Objectives: To analyze risk factors for serious bacterial illness (SBI) in children less than 2 years of age admitted with fever without source.
Population: Children under 2 years admitted at the Pediatric Service of Sanatorio Mater Dei from May 2004 to December 2005.
Design: Observational, prospective and longitudinal study.
Independent variables: age, gender, siblings, household viral infections, day care attendance, vaccination, season, laboratory data, Rochester criteria, YIOS scale, antibacterial treatment, length of hospitalization, and final diagnosis. A multiple logistic regression stepwise model was used.
Results: 70 out of 201 patients developed SBI, 56 were under 3 months of age. Predominant diagnosis were: urinary tract infection (n: 47), meningitis (n: 11) and bacteremia (n: 9). Predictive factors: white-cells count > 15.000/mm3 (coef 1.05, OR = 2.17, 95% CI 1.13-4.15) and household viral contact (coef-0.79, OR 0.42, CI 0.23-0.77).
Conclusions: Risk factor for SBI was leucocytes count >15.000/mm3. Household viral contact proved being a protective factor.