Transition to oral antibiotic therapy for pyelonephritis in children under 60 days of age: An observational retrospective cohort study.

OBJECTIVES: To describe the use of antibiotics and assess if an early transition from intravenous to oral antibiotic therapy is generally safe in infants less than 60 days of age with a diagnosis of pyelonephritis. METHODS: This retrospective observational cohort study included hospitalized infants less than 60 days with a diagnosis of pyelonephritis based on fever or systemic symptoms and a positive urine culture between January 1, 2015 and July 30, 2017 at a Canadian paediatric tertiary care centre. RESULTS: A total of 108 infants were included. Forty-eight of them were under 1 month of age. The median intravenous (IV) antibiotic therapy duration was 3.5 days, with a longer duration of 4 days in infants less than 1 month of age. The total antibiotic therapy was almost equally divided between a shorter (10 days) and longer (14 days) duration. The recurrence of pyelonephritis within the 2 months following the initial urinary infection was 9 % in the group with IV antibiotic therapy duration of <4 days, compared to 11% in the group treated ≥4 days IV (P-value 0.75). There was a recurrence of pyelonephritis of 10.2% in the group treated for 10 days, compared to 11.5% of recurrence in the group treated for 14 days (P-value 1.0). CONCLUSIONS: Our study provides limited retrospective data regarding the management of pyelonephritis in infants less than 60 days of age. Prospective research is needed to confirm those findings.

New Reference Values for Cardiopulmonary Exercise Testing in Children.

INTRODUCTION: Cardiopulmonary exercise testing is an essential tool to assess cardiorespiratory fitness (CRF) in children. There is a paucity of adequate pediatric reference values that are independent of body size and pubertal stage. The purpose of this study is to provide Z score equations for several maximal and submaximal CRF parameters derived from a prospectively recruited sample of healthy children. METHODS: In this cross-sectional multicenter study, we prospectively recruited 228 healthy children 12 to 17 yr old in local schools. We performed a symptom-limited cardiopulmonary exercise testing progressive ramp protocol on an electronically braked cycle ergometer. Eighteen CRF parameters were analyzed. We tested several regression models to obtain prediction curves that minimized residual association with age, body size, and pubertal stage. Both the predicted mean and the predicted SD were modeled to account for heteroscedasticity. RESULTS: We identified nonlinear association of CRF parameters with body size and significant heteroscedasticity. To normalize CRF parameters, the use of a single body size variable was not sufficient. We therefore used multivariable models with various combination of height, corrected body mass, and age. Final prediction models yielded adjusted CRF parameters that were independent of age, sex, body mass, height, body mass index, and Tanner stages. CONCLUSIONS: We present Z score equations for several CRF parameters derived from a healthy pediatric population. These reference values provide updated predicted means and range of normality that are independent of sex and body size. Further testing is needed to assess if these reference values increase sensitivity and specificity to identify abnormal cardiorespiratory response in children with chronic diseases.