saturation measurements, respiratory syncytial virus testing, to become hospitalized, and to require more follow-up visits. Thus do infants diagnosed with bronchiolitis in office settings actually have fewer total therapies, diagnostic procedures, and costs than infants with fever without bronchiolitis? That question remains to be answered.